Mekjell Meland
Research Professor
(+47) 906 28 538
mekjell.meland@nibio.no
Place
Ullensvang
Visiting address
NIBIO Ullensvang, NO-5781 Lofthus
Abstract
No abstract has been registered
Authors
Mekjell MelandAbstract
No abstract has been registered
Authors
Maja Natić Dragana Dabić Zagorac Mihajlo Jakanovski Anita Smailagić Slavica Čolić Mekjell Meland Milica Fotirić AkšićAbstract
No abstract has been registered
Abstract
No abstract has been registered
Abstract
No abstract has been registered
Abstract
No abstract has been registered
Abstract
No abstract has been registered
Abstract
The commercial apple production in Norway is limited to the small regions along the fjord areas in the southwest part of the country and around lakes or near the sea in the southeast part with favorable climate. Due to the rapid rate of climate change over the recent decades, it is expected that suitable heat conditions for apple growing will expand to the areas that previously were too cold. This study analyses the heat suitability of past, present and future climate for six commercial apple varieties in Norway (Discovery, Gravenstein, Summerred, Aroma, Rubinstep, and Elstar). The methodology for identifying favorable heat conditions is developed using meteorological and phenological observations from the Ullensvang orchards and applied on a high-resolution gridded datasets of temperature observations and climate projections. The assessment indicates that with increasing temperatures, heat conditions suitable for cultivation all six apple varieties are expanding. The surfaces with favorable heat conditions for less heat-demanding varieties increased threefold over the last 60 years. In the period 2011-2020, heat suitable climate for cultivating at least one of the considered apple varieties is found at 15% of the analyzed territory, while 2.5% was suitable for growing all six varieties. In the future, the favorable areas will advance from south and southeast northwards and inland in the eastern region, along the west and northwestern coastline towards higher latitudes, and along continental parts of fjords. The fastest expansion of heat suitable conditions is expected for less heat-demanding varieties. The findings of this study show an increasing potential for apple production in Norway that are relevant for strategical planning of climate change adaptation measures within the sector. Weather related risks, such as the risk from damaging low temperatures, drought and extreme precipitation were not considered.
Abstract
No abstract has been registered
Abstract
No abstract has been registered
Abstract
No abstract has been registered
Authors
Milica Fotirić Akšić Živoslav Tešić Milica Kalaba Ivanka Ćirić Lato Pezo Biljana Lončar Uroš Gašić Biljana Dojčinović Tomislav Tosti Mekjell MelandAbstract
The aim of this study was to find the chemical parameters for the differentiation of plum cultivars grown along the fjord areas of Western Norway and Eastern Norway, having specific agroclimatic conditions. Chemical analysis of the fruits confirmed the contents of 13 quantified elements, 22 sugar compounds, 11 organic acids, 19 phenolic compounds, and antioxidant activity in 68 plum cultivars. Dominated contents were noted for nitrogen (with the maximum mean value of 3.11%), potassium (8055.80 mg/kg), and phosphorous (7878.88 mg/kg). Averagely, the highest level of sugars was determined for glucose (244.46 g/kg), fructose (197.92 g/kg), sucrose (208.25 g/kg), and sorbitol (98.02 g/kg), organic acids for malic acid (24.06 g/kg), and for polyphenol compounds were 5-O-caffeoylquinic acid (66.31 mg/kg), and rutin (58.06 mg/kg). Applied principal component analysis has been useful for distinguishing the plum cultivars from three areas in Norway where copper, iron, potassium, magnesium, manganese, and sodium; sucrose, ribose, maltose, and raffinose; p-hydroxybenzoic acid, rutin, ferulic acid, kaempferol 7-O-glucoside, p-coumaric acid, and 5-Ocaffeoylquinic acid were the most influential. In regard to human health and future breeding work that will have the aim to produce functional food with high health-related compounds, the plum cultivar ‘Mallard’ should be underlined due to the high level of elements, ‘Valor’ due to high sugar content, ‘Helgøyplomme’ due to content of organic acids, and ‘Diamond’ due to the content of phenolic compounds.
Abstract
The commercial apple production in Norway is limited to the small regions along the fjords in the southwest part of the country and around lakes or near the sea in the southeast with favorable climate. Due to the rapid rate of climate change over the recent decades, it is expected that suitable heat conditions for apple growing will expand to the areas that were previously too cold. This study analyses the heat suitability of future climate (2021–2100) under the RCP8.5 scenario for 6 common apple varieties in Norway: Discovery, Gravenstein, Summerred, Aroma, Rubinstep and Elstar. Previously established heat requirement criteria (based on the temperature threshold for the full blooming and growing degree days sum between the full bloom and harvest) are applied to the temperature outputs of the regional climate models downscaled to 1 km resolution. The assessment indicates that as temperature rises, heat conditions suitable for cultivation of all 6 apple varieties will expand. According to the ensemble median value, areas with the favorable heat conditions for growing at least one of the considered apple varieties will increase 25 times in the period 2021–2040 and 60 times in the period 2041–2060, compared to the referent period 1971–2000. At the same time, areas suitable for all 6 apple varieties will increase 3 times in the first, and 3.8 times in the latter period. The favorable areas will advance from south and southeast northwards and inland in the eastern region, along the west and northwestern coastline towards higher latitudes, and along continental parts of fjords. The fastest expansion of heat suitable conditions is expected for Discovery and Gravenstein. The findings of this study are relevant for zoning apple production future potential and for strategical planning of climate change adaptation measures within the sector. Weather-related risks, such as risks from winter low temperatures, spring frost, drought and extreme precipitation were not considered.
Authors
Ana Vuković Vimić Mirjam Vujadinović Mandić Milica Fotirić Akšić Ksenija Vukićević Mekjell MelandAbstract
Agricultural production is already, and obviously, affected by climate change. Adapting to climate change includes reducing future risks to ensure yield quality and quantity and considers seizing any potential opportunities induced by climate change. In higher latitude areas, such as Norway, cold climate limits the cultivation of fruits. An increase in temperature offers more favorable conditions for fruit production. In this study, using available phenological observations (full blooming) and harvest dates, and meteorological data from the experimental orchard of NIBIO Ullensvang, the minimum heat requirements for growing different apple varieties are determined. Those criteria are used for zoning of the areas with heat favorable conditions for apple growing. Data on six varieties were used, with lower and higher requirements for heat for fruit development (Discovery, Gravenstein, Summerred, Aroma, Rubinstep, and Elstar). High resolution daily temperature data were generated and used for zoning of the areas with heat favorable conditions for apple growing within the selected domain, which includes Western Norway, Southern Norway, Eastern Norway, and the western part of Trøndelag, Mid-Norway. Dynamics of the change in such surfaces was assessed for the period of 1961–2020. The total surface with favorable heat conditions for growing the varieties with lesser requirement for heat increased three times during this period. The growing of more heat-demanding varieties increased from near zero to about 2.5% of the studied land surface. In the period of 2011–2020, surface area with favorable heat conditions for apple growing was almost 27,000 km2, and a surface area of about 4600 km2 can sustain growing of more heat-demanding varieties. The presented results show the increasing potential of the climate of Norway for apple cultivation and highlight the importance of implementation of fruit production planned according to climate change trends, including the assessment of potential risks from climate hazards. However, the methodology for determining heat requirements can be improved by using phenological ripening dates if available, rather than harvest dates which are impacted by human decision. Zoning of areas with the potential of sustainable apple growing requires the use of future climate change assessments and information on land-related features.
Authors
Fuad Gasi Naris Pojskić Belma Kalamujić Stroil Oddmund Frøynes Milica Fotirić Akšić Mekjell MelandAbstract
In order to determine the pollinizer success rates between twelve apple cultivars in 2021 and 2022, 671 apple embryos were collected from 19 different orchards in Ullensvang (southwestern Norway) and Svelvik (southeastern Norway). Genomic DNA was extracted from the collected embryos and, afterward, a genetic characterization with 15 polymorphic microsatellite markers was conducted. An identical set of markers was also used on all twelve mother cultivars, as well as on six crabapple pollinizers, which were found in the investigated orchards. The obtained molecular data enabled paternity analyses to be performed with the objective of assigning a male parent to each embryo. The paternity analyses identified pollen donors for all, except for 3% of the embryos. In most cases, it was possible to identify the most successful pollinizers for each cultivar, with ‘Aroma’ and ‘Discovery’ being the most efficient pollen donors overall. Tree abundance seems to be a major factor in pollinizer success, while semi-cross-compatible characteristics represent a hindrance. Only 7% of the analyzed embryos were determined to have been fertilized by pollinizers outside the orchard, confirming the significance of pollinizer proximity for efficient pollination.
Abstract
The present research was undertaken to investigate polyphenolic profiles of peel, pulp and juices made from two standard commercial and five traditional apple cultivars from Bosnia and Herzegovina. The main goal of the study was to monitor the distribution and changes of polyphenolic profiles through different phases of apples’ processing into cloudy and clear juices, with regard to L-ascorbic acid pretreatment. Quantitative determination of phenolic compounds was carried out by using high-performance liquid chromatography with diode-array detection. The obtained results showed that traditional cultivars, namely ‘Paradija’ and ‘Prijedorska zelenika’, displayed significantly higher content of these compounds compared to commercial ones. Flavan 3-ols and flavonol glycosides were mostly found in peels of all cultivars (21.2–44.1 and 5.40–33.3%, respectively), while phenolic acids along with flavan 3-ols were predominant in the pulp (8.20–30.8 and 5.10–13.9%, respectively). Apples’ processing into juices caused decrease (more than 90%) in the content of all polyphenols and the distribution of these compounds from fruits to final products had a negative trend, particularly evident in clear juices. The most drastic loss occurred in the flavonol glycosides and dihydrochalcones content, while chlorogenic acid displayed quite stable distribution from apples to final products due to its good solubility. Apple mash pretreatment with L-ascorbic acid had a positive impact on the preservation and retention of polyphenols.
Abstract
The aim of this study was to investigate the potential of traditional apple cultivars from Bosnia and Herzegovina to improve the aroma of the less aromatic international cultivar “Idared” in the production of spirits. Two flavor improvement approaches were used: joint fermentation of traditional and “Idared” apples and the maceration of traditional apples in raw “Idared” spirits, followed by redistillation. Minor aroma volatile compounds in the obtained spirits were measured by gas chromatography-mass spectroscopy techniques after enrichment via solid-phase microextraction. Overall, 36 minor volatile compounds were found in spirits. The share of detected compounds varied greatly among samples due to the flavoring approach and used cultivars. Flavor improvement during fermentation proved a more efficient approach. Even 10% share of a traditional apple is enough to improve the positive sensory attributes of the spirits. The obtained results encourage the future use of traditional apple cultivars in the production and flavor improvement of fruit spirits.
Abstract
Global warming benefits enrichment of the assortment of cultivated fruit trees. New fruit species, less winter hardy, demanding higher temperatures during their growth and longer vegetation period, could become new commercial crops in Norwegian orchards. Up to now there is a lack of knowledge and experience with new fruit species in Norway. Main goal of the project was to justify the possibilities of introduction of new fruit crops namely table/wine grapes, peaches, apricots, and nectarines. The project implementation was based on literature analysis, questionnaires of growers and scientists, information gathered during the visits to scientific institutions and farmers in Norway, Sweden, Latvia, and Lithuania. According to growers’ experience and research performed in Norway, neighbouring countries and in regions with similar climate, a number of wine grape and apricot cultivars can be successfully grown in Norway. However, table grapes, peach and especially nectarine are more risky crops. After comprehensive analysis of cultivar characteristics and management, recommendations for the introduction of new cultivars were prepared for commercial growing or additional cultivar evaluation trials.
Authors
Tore Krogstad Valentina Zivanovic Aleksandar Simic Milica Fotiric Aksic Vlado Licina Mekjell MelandAbstract
The mineralization of nitrogen in apple orchard soil will increase the soil supply. An incubation study to test the soil potential and the validity of analytical methods was conducted at 3, 8, 15, and 20 °C for up to 128 days on soils from western and south-eastern Norway. Soils with the highest pH showed the highest mineralization. The mineralization increased with increasing temperature and time, but start-up N reduced mineralization. The mineralization cannot be estimated from standard soil chemical parameters because the different C/N ratio indicates organic material of different origin and quality. The increase in NO3-N started very quickly and ranged from 17 to 182% and 12 to 64% after 8 days at 3 °C and 20 °C, respectively. There was no correlation between total N in the soil and the amount of mineralized N. On average, the mineralization increased by 5–7% for a change of 1 °C in the interval from 8 to 15 °C in the soil. The chemical extraction method using heated KCl correlated well with the mineralization data. On average, the chemical method estimated 30 kg N ha−1, which corresponded to 0.48% of total N. Recommendations for N fertilization based on total N in the soil overestimate the contribution of plant-available N in most cases.
Authors
Mekjell MelandAbstract
No abstract has been registered
Authors
Mekjell MelandAbstract
No abstract has been registered
Abstract
No abstract has been registered
Abstract
This report presents results of two plum cultivars and selections trials, performed during 2013-2021 and 2016-2021 at Ullensvang. In total, 19 plum cultivars were evaluated: 4 from the Institute of Horticulture, Čačak, Serbia; 9 cultivars and selections bred by Einar Ruud, Søgne; 3 plum selections from Graminor, Njøs and 1 cultivar from NMBU. Cultivars Opal and Čačanska lepotica served as control. The aim of these reported plum cultivar trials was to investigate recently released plum cultivars and premium selections from Norwegian and Serbian breeding programs from pomological, agronomical, and biochemical point of view, identify the most important quality parameters, and select cultivars with desirable traits for the modern market in Norway. Based on overall fruit quality and tree productivity, selections NPr. 458 and Anne (R21) (Rudiplomme, if a DNA-test reveal that it is the same as the cultivar Anne (R 21)) are selected for fresh consumption and can be recommended for further commercial growing tests. Due to very sweet and good fruit taste, cultivars Boranka and Ellen might be used for jam.
Authors
Mekjell MelandAbstract
No abstract has been registered
Authors
Milica Fotirić Akšić Marina Mačukanović-Jocić Radenko Radošević Nebojša Nedić Uroš Gašić Tomislav Tosti Živoslav Tešić Mekjell MelandAbstract
The topography and morpho-anatomical characteristics of floral nectaries and the chemical analysis of nectar have been studied in seven pear cultivars with different susceptibility to Erwinia amylovora. The susceptible cultivarWilliams, the moderately resistant cultivars Bella di guigno, Poire de Cure and the low susceptible cultivar Alexander Lucas originated from Pyrus communis, while highly resistant cultivars Chojuro and Nijisseiki from P. pyraster and Kieffer as interspecies hybrid P. communis x P. pyraster were included in this experiment and studied for the first time. Large differences in size and structure of the nectaries were observed in these seven pear cultivars. The epidermal cells were with cuticle being more or less striated in Alexander Lucas, Kieffer and Williams. Resistant cultivars had a narrow, elongated cell shape of epidermal cells while those susceptible had an isodiametric. Stomata were mesomorphic in all cultivars except in Poire de Cure and Williams, being slightly xeromorphic since they were situated in deep hollows. Guard cells of the modified stomata were much larger in resistant cultivars. Hypanthium cells were larger in resistant compared to susceptible cultivars. The most abundant sugars were glucose, fructose, sorbitol and sucrose in nectar of all studied pear cultivars. The resistant cultivars (Chojuro, Kieffer and Nijisseiki) had a ~2-fold higher level of sorbitol and galactose, ~2.2-fold higher isomaltose, ~2.7-fold turanose, ~3.35-fold maltose, ~4.4-fold melibiose and ~12.7-fold higher melesitose compared to susceptible cultivars. The sum of quantified phenolic acids varied from 0.049 (Williams) up to 4.074 µg CAE/mL (Kieffer), while flavonoid glycosides levels ranged from 1.224 (Williams) up to 11.686 µg RE/mL (Nijisseiki). In the nectar of the resistant cultivars, rutin, apigetrin, together with patuletin and luteolin glycosides were detected but not in susceptible cultivars, which could be considered as the markers of resistance.
Authors
Asima Akagić Amila Oras Fuad Gaši Mekjell Meland Pakeza Drkenda Senad Memić Nermina Spaho Sanja Oručević Žuljević Igor Jerković Osman Musić Metka HudinaAbstract
Traditional pear cultivars are increasingly in demand by consumers because of their excellent taste, the possibility of use in sustainable food production systems, convenience as raw materials for obtaining products of high nutritional quality, and perceived health benefits. In this study, individual sugars, organic acids, and polyphenols in the fruits of nine traditional and one commercial pear cultivar during two growing seasons were determined by HPLC. A significant influence of cultivars, growing years, and their interaction on the content of analyzed primary and secondary metabolites was determined. The commercial pear cultivar ‘Président Drouard’ and traditional cultivars ‘Dolokrahan’, ‘Budaljača’, and ‘Krakača’ had a lower content of all analyzed sugars. Overall, traditional pear cultivars had higher total polyphenols in the peel and pulp than ‘Président Drouard’, with the exception ‘Takiša’ and ‘Ahmetova’. High polyphenol content detected in ‘Budaljača’, ‘Dolokrahan’, and ‘Krakača’ shows the utilization value of traditional pear germplasm. The obtained data can serve as practical supporting data for the use of traditional pears in the neutraceutical, pharmaceutical, and food industries.
Authors
Milica Fotirić Akšić Dragana Dabić Zagorac Uroš Gašić Tomislav Tosti Maja Natić Mekjell MelandAbstract
The aim of this study was to compare total phenolic content (TPC), radical-scavenging activity (RSA), total anthocyanin content (TAC), sugar and polyphenolic profiles of two apple cultivars (‘Discovery’ and ‘Red Aroma Orelind’) from organic and integrated production systems in climatic conditions of Western Norway. Sixteen sugars and four sugar alcohols and 19 polyphenols were found in the peel, but less polyphenols were detected in the pulp. The peel of both apples and in both production systems had significantly higher TPC and RSA than the pulp. The peel from integrated apples had higher TPC than the peel from organic apples, while organic apples had higher TAC than the integrated. Sucrose and glucose levels were higher in organic apples; fructose was cultivar dependent while minor sugars were higher in integrated fruits. The most abundant polyphenolic compound in the peel of the tested cultivars was quercetin 3-O-galactoside, while chlorogenic acid was most abundant in the pulp. Regarding polyphenols, phloretin, phloridzin, protocatechuic acid, baicalein and naringenin were higher in organic apple, while quercetin 3-O-galactoside, kaempferol 3-O-glucoside, chlorogenic acid and syringic acid was higher in integrated fruits. In conclusion, organic ‘Discovery’ and integrated ‘Red Aroma Orelind’ had higher bioavailability of health related compounds from the peel and the pulp.
Authors
Mekjell Meland T Tosti Biljana Rabrenovic Sandra Segan D Dabic Zagorac M Natic Milica Fotiric-AksicAbstract
No abstract has been registered
Authors
Mekjell Meland T Tosti Biljana Rabrenovic Sandra Segan D Dabic Zagorac M Natic Milica Fotiric-AksicAbstract
No abstract has been registered
Authors
Milica Fotiric-Aksic Kristina Lazarevic U Gasic T Tosti Z Tesic Radoslav Cerovic Mekjell MelandAbstract
No abstract has been registered
Authors
Milica Fotiric-Aksic Kristina Lazarevic U Gasic T Tosti Z Tesic Radoslav Cerovic Mekjell MelandAbstract
No abstract has been registered
Authors
Milica Fotirić Akšić Milica Nešović Ivanka Ćirić Živoslav Tešić Lato Pezo Tomislav Tosti Uroš Gašić Biljana Dojčinović Biljana Lončar Mekjell MelandAbstract
Raspberries are considered valuable fruits due to their high levels of nutrients and phytochemicals, which have many beneficial effects on humans. As many external factors affect the composition of these fruits (the type of cultivation, soil characteristics, ripeness, storage time and post-harvest technologies, cultivar/genotype, and climatic conditions), the goal of this study was to analyze different raspberry cultivars grown in Norway. Considering that Norway is a country with specific climatic conditions, as well as has a limited period of fruit vegetation, another important goal of this study was also to compare raspberries from different Norwegian areas, as well as different grown cultivars. Modern analytical techniques, such as high-performance anion-exchange liquid chromatography with pulsed amperometric detection (HPEAC-PAD), ultra-high-performance liquid chromatography with diode array detector coupled to triple quadrupole mass spectrometry (UHPLC-DAD MS/MS), and inductively coupled plasma–optical emission spectrometry (ICP-OES), provided a detailed examination of the raspberry extract samples. Based on their high levels of minerals (especially N, P, and K), organic acids (predominantly citric and malic acids), sugars (glucose, fructose, sucrose, and galactose), and polyphenols (ellagic acid, syringic acid, quercetin, and rutin), Norwegian raspberries could be considered fruits with increased health-beneficial compounds. The chemical composition of the studied cultivars depended on the locality of growth.
Authors
Mekjell MelandAbstract
No abstract has been registered
Authors
Boban Djordjević Dejan Djurović Gordan Zec Dragana Dabić Zagorac Maja Natić Mekjell Meland Milica Fotirić AkšićAbstract
The aim of this study was to examine the influence of shoot age on the biological and chemical properties of 13 black currant cultivars with different origins and ripening times. Phenological observations together with examined pomological and chemical characteristics were studied in two consecutive years at the experimental field near Belgrade, Serbia. The total content of phenols was estimated spectrophotometrically by the Folin-Ciocalteu method, while quantitative analysis of anthocyanin and flavonols aglycones was performed using a high-performance liquid chromatographic (HPLC) method. Principal component analysis was performed to establish differences in biological and chemical properties of black currants. Three-year-old shoots had an earlier start of all examined phenological stages, better generative potential, higher yields, while clusters and berries from 2-year-old shoots had significantly higher values for physical properties, total phenols, anthocyanin and flavanols aglycones and antiradical capacity. Late ripening cultivars had higher contents of all chemical compounds. The berries on 2-year-old shoots had total phenolics that ranged between 123.0 (‘Titania’) and 298.3 mg/100 g fresh weight (FW) (‘Ometa’), while total anthocyanins ranged between 398.5 (’Ojebyn’) and 1160.8 mg/kg FW (’Ometa’). According to the obtained results, cultivars ‘Ometa’, ‘Ben Lomond’, ‘Tsema’ and ‘Malling Juel’ can be recommended as the most promising for growing in the continental climate because they stood out with higher generative potential and yield, physical traits of cluster and berry, higher level of primary and secondary metabolites and DPPH activity in their berries.
Authors
Darius Kviklys Vytautas Abukauskas Mekjell Meland Walter Guerra I. Höller N. Dallabetta T. Pantezzi J. Carbo J. Lordan A. Karlström F. Fernandez M. Brüggenwirth L. Laňar M. Mészáros T. Rühmer S. Perren S. Cia S. Codarin V. Mathieu F. Bernard P. Bielicki L. Manfrini L. Corelli Grappadelli A. Gomand Jef VercammenAbstract
In 2017, two multi-location apple rootstock trials were established at 16 sites in 12 European countries. The evaluations are performed by members of the EUFRIN (European Fruit Research Institute Network) Apple & Pear Variety & Rootstock Testing Working Group. Two separate trials were arranged, grouping rootstocks into dwarf and semi-dwarf rootstocks according to the expected vigour; ‘Galaval’ was used as scion cultivar. The trial of dwarf rootstocks includes ‘G.11’ and ‘G.41’ (US), ‘EM_02’, ‘EM_03’, ‘EM_04’, ‘EM_05’ and ‘EM_06’ (UK), ‘62-396-B10®‘ (Russia), ‘P 67’ (Poland), ‘PFR4’ and ‘PFR5’ (New Zealand) and ‘Cepiland-Pajam®2’ as control. The trial of semi-dwarf rootstocks includes ‘G.202’ and ‘G.935’ (US), ‘PFR1’ and ‘PFR3’ (New Zealand), ‘EM_01’ (UK) and ‘G.11’ as a control for both trials. Part of the rootstocks (from dwarf and semi-dwarf rootstock trials) was planted in replanting conditions to test their tolerance to apple replant disease. All test trees came from the same nursery, and a common standardised evaluation protocol was used. Based on preliminary results averaged across sites, dwarf rootstocks can be ranked in terms of vigour in the following order: ‘EM_04’ < ‘EM_03’, ‘EM_05’ < ‘62-396-B10®’, ‘P 67’, ‘EM_02’, ‘G.11’ < ‘G.41’, ‘Cepiland-Pajam®2’ < ‘EM_06’, ‘PFR4’ < ‘PFR5’. On average, semi-dwarf rootstocks can be ranked in terms of vigour in the following order: ‘G11’ < ‘G.935’, ‘G.202’ < ‘PFR3’, ‘EM_01’ < ‘PFR1’. The highest cumulative yield in the young orchard was registered for trees on ‘PFR5’, ‘PFR4’, ‘G.11’, ‘G.41’, ‘Cepiland-Pajam®2’ and ‘EM_02’, while the lowest production was found for trees on ‘EM_04’. In the group of semi-dwarf rootstocks, the highest yield was on ‘PFR3’, ‘G.935’ and ‘PFR1’. Rootstocks also had a significant effect on fruit weight and fruit quality parameters. Results from the young orchards revealed interactions between sites and rootstock, potentially leading to site-specific rootstock choice based on the combination of rootstock, soil conditions and climate.
Abstract
No abstract has been registered
Authors
Mekjell Meland Milica Fotiric Aksic Oddmund Frøynes Almira Konjic Lejla Lasic Naris Pojskic Fuad GasiAbstract
In order to best conserve, as well as utilize, traditional apple germplasm in Norway, an apple heritage cultivar collection was established in Ullensvang, western Norway, which aims to become the National Clonal Germplasm Repository. The establishment of the apple heritage cultivar collection was preceded by a molecular study that aimed to genotype a large number of apple accessions maintained in various ex situ sites in western and south-eastern Norway, using a rather small set of eight SSR markers. However limited, the marker set managed to identify synonyms, homonyms, and duplicates within and among the investigated collections. In this study, 171 apple accessions from the Ullensvang apple heritage cultivar collection were genotyped using a set of 20 different SSR markers. Approximately half of the accessions have been previously genotyped using eight SSR markers, enabling an assessment of whether the use of a larger marker set would yield a more accurate characterization. Based on the obtained molecular data, the apple heritage cultivar collection was determined to hold a key part of the overall genetic diversity of the Norwegian apple germplasm. Furthermore, the twelve additional SSR markers were able to differentiate several accessions groups originally thought to be synonyms, as well as to provide a more detailed insight into the genetic structure of this germplasm.
Authors
Milena Ðorđević Tatjana Vujović Radosav Cerović Ivana Glišić Nebojša Milošević Slađana Marić Sanja Radičević Milica Fotirić Akšić Mekjell MelandAbstract
A study was conducted to investigate the effect of different storage periods and temperatures on pollen viability in vitro and in vivo in plum genotypes ‘Valerija’, ‘Čačanska Lepotica’ and ‘Valjevka’. In vitro pollen viability was tested at day 0 (fresh dry pollen) and after 3, 6, 9 and 12 months of storage at four different temperatures (4, −20, −80 and −196 °C), and in vivo after 12 months of storage at distinct temperatures. In vitro germination and fluorescein diacetate (FDA) staining methods were used to test pollen viability, while aniline blue staining was used for observing in vivo pollen tube growth. Fresh pollen germination and viability ranged from 42.35 to 63.79% (‘Valjevka’ and ‘Čačanska Lepotica’, respectively) and 54.58 to 62.15%, (‘Valjevka’ and ‘Valerija’, respectively). With storage at 4 °C, pollen viability and germination decreased over the period, with the lowest value after 12 months of storage. Pollen germination and viability for the other storage temperatures (−20, −80 and −196 °C) were higher than 30% by the end of the 12 months. Pollination using pollen stored at 4 °C showed that pollen tube growth mostly ended in the lower part of the style. With the other storage temperatures, pollen tube growth was similar, ranging between 50 and 100% of the pistils with pollen tubes penetrated into the nucellus of the ovule in the genotype ‘Čačanska Lepotica’. The results of these findings will have implications for plum pollen breeding and conservation.
Authors
Milica Fotiric-Aksic Biljana Rabrenovic U Gasic T Tosti D Dabic Zagorac M Natic Mekjell MelandAbstract
No abstract has been registered
Authors
Milica Fotiric-Aksic Biljana Rabrenovic U Gasic T Tosti D Dabic Zagorac M Natic Mekjell MelandAbstract
No abstract has been registered
Abstract
An intensive planting of ‘Celina’ pears on quince ‘Adams’ rootstock was established in May 2015 at NIBIO Ullensvang, western Norway. Five training systems (super spindles, trees with two leaders parallel to the row directions, slender spindles, and V-hedges of trees with 2 or with 4 leaders) were evaluated. Row distance was 3.5 m, and planting distance was 1.0 m except for super spindle trees and V-hedge with two leaders (0.5 m). Cultivars ‘Anna’ and ‘Fritjof’, used as pollinizers, were evenly distributed in the orchard and had good overlapping in flowering time. To get a faster establishment, the trees were headed back in winter 2016 when the formation of the different training systems was started. The first fruits were harvested in 2018. Due to unfavorable pollination conditions, fruit set in 2018 was very low. Average yields varied between 2.7 t ha‑1 for the super spindle trees to 10 t ha‑1 for the spindle trees. As a result of ample flowering and optimum pollination conditions, fruit set in 2019 was excellent, and average yields varied between 17 t ha‑1 for the 2-leader trees planted parallel to the row direction to 47 t ha‑1 for the 2-leader V-hedge trees. Fruit size was inversely related to fruit number per tree. Fruit weight depended on crop load per canopy volume and varied between 130 g for the two smallest trees (super spindles and 2-leader V-hedge system) and 180 g for the 2-leader trees planted parallel to the row direction. Soluble solid contents were high (11% on average), with no differences between training systems. After three cropping years, the spindle trees and V-hedge with 4 leaders per tree were the most productive systems per tree. However, the super spindle and 2-leader V-hedge system with twice the number of trees were the most productive systems per hectare.
Authors
Milica Fotirić Akšić Milica Nešović Ivanka Ćirić Živoslav Tešić Lato Pezo Tomislav Tosti Uroš Gašić Biljana Dojčinović Biljana Lončar Mekjell MelandAbstract
Using modern analytical techniques, a comprehensive study of the chemical composition of fruits from apple cultivars grown in Western Norway during 2019 and 2020 was done. Metals, sugars, organic acids, antioxidant tests, and polyphenol content have been observed. In all investigated samples, the most dominant sugars were glucose, fructose, and sucrose. Among 11 tested organic acids, the dominant was malic acid, followed by citric and maleic acid. The most common metal was potassium, followed by magnesium and zinc. The quantification of polyphenols showed that among the 11 quantified polyphenols, chlorogenic acid, quercetin 3-O-rhamnoside, quercetin 3-O-glucoside, quercetin, and phlorizin were the most abundant. A detailed study of the polyphenolic profile of nine investigated apple samples provided 30 identified polyphenolic compounds from the class of hydroxybenzoic and hydroxycinnamic acids, flavonoids, and dihydrochalcones. In addition to the identified 3-O-caffeoylquinic acid, its two isomers of 5-O-caffeoylquinic acid and three esters were also found. Present polyphenols of the tested apples provided significant data on the quality of Norwegian apples, and they contribute to the distinguishing of these apple samples.
Authors
Mekjell Meland Milica Fotiric-Aksic T Tosti U Gasic Nikola Horvacki Radoslav Cerovic Z TesicAbstract
No abstract has been registered
Authors
Mekjell Meland Milica Fotiric-Aksic T Tosti U Gasic Nikola Horvacki Radoslav Cerovic Z TesicAbstract
No abstract has been registered
Abstract
Denne rapporten omhandlar resultat frå kartlegging av næringsstatusen i norske eplehagar. Jord,- blad og fruktprøvar vart samla inn frå ulike eplehagar på Aust- og Vestlandet med variasjon i jordart, innhald og type organisk materiale i åra 2018-2020. Føremålet var å studera samanhengane mellom plantefysiologiske sider i epletreet relatert til jorda, treveksten, avling og fruktkvalitet. Resultat frå det treårige studiet om verknaden av gjødselpraksisar på opptak av mineral i blada, avling og fruktkvallitet hjå ulike eplesortar frå fire regionar er samla i denne rapporten. This report is summarizing results from a survey analyzing the nutrient levels in fruit trees and soil in four fruit growing regions in Norway during the seasons 2018-2020. The aim was to study the relationship between main plant physiological principles in the tree, related to the soil, tree growth, yield, fruit quality, and fruit storage. The results of a three-year study of apple tree fertilization practices on orchard soil fertility, leaf mineral composition, apple tree yields and fruit quality of several apple cultivars in four main apple producing regions in Norway are compiled in this report.
Abstract
This study evaluated the effective pollination period (EPP) in four European plum (Prunus domestica L.) cultivars (‘Mallard’, ‘Edda’, ‘Jubileum’, and ‘Reeves’) during two years (2018–2019) under the environmental conditions in western Norway. The pollination of plum cultivars was carried out one, three, five, seven, and nine days after anthesis (DAA) with a pollen mix of two compatible cultivars (‘Victoria’ and ‘Opal’). Initial, middle-season, and final fruit set was recorded after one month and two months after pollination and just before the harvest, respectively. On average from both years cultivar ‘Jubileum’ had the highest fruit set when pollinated one, three, five, seven, and nine DAA (33.23%, 30.83%, 8.47%, 3.08%, and 1.15%, respectively), which was more than two folds higher fruit set than in the other studied cultivars. Cultivar ‘Jubileum’ showed significantly reduced fruit set between pollination on five and nine DAA, while cultivars ‘Mallard’, ‘Edda’, and ‘Reeves’ had markedly reduced fruit set if pollinated three to five DAA, implying that the EPP in ‘Jubileum’ was five days while in the rest it was three days. Variation of weather conditions during the flowering period in both years did not have a major effect on the receptivity of stigmas in the studied plum cultivars, which means that the existing differences in the length of EPP is maternal-genotype dependent.
Abstract
No abstract has been registered
Abstract
No abstract has been registered
Abstract
Compatibility and synchrony between specialized tissues of the pistil, female gametophytes and male gametophytes, are necessary for successful pollination, fertilization, and fruit set in angiosperms. The aim of the present work was to study the development and viability of embryo sacs, as well as fertilization success, in relation to the fruit set of the cultivars ‘Mallard’, ‘Edda’, ‘Jubileum’, and ‘Reeves’, under specific Norwegian climatic conditions. Emasculated, unpollinated, and open-pollinated flowers were collected at the beginning of flowering, and on the 3rd, 6th, 9th, and 12th days after flowering, from all four plum cultivars over two years (2018/2019). Ovaries were dehydrated, embedded in paraffin wax, sectioned, stained, and observed under a light microscope. Results showed the existence of synchronization between successive phases in the development of the embryo sac and individual phases of flowering. All plum cultivars had higher percentages of viable embryo sacs, fertilized embryo sacs, and fruit set in 2018 than in 2019. These differences may be related to the very low temperatures during the post-full-flowering period in 2019, and to the low adaptation of some studied cultivars to unfavorable conditions. In our study, the cultivar ‘Jubileum’ showed the highest percentage of viable embryo sacs, fertilized embryo sacs, and fruit set compared to other cultivars, i.e., the best low-temperature adaptation.
Abstract
No abstract has been registered
Abstract
No abstract has been registered
Authors
Dragana Skočajić Uroš Gašić Dragana Dabic´ Zagorac Marija Nešić Živoslav Tešić Mekjell Meland Milica Fotirić AkšićAbstract
The aim of this study was to prove that under in vitro conditions, the adhesiveness of the callus between rootstock and scion, the development of callus cells at the points of fusion, and the presence of phenolic components are closely related to the level of (in) compatibility of the grafting combinations between Sato-zakura cherry cultivars (‘Amanogawa’, ‘Kanzan’, and ‘Kiku-shidare-zakura’) and commercial rootstocks. Prunus avium, Prunus ‘Colt’, Prunus mahaleb and Prunus serrulata were used as compatible and Prunus serotina and Pyrus communis ‘Pyrodwarf’ were used as two potentially incompatible rootstocks. The results indicated the significant manifestations of the early signs of the incompatibility on the callus junction. Phenols, as well as tissue senescence, were very precisely localized by toluidine blue and alcian blue as well as safranin staining, which can indicate the early signs of the callus incompatibility in some grafting unions. In the callus unions of Prunus avium with ‘Amanogawa’ and ‘Kiku-shidare-zakura’ the results of chemical analyses indicated that the existence of several flavonols, flavones and phenol acids could be involved in the incompatibility process in grafted combination. The detection of flavonol astragalin in the unions can be a biomarker of compatibility between scion and the rootstock, while some polyphenols, such as neochlorogenic acid, sinapic acid, ellagic acid, caffeic acid, baicalein, naringenin, apigenin and luteolin can be used as the indicators of graft incompatibility. p-coumaric acid and ferulic acid could be used for detection of delayed incompatibility.
Authors
Milica Fotiric Aksic Kristina Lazarević Sandra Šegan Maja Natić Tomislav Tosti Ivanka Ćirić Mekjell MelandAbstract
Apple production generates large amounts of apple pomace including seeds, leading to high transportation costs, public health hazards and undesirable odor. A new reuse strategy of this kind of waste could solve environmental issues and/or create unconventional sources of health beneficial products. In total, seeds from 75 apple cultivars grown in Norway (both domestic and international) have been analyzed for the first time for oil content and fatty acid profile together with tocopherols and carotenoids quantification in defatted seeds. Seeds from cultivar Håkonseple had the highest oil content (22.10%), with linoleic, oleic acid, and palmitic acid as the most abundant fatty acids. The levels of β-carotene and lycopene carotenoids and α-tocopherol were the highest in defatted seeds of the cultivar Sureple Grøn. Principal component analysis separated cultivars according to the total oil content. The Norwegian apple cultivars Håkonseple, Kviteple, Tolleivseple, Vinterrosenstrips, and Tokheimseple are recommended for obtaining vegetable oil due to their high oil contents, while cultivar Sureple Grøn can be separated due to its high levels of β-carotene, lycopene and total tocopherols.
Abstract
No abstract has been registered
Authors
Ivanka Ćirić Milica Sredojević Dragana Dabić Zagorac Milica Fotirić-Akšić Mekjell Meland Maja NatićAbstract
Berry fruits (such as strawberry – Fragaria × ananassa, raspberry – Rubus idaeus, blackberry – Rubus fruticosus, currants – Ribes sp., blueberry – Vaccinium sp., and many others) are known for their health benefits due to their richness in sugars, acids, vitamins, minerals, phenolics, and other nutrients. However, their contents are influenced by various factors, such as species, berry cultivar, ripeness, geographical origin, and growing conditions, and the type of extraction and processing of raw seed material. Generally, the berry industry for juice and fruit-wine production produces vast amounts of by-products (mostly seeds). Since berry seeds contain lipids, these by-products are very interesting as a raw material for oil production. As berry seed oil production generates certain waste, strategies towards reducing and valorizing need to be developed. Unlike beery fruits and berry seed oil, whose composition has been tested many times so far, berry seed oil by-products were the subject of a small number of published papers. Due to chemical richness and heterogeneity, it is expected that berry seed oil by-products to be promising natural bio-resource. Still, it is necessary to consider how many other biologically valuable compounds remain in seed waste.
Abstract
Persian walnut (or English walnut) growing dates back to 7000 BC in Persia, a gene center of Juglans regia L. The top leading countries in walnut production are China, the USA, and Iran accounting for ~75% of world production. Nuts are an essential component in human nutrition because their consumption provides the required amount of energy (720 kcal per 100 g of fruits), unsaturated fatty acids, carbohydrates, proteins, fibers, sterols, tocopherols, minerals (K, P, Ca, Mg, and Na), volatiles, and other bioactive constituents. In addition, walnut kernels are rich in oil (50–70%) and protein, depending on the cultivar, location, and irrigation rate. Although mostly consumed raw, walnut kernels are increasingly processed by cold pressing into light yellow edible oil used in foods as flavoring, like salad dressings or cooking. Walnut oil is especially valued for its high content of essential fatty acids (linoleic and linolenic acids) and micronutrients such as phytosterols, squalene, and other tree nut oils polyphenols, and tocopherols. As by-products, both shell and cold-pressed cake from walnut that remains after the cold pressing process of oil can be used in various ways (food, cosmetics, pharmaceutical products, or textile industry). Especially residual walnut press cake is practical when used in food and in pharmacy, mostly integrated into other products. The reason for treating residual cake as a value-added product lies in the fact that defatted cake is generally rich in polar phenolic compounds and, as a source of natural antioxidants, is expected to show significant antioxidant activity. The most abundant polyphenols found in walnut oil cake are hydrolyzable tannins. In addition, press cake is rich in dietary fiber, protein, residual oil, polyunsaturated fatty acids, and tocopherol, all considered health-enhancing components. Therefore, by using walnut oil cake as a low-cost product, many aspects connected with the valorization of food wastes are covered, such as consumers' dietary habits, economy, and environmental protection.
Authors
Nermina Spaho Fuad Gasi Erich Leitner Milenko Blesić Asima Akagic Sanja Orucevic Zuljevic Mirsad Kurtovic Davorka Dukic Ratkovic Mirela Smajic Murtic Milica Fotiric Aksic Mekjell MelandAbstract
This study was conducted with the aim of developing fruit spirits by utilizing old (autochthonous) apple and pear cultivars that can be attractive to both consumers and producers. Consumers of spirits could enjoy the unique flavor, and producers could gain an opportunity for brand development. In total, eight old apple cultivars (Sarija, Žuja, Samoniklica, Prijedorska zelenika, Bobovec, Masnjača, Lijepocvjetka, and Šarenika) and three pear cultivars (Budaljača, Krakača, and Kalićanka) from Bosnia and Herzegovina were used for the spirits production and for characterizing the flavor of distillates. Golden Delicious was used as a representative of commercial apple cultivar. The aroma profile was conducted through the identification of minor volatile organic compounds (VOCs) and the sensory perception of spirits. Analysis of the VOCs was performed by gas chromatography mass spectroscopy (GC/MS) techniques after enrichment via solid-phase microextraction (SPME). Sensory evaluation was performed by 12 trained panelists. Overall, 35 minor volatile compounds were found in spirits: 13 esters, 7 alcohols, 6 acids, 5 terpenes, and 4 aldehydes. Significant differences were detected in the distribution and quantity of the VOCs, which were fruit cultivar-dependent. Spirits made from Šarenika apple cultivar showed the largest amount of all acids, especially short- and medium-chain fatty acids; however, this richness was not correlated with pleasant sensory attributes. Spirits obtained from Prijedorska zelenika and Masnjača apple cultivars had the best sensory attributes. Budeljača and Krakača pears are promising cultivars as flavoring in spirits production.
Abstract
No abstract has been registered
Abstract
No abstract has been registered
Abstract
No abstract has been registered
Authors
Mekjell MelandAbstract
No abstract has been registered
Authors
Darius Kviklys V. Abukauskas Mekjell Meland Walter Guerra I. Høller Nicola Dalabetta T. Pantezzi J. Carbo J. Lordan A. Karlstrøm Filicidad Fernandez Fernandez M. Bruggenwirth L. Lanar M. Meszaros T Ruhmer S Perren S Cia S Codarin V. Mathieu F. Bernard P Bielicki L Manfrini L Corelli Grapadelli Ann Gomand Jef VercammenAbstract
No abstract has been registered
Abstract
Norwegian pear (Pyrus communis L.) production has been in decline for the last 25 years. This was mainly because of old cultivars, with low yields and poor consumer appeal, could not compete against strong competition from imported pears, mainly ‘Conference’. Since 1994, the Norwegian breeding company, Graminor Ltd., has released several new pear cultivars, which have been evaluated at NIBIO Ullensvang, western Norway. The first trial was planted in 1999 and included the Graminor Ltd. cultivars: ‘Ingeborg’, ‘Fritjof’ and ‘Anna’, which were bred by the Norwegian University of Life Sciences. In 2002, a second trial was planted including Graminor Ltd. cultivars: ‘Kristina’, ‘Ingrid’ and ‘Celina’ and these were compared against a control, ‘Clara Frijs’. All scion cultivars were grafted on the semi-vigorous rootstock ‘Brokmal’ and grown for 8 years. In both trials, full bloom (~80% of flowers open) took place between 7 May + 3 days and 15 May + 4 days. Flowering was however, completed within a 7-day period in any one year, ensuring adequate overlap in flowering time between all cultivars. Over the final 4-year period all cultivars were evaluated, ‘Anna’, ‘Fritjof’, ‘Kristina’ and ‘Ingeborg’ all had moderate cumulative yields (64.7, 66.2, 36.1, and 30.4 kg·tree-1, respectively). Fruit weight (212 to 183g) and quality of all these cultivars was acceptable (11.2% ≤ TSS ≤ 11.8%; 0.16% ≤ acidity ≤ 0.22%). However, ‘Fritjof’ had many misshapen fruit and exhibited pre-harvest shriveling in several instances making it unacceptable for commercial plantings. ‘Clara Frijs’ and ‘Celina’ cumulative yields were low (12.5 and 21.2 kg per tree, respectively) and fruit were also small (172 to 161 g, respectively). However, due to the attractive cerise-blush ‘Celina’ (trademarked QTee®) pear is now widely planted in Norway and abroad and grafted on Quince rootstocks.
Abstract
No abstract has been registered
Abstract
No abstract has been registered
Abstract
No abstract has been registered
Abstract
No abstract has been registered
Abstract
No abstract has been registered
Abstract
No abstract has been registered
Abstract
No abstract has been registered
Abstract
No abstract has been registered
Abstract
The objective of this study was to determine morphological and anatomical leaf characteristics and stomatal traits of three European (Pyrus communis L.) cultivars, three Asian [Pyrus pyrifolia (Burm. f.) Nakai] pear cultivars together with one interspecies hybrid (P. pyrifolia × P. communis ‘Bartlett’) and link them with the resistance to pathogens. Pear trees were grown under the standard practice without irrigation. Fully developed leaves were picked from the middle part of the extension shoots at the beginning of the July. Leaf traits were measured on leaves picked the same day. Anatomy of leaves was determined under light microscopy (LM) while scanning electron microscopy (SEM) was used for the examination of the stomata cells. Asian pear cultivars (‘Kousui’, ‘Nijisseiki’ and ‘Niitaka’) had much higher leaf parameters (width, length, stem length and leaf area) than the European cultivars (‘Conference’, ‘Williams Bartlett’, ‘Abbate Fetel’) and interspecies hybrid (‘Kieffer Seedling’). Midrib parameters (length and width) were the highest in ‘Kosui’ and ‘Nijisseiki’. Leaves of ‘Kieffer Seedling’ and ‘Abbate Fetel’ were the thickest, mainly due to increased palisade and spongy parenchyma thickness. The leaf stomata density significantly varied among the pear cultivars, ranging from 89.53 stomata mm‑2 (‘Nijisseiki’) up to 134.07 stomata mm‑2 (‘Housui’). SEM proved that Asian pear cultivars and ‘Kieffer Seedling’ shared ‘paracytic’ stomata type, while European pear cultivars had ‘anomocytic’ stomata type. Cluster analysis distinguished pear cultivars into two distinct groups, where European cultivars formed first sub-cluster and Asian together with ‘Kieffer Seedling’ second sub-cluster. Midrib traits and stomata type made a clear separation between the clusters. These results might suggest that thickness of midrib could be a huge barrier for Psylla sp. probing in Asian pears, thus representing one of the key factors in the resistance of these cultivars.
Abstract
Denne rapporten gjev eit litteraturoversyn ved ulike sider av næringsopptaket av ulike mineral og tilførsel til epletre. Det er omtalt dei fysiologiske sidene av næringsopptaket hjå grunnstammer og sjølve sorten, transporten gjennom sil- og vedvev og funksjonen til dei ulike minerala i epletreet. Bladanalysar er eit viktig diagnoseverktøy for vurdering av næringsstatusen i treet. Terskelverdiar for dei ulike minerala er vurderte og tiltak for å retta opp eventuelle mangelsymptom ved hjelp av eit bladgjødslingsprogram. Tilsvarande er eigenskapar ved jorda vurderte, normer for jordanalysar omtalte og tilråding om kalking. Siste bolken omhandlar ulike måtar og mengder for å tilføra gjødsel til frukthagen. Dette gjeld gjødsling til jorda, gjødselvatning i dropevatningsystemet i trerekkja og bladgjødsling.
Abstract
Performance of the Quince rootstocks ‘Adams’, ‘C’ and ‘Eline®’, all grafted with pear cultivars ’Celina’, ‘Ingeborg’ and ‘Kristina’, were compared at the experimental farm of NIBIO Ullensvang, western Norway. Tree vigour, yield, fruit size and fruit quality were evaluated annually for the first seven years. No severe winter damage was observed during these years and none of the trees died. After seven years there were no significant differences in tree size in ‘Celina’ and ‘Ingeborg’ grafted on the different rootstocks, while trunk diameter increase of ‘Kristina’ was significantly larger on ‘Eline®’ than on ‘C’ and intermediate on ‘Adams’. Flower development and fruit set were not affected by rootstocks in any of the three scion cultivars. On average, mature fruit were picked during mid to end September and the trees began producing a small crop in the third season. No alternate bearing pattern was identified. For ‘Celina’ and ‘Kristina’ yield was similar for trees on all three rootstocks. Cumulative yields for the first five cropping years were 31.3 kg tree‑1 for ‘Celina’, 25.9 kg tree‑1 for ‘Kristina’ and 19.4 kg tree‑1 for ‘Ingeborg’. ‘Celina’ produced the highest total number of fruit when grafted on ‘Adams’ or ‘C’. Trees on ‘Eline®’ produced a significantly lower number of fruit in both ‘Celina’ and ‘Ingeborg’. On average for all cultivars, no significant effect of rootstock was observed on average fruit weight during these 5 production years. ‘Eline®’ on average yielded fruit of 165 g for all cultivars while for ‘Adams’ and ‘C’ it was 162 g. Soluble solids concentration was high (11.2% on average) but was not significantly affected by rootstocks. Fruit acidity was similar for all quince rootstocks (0.19-0.21%). The fruit development period between full bloom and harvest showed a clear inverse linear relationship with the average daily temperature. In conclusion, because the trees have not reached their full production none of these quince rootstocks can yet be recommended as the preferred rootstock for pear growing in a cool, mesic northern climate.
Abstract
In total 14 cherry cultivars and advanced selections released by the Pacific Agri-Food Research Centre (PARC-Summerland), Agriculture and Agri-Food Canada were tested at NIBIO Ullensvang during 2010-2016. The scions were grafted on the dwarfing Gisela 5 rootstock and planted in high tunnels. Main phenological, vegetative growth and productivity characteristics and fruit quality parameters were evaluated and detailed information about the different cultivars and selections are presented. After comprehensive studies the cultivars ‘SPC 108’ and ‘Starblush’ are recommended for commercial fruit growing in Norway in addition to the main cultivar ‘Lapins’. ‘SPC 107’ is recommended for home gardens. The selection SPC 263 and ‘Sofia’ showed outstanding fruit quality parameters, but had low productivity due to stunted tree growth. Grafting on more vigorous rootstocks than Gisela 5 is recommended.
Abstract
The Norwegian newly bred pear cultivar, ‘Celina/QTee®’, which was launched in 2010, has been released from the Norwegian breeding program. It derived from the combination ‘Colourée de Juillet’ × ‘Williams’. In Norway the flowering is medium to late in May and it ripens in the beginning of September. It has large attractive fruits with red blush and good fruit quality, storability and shelf life. Significant areas of ‘Celina’ cultivars are planted in other countries, mainly Europe. Generally, unfavourable environmental conditions for pear pollination during the Nordic spring can have a very negative effect on the yields in Norwegian pear orchards. Therefore, it is of considerable importance to interplant multiple suitable pollinizer genotypes together with the main cultivar. In order to find the right pollinizers besides following biology of fertilization, pollinizing efficacy using microsatellites were studied at NIBIO Ullensvang, western Norway. In this study, during 2017, seeds from fruits of the pear cultivar ‘Celina’ were extracted. The fruits were randomly harvested from five different orchards located in Ullensvang including NIBIO. Alongside the seeds, leaves were taken from the mother cultivar (‘Celina’) and five pear pollinizer cultivars presented in the orchards (‘Fritjof’, ‘Kristina’, ‘Clara Frijs’, ‘Herzogine Elsa’ and ‘Anna’). Using 11 microsatellite markers, a genetic characterization was conducted on both the seeds and the leaves. The obtained SSR profiles were used for gene assignment analyses. The results of the genetic analyses indicate a very heterogeneous situation regarding pollination. In conclusion, ‘Fritjof’, ‘Kristina’, ‘Clara Frijs’, ‘Herzogine Elsa’ and ‘Anna’ pears had different pollen contributions as pollinizers to ‘Celina’ depending on the investigated orchard. Only one cultivar (‘Herzogine Else’) could be singled out as a major pollen contributor in more than two orchards. Genetic analyses will be repeated in the same orchards, during an additional season, after which more conclusive results will be available.
Abstract
Denne rapporten omhandlar resultat frå feltforsøk med epletre i vekstsesongane 2016 - 2020 ved NLR Viken i Lier og NIBIO Ullensvang. Føremålet med dette prosjektet var å stimulera til auka produksjon av norske eple med god fruktkvalitet dyrka på ein effektiv måte. Det vart gjennomført feltforsøk med kjemisk tynning under blomstringa og på karten med bruk av ulike bioregulatorar, mekanisk tynning med maskin under blomstringa, rotskjering med kniv påmontert traktor, utprøving av vekstregulatoren Regalis og gjødselvatning til to eplesortar. Kontrollert gjødseltilføring med epletre i potter i plasthus vart gjennomført ved Nibio Særheim. Målsetjinga heile tida var å gjera forsøk med miljøvennlege teknikkar til å gjødsla epletre optimalt for å auka den generelle fruktkvaliteten og heva andelen av årleg klasse 1 kvalitet. Dessutan var det viktig å nytta bærekraftige metodar for å redusere skotveksten og regulera avlinga i trea for å oppnå rett fruktsetjing under norske vilkår.
Authors
Teresa Barreneche Maria Cárcamo de la Concepción Marine Blouin-Delmas Matthew Ordidge Hilde Nybom Gunars Lacis Daina Feldmane Jiri Sedlak Mekjell Meland Hedi Kaldmae Kersti Kahu Zsuzsanna Bekefi Sanda Stanivukovic Gordana Đurić Monika Høfer Martin Galik Elisabeth Schüller Andreas Spornberger Sorina Sirbu Pavlina Drogoudi Ana Christina Agulheiro-Santos Ossama Kodad Ales Vokurka Marc Lateur Felicidad Fernandez Fernandez Daniela Giovannini José Quero-GarcíaAbstract
Sweet cherry (Prunus avium L.) is a temperate fruit species whose production might be highly impacted by climate change in the near future. Diversity of plant material could be an option to mitigate these climate risks by enabling producers to have new cultivars well adapted to new environmental conditions. In this study, subsets of sweet cherry collections of 19 European countries were genotyped using 14 SSR. The objectives of this study were (i) to assess genetic diversity parameters, (ii) to estimate the levels of population structure, and (iii) to identify germplasm redundancies. A total of 314 accessions, including landraces, early selections, and modern cultivars, were monitored, and 220 unique SSR genotypes were identified. All 14 loci were confirmed to be polymorphic, and a total of 137 alleles were detected with a mean of 9.8 alleles per locus. The average number of alleles (N = 9.8), PIC value (0.658), observed heterozygosity (Ho = 0.71), and expected heterozygosity (He = 0.70) were higher in this study compared to values reported so far. Four ancestral populations were detected using STRUCTURE software and confirmed by Principal Coordinate Analysis (PCoA), and two of them (K1 and K4) could be attributed to the geographical origin of the accessions. A N-J tree grouped the 220 sweet cherry accessions within three main clusters and six subgroups. Accessions belonging to the four STRUCTURE populations roughly clustered together. Clustering confirmed known genealogical data for several accessions. The large genetic diversity of the collection was demonstrated, in particular within the landrace pool, justifying the efforts made over decades for their conservation. New sources of diversity will allow producers to face challenges, such as climate change and the need to develop more sustainable production systems.
Abstract
No abstract has been registered
Abstract
No abstract has been registered
Abstract
No abstract has been registered
Abstract
No abstract has been registered
Abstract
No abstract has been registered
Abstract
NIBIO Ullensvang har i perioden 2012-2019 gjennomført rettleiingsprøving av samla 11 eplesortar og -seleksjonar. Føremålet var å skaffa norske fruktdyrkarar sortar som gjev stor avling med kvalitetsfrukt og er tilpassa det norske klimaet. Sortane vart poda på den svaktveksande grunnstamma M9. Pomologiske karakterar og fruktkvalitet vart vurderte og detaljert informasjon om dei ulike sortane er gjeve i denne rapporten. Sortane Asfari og Elstar Boerekamp Excellent- Star® vert tilrådde til kommersiell fruktdyrking. Sorten Tiara kan dyrkast til jus og som dekorasjonsfrukt sidan den har raudt fruktkjøt. Sorten Pinova bør prøvast vidare. På grunn av svak fruktkvalitet og sein modning er fylgjande sortar og utval ikkje tilrådde for dyrking under norske tilhøve: 1/05, 58/06, A 75, Galmac, Jugala, Crimson Crisp og Elshof.
Abstract
Norwegian plum production is characterized by climatic limitations, different flowering time, deficiently of wholly-adapted cultivars and appropriate pollen donors for cultivars that can be grown in this region. This study evaluated the progamic phase of fertilization and fruit set in four European plum cultivars (´Mallard´, ´Edda´, ´Jubileum´, and ´Reeves´) after crossing with different pollinizers over two years (2018/2019). Reproductive parameters, in vitro pollen germination, number of pollen tubes in the upper part of the style and locule of the ovary, number of pistils with ovule penetrated by pollen tube, fruit set in all crossing combinations, and fruit set in open pollination of pollen recipient cultivars showed different adaptability of both recipient and donor cultivars to the specific ecological conditions prevailing in Western Norway. The pollinizers ´Victoria´, ´Opal´ and ´Č. Lepotica´ proved to be a very good pollinizers for cultivar ´Jubileum´, while pollinizers ´R. C. Souffriau´ and ´Valor´ for the cultivar ´Reeves´. Cultivars ´Opal´, ´R. E. Prolific´ and ´Mallard´ are excellent pollinizers for ´Edda´ in conditions of higher temperatures during flowering period and post-flowering period. Cultivar ´Č. Lepotica´ proved to be the best pollinizer for ´Edda´ in conditions when the temperatures were lower. Cultivars ´Opal´ and ´R. E. Prolific´ can be considered as good pollinizers for ´Mallard´.
Abstract
No abstract has been registered
Authors
Maja Natic Dragana Dabic Zagorac Ivanka Ciric Mekjell Meland Biljana Rabrenovic Milica Fotiric AkšicAbstract
No abstract has been registered
Abstract
Nibio Ullensvang har i perioden 2010-2016 gjennomført rettleiingsprøving av samla 14 sortar og seleksjonar av søtkirsebær frå foredlingsprogrammet ved forskingsstasjonen Summerland i Canada. Føremålet var å skaffa norske fruktdyrkarar sortar som gjev stor avling med kvalitetsfrukt og er tilpassa det norske klimaet. Sortane vart poda på den svaktveksande grunnstamma Gisela 5 og vart planta i ein plasttunnel. Pomologiske karakterar og fruktkvalitet vart vurderte og detaljert informasjon om dei ulike sortane er gjeve i denne rapporten. Sorten Starblush og seleksjonen SPC 108 er tilrådd for dyrking under norske tilhøve i tillegg til hovudsorten Lapins. Seleksjonen SPC 107 høver godt i småhagar.
Abstract
Apples are an important source of bioactive compounds, especially mineral nutrients. Minerals (both macro- and micro-elements) are responsible for the functioning of the human body, and involved in the metabolism and production of carbohydrates, lipids, proteins, vitamins and enzymes. The objective of this study was to determine and compare the content of some minerals (K, P, Ca, Mg and Fe) of two different apple cultivars (‘Red Aroma Orelind’ and ‘Discovery’), both in peel and pulp, grown in organic and integrated production systems in western Norway in 2015. Samples of fruits were prepared by microwave digestion using an Ethos 1 microwave system. All analyses were performed in triplicate on a Thermo Scientific iCAP 6500 Duo ICP. The results showed that potassium was found in the largest quantity in both apple cultivars and in both management systems and average concentration was 944.3 µg g-1 of fresh weight (FW). Calcium was in second place with average of 180.6 µg g-1 FW. Both apple cultivars had largest amounts of both K and P (in peel and flesh) from organic production compared to fruits coming from the integrated production system. The cultivar ‘Red Aroma Orelind’ had a significantly higher level of Fe in organic fruits compared to integrated. The present study showed that the highest values of K/Ca, (K+Mg)/Ca and Mg/Ca were obtained from the cultivar ‘Discovery’ under organic production (both in peel and flesh). Regarding significantly higher concentrations of P, K, Mg, Fe and balanced mineral ratios in organic apples, it can be concluded that those fruits have higher quality, and are at lower risk of bitter pit when stored.
Abstract
Since the European pear (Pyrus communis L.) is a self-incompatible fruit species, synchrony and compatibility between female parts of the mother plant and male gametes from the pollen donor must be fulfilled. Besides pollination and fertilization, normal embryo and zygote development is one of the prerequisites for the satisfactory yields in pears. The main goal of this experiment was to investigate the functionality of embryo sacs and the embryo’s early stages of growth in relation to the fruit set of diploid (‘Celina’) and the triploid (‘Ingeborg’) pear cultivars under specific Norwegian climatic conditions. For this purpose, flowers were collected at the beginning of flowering, and on the third, sixth, ninth, and twelfth days after the beginning of this phenophase for two consecutive years. Ovaries were dehydrated, embedded in paraffin wax, sectioned, stained, and observed under the light microscope. In the analyzed cultivars, results showed different tendencies in embryo sac development and degradation processes, in both experimental years, which is probably due to the genetic background of the examined cultivars. Also, fertilization success and fruit set were higher in the second year of study due to the higher average temperature during the flowering period. Diploid cultivar ‘Celina’ showed much better adaptation to high temperatures in relation to triploid cultivar ‘Ingeborg’.
Authors
Mekjell Meland Oddmund Frøynes Milica Fotiric Akšic Naris Pojskic Belma Kalamujic Stroil Lejla Lasic Fuad GasiAbstract
European plum cultivars (Prunus domestica L.) are hexaploid and partially self-fertile or self-sterile requiring compatible pollinizers with overlapping bloom times. Therefore, inter-planting of different pollinizer cultivars is recommended. In order to identify successful pollinizers of the plum cultivars ‘Edda’, ‘Opal’ (self-fertile), ‘Jubileum’, ‘Reeves’, ‘Mallard’, ‘Avalon’, ‘Cacanska Lepotica’ (self-fertile), and ‘Valor’, 60 fruits per cultivar were collected from nine orchards in 2017 and 2018, all of which were located in Ullensvang, western Norway. DNA extraction was subsequently conducted from the obtained embryos, followed by genetic characterization using seven microsatellite markers. Tissue samples from all possible pollinizers were collected during the summer of 2017 and the same DNA approach was conducted. Results showed that ‘Opal’ was the most successful pollinizer among the investigated plum cultivars. The main exception was ‘Cacanska Lepotica’, which consistently displayed very high level of self-pollination. The most successful foreign pollinizer of ‘Opal’ was ‘Mallard’. However, in more than two thirds of embryos extracted from ‘Opal’ fruits self-fertilization was determined. ‘Reeves’ was identified as the most successful pollinizer among embryos collected from ‘Valor’. Among the five cultivars (‘Edda’, ‘Jubileum’, ‘Reeves’, ‘Mallard’, and ‘Avalon’) that did not display self-pollination, the pollinizer success rate of ‘Opal’, ranged from 36.5% (‘Mallard’) to 93.5% (‘Edda’) in 2017, while in 2018 this rate ranged from 43.5% (‘Jubileum’ and ‘Reeves’) up to 96.5% (‘Edda’). Overall, genotyping embryos using SSRs (simple sequence repeats) proved an effective method in determining the success rate of individual pollinizers among European plum cultivars.
Abstract
In order to identify successful pollinizers of plum cultivars ‘Edda’ and ‘Opal’, 60 mature open pollinated fruit were collected from these two cultivars in autumn 2017. The fruits were harvested in three different orchards located in Ullensvang, the main fruit production area in Norway. After the harvest, kernels were separated from the fruit and used for the extraction of single embryos located within each kernel. At the same time, leaves were collected from the plum cultivars ‘Edda’ and ‘Opal’, as well as from all other plum cultivars present at the location and nearby orchards (‘Mallard’, ‘Jubileum’, ‘Reeves’, ‘Avalon’, ‘Valor’, ‘Cacanska Lepotica’ and ‘Herman’). DNA extraction was carried out for the embryos and leaves, and were used for genotyping using seven microsatellite markers. The microsatellite data were used for conducting paternity analyses based on a log likelihood ratio, where the fingerprint information from the leaves were the possible pollen donors available at the location. The results revealed within all examined orchards that the most successful pollinizer of ‘Edda’, a self-sterile cultivar, was ‘Opal’. The most successful foreign pollinizer of ‘Opal’ was ‘Mallard’. However, more than two thirds of embryos extracted from ‘Opal’ fruits did not present any alleles not already identified in ‘Opal’, which was expected considering that this plum cultivar was known to be self-fertile. European plums are hexaploid making its allele callings and paternity tests rather complicated. However, the approach used in this study gave clear answers regarding the most successful pollinizers.
Abstract
No abstract has been registered
Abstract
The triploid pear cultivar ‘Ingeborg’ is currently the main commercial pear cultivar grown in Norway. However, fruit set and subsequent yields of this cultivar have proven to be variable and overall rather low. In order to promote the fruit set, different bioregulators were applied during and after bloom and compared with an untreated control. Investigations were done during the period 2017-2018, at NIBIO Ullensvang, western Norway. Different dosages of both gibberellins (GA3, trade name GIBB 3, 10% active ingredient (a.i.) and GA4/7, trade name Novagib®, 1% a.i.) were applied at full bloom and at petal fall. Additional applications of the growth retardant prohexadioneCa (trade name Regalis®, 10% a.i.) were applied twice, when bourse shoots had 3-5 leaves and after one month later. Ethephon (Cerone (480 g a.i. L-1)) was applied three times starting about 7 days after petal fall with ca. 7- to 10-day intervals. All gibberellin applications significantly increased fruit set compared to the untreated control. One single application with GA3 (3 g ha-1) almost tripled the fruit number per 100 flower clusters when compared with the control (136 and 46, respectively). The yield response was similar (16.8 to 9.6 kg tree-1, respectively). Similar results occurred with one application of GA4/7 (12 g ha-1) with the same crop load level, and the fruit weights were similar to the control (130 g). Prohexadione-Ca treatments significantly reduced shoot growth of the pear trees. Two treatments with 125 g ha-1 or one treatment of 250 g ha-1 reduced the growth by ~35% but had no significant effect on fruit set and yield. The multiple ethephon applications (275 mL ha-1 in total) had no effect on both set and shoot growth, and return bloom compared to the untreated or gibberellin treated trees.
Authors
Anita Smailagic Petar Ristivojevic Ivica Dimkic Tamara Pavlovic Dragana Dabic´ Zagorac Sonja Veljovic Milica Fotiric´ Akšic Mekjell Meland Maja NaticAbstract
The main focus of this study is to assess radical scavenging and antimicrobial activities of the 11 wood extracts: oak (Quercus petraea (Matt.) Liebl., Q. robur L., and Q. cerris L.), mulberry (Morus alba L.), myrobalan plum (Prunus cerasifera Ehrh.), black locust (Robinia pseudoacacia L.), and wild cherry (Prunus avium L.). High-performance thin-layer chromatography (HPTLC) provided initial phenolic screening and revealed different chemical patterns among investigated wood extracts. To identify individual compounds with radical scavenging activity DPPH-HPTLC, assay was applied. Gallic acid, ferulic and/or caffeic acids were identified as the compounds with the highest contribution of total radical scavenging activity. Principal component analysis was applied on the data set obtained from HPTLC chromatogram to classify samples based on chemical fingerprints: Quercus spp. formed separate clusters from the other wood samples. The wood extracts were evaluated for their antimicrobial activity against eight representative human and opportunistic pathogens. The lowest minimum inhibitory concentration (MIC) was recorded against Staphylococcus aureus for black locust, cherry and mulberry wood extracts. This work provided simple, low-cost and high-throughput screening of phenolic compounds and assessments of the radical scavenging properties of selected individual metabolites from natural matrix that contributed to scavenge free radicals.
Abstract
The aim of this study was to evaluate the thinning efficacy of metamitron (Brevis®) as fruitlet thinner compared to ammonium thiosulphate (ATS) and ethephon (Cerone) as flower thinning agents to ‘Rubinstep’ apple. The thinning efficacy of the flower thinning agents was compared to different timings (8-10 and 12-14 mm fruitlet diameters) and dosages (165 and 330 ppm) of the fruitlet thinner metamitron at the experimental farm at Nibio Ullensvang, western Norway (60°19’8.03”N; 6°39’14.31”E) in 2018. Untreated trees and trees manually thinned after June drop were used as reference treatments. Fruit set, yield data and fruit quality parameters for each treatment were recorded. None of the chemical thinning treatments resulted in a significant reduction in the final number of fruits and yield tree-1. Crop load of the untreated trees was almost twice the target crop load of the hand-thinned trees. Ammonium thiosulphate (ATS) was the only chemical thinning treatment that significantly increased fruit weight above the untreated trees, but to a lesser extent than achieved by hand thinning. Qualitative traits of ‘Rubinstep’ apples (ground and over colour, firmness, starch index and soluble solid contents were not correlated with the fruit set. Return bloom of the untreated trees was 50% of the bloom of the previous year. The ammonium thiosulphate-treated trees showed a significant higher percentage return bloom of 122%. Return bloom in all other treatments did not differ significantly from the untreated controls. However, the average values showed a clear trend of a decrease in return bloom in metamitron-treated trees in comparison with the untreated and hand-thinned trees. The exceptionally high levels of solar radiation in May 2018 and the excellent pollination conditions resulting in very high seed numbers fruit-1 are likely the reasons for the lack of thinning efficacy of Brevis®.
Authors
Fuad Gasi Oddmund Frøynes Belma Kalamujic Stroil Lejla Lasic Naris Pojskic Milica Fotiric Aksic Mekjell MelandAbstract
The diploid Celina/QTee® (‘Colorée de Juillet’ × ‘Williams’), one of the most promising pear cultivars developed by the Norwegian breeding program Graminor, was launched in 2010. In Norway, the flowering is medium to late, while the fruits ripen in the beginning of September. The fruits are attractive with an intense red blush (50%) on a green background. Although, ‘Celina’ is cultivated in the most climatically suitable regions for fruit cultivation, present in Norway, unfavorable environmental conditions for pear pollination can have a very negative effect on fruit set and consequent yield. The aim of this study was to determine the S-alleles of ‘Celina’, as well as its frequently used pollinizers, and, through paternity testing of ‘Celina’ seeds, give a recommendation regarding the most important pollinizers of this pear cultivar. In order to accomplish this, ‘Celina’ and its potential pollinizers were all S-genotyped. After harvest, seeds collected from ‘Celina’ fruit in 2017 and 2018 were genotyped using eleven microsatellite markers. Genomic DNA was also extracted from leaf material collected from ‘Celina’, as well as from five pear cultivars used as pollinizers in the three examined orchards, and analyzed using the same marker set. Subsequently a simple sequence repeat (SSR) database was constructed and used for gene assignment analyses with the aim of quantifying pollen donor contribution from individual pollinizers. The obtained results indicate that ‘Anna’, the only examined pollinizer that was fully cross-compatible with ‘Celina’, together with ‘Fritjof’, the genotype which had the highest flowering overlap with ‘Celina’, proved to be the most successful pollinizers across all seasons and orchards. Although both cultivars were ubiquitous in the examined orchards, either as planted trees or as branches introduced during the flowering period, they were the most abundant pollinizers in only one orchard each. It is therefore possible to conclude that pollinizer abundance has a secondary significance in pollinizer success within investigated ‘Celina’ orchards.
Abstract
Norwegian pear production is low due to climatic limitations, a lack of well-adapted cultivars and suitable pollinizers. However, nowadays it is increasing as a result of newly introduced and bred pear cultivars. Since cross pollination is necessary for high yields and good fruit quality, the aim of this investigation was to find the most suitable pollinizers for the pear cultivars “Ingeborg” (“Conference” × “Bonne Louise”) and “Celina” (“Colorée de Juillet” × “Williams”). Self-pollination of “Ingeborg” and “Celina”, together with “Conference”, “Belle Lucrative”, “Anna”, “Clara Frijs”, “Herzogin Elsa”, “Kristina” and “Fritjof” as potential pollinizers, were studied in this experiment during the 2017 and 2018 seasons in Norway. The success rate of each pollinizer was tested under field conditions, while the monitoring of pollen tube growth was done using the fluorescence microscopy method. All reproductive parameters (pollen germination, number of pollen tubes in the upper part of the style, pollen tube number in the locule of the ovary, number of fertilized ovules, initial fruit set, and final fruit set) in all crossing combinations were higher in 2018 due to much warmer weather. Based on the flowering overlap and success rate of each individual pollinizer and fruit set, the cultivars “Anna” and “Clara Frijs” can be suggested as pollinizers for the cultivar “Ingeborg”, while “Fritjof”, “Anna”, “Kristina” and “Herzogin Elsa” for the cultivar “Celina”. An even distribution of two compatible pollinizers having overlapping flowering times with the main commercial pear cultivar is a general recommendation for commercial pear production.
Abstract
No abstract has been registered
Abstract
No abstract has been registered
Authors
Milica Fotiric Aksic Uros Gasic Dabic Zagorac Dragana Milica Sredojevic Tomislav Tosti Maja Natic Mekjell MelandAbstract
The aim of this research was to analyze sugars and phenolics of pollen obtained from 15 different ‘Oblačinska’ sour cherry clones and to assess the chemical fingerprint of this cultivar. Carbohydrate analysis was done using high-performance anion-exchange chromatography (HPAEC) with pulsed amperometric detection (PAD), while polyphenols were analyzed by ultra-high-performance liquid chromatography–diode array detector–tandem mass spectrometry (UHPLC-DAD MS/MS) system. Glucose was the most abundant sugar, followed by fructose and sucrose. Some samples had high level of stress sugars, especially trehalose. Rutin was predominantly polyphenol in a quantity up to 181.12 mg/kg (clone III/9), with chlorogenic acid (up to 59.93 mg/kg in clone III/9) and p-coumaric acid (up to 53.99 mg/kg in clone VIII/1) coming after. According to the principal component analysis (PCA), fructose, maltose, maltotriose, sorbitol, and trehalose were the most important sugars in separating pollen samples. PCA showed splitting off clones VIII/1, IV/8, III/9, and V/P according to the quantity of phenolics and dissimilar profiles. Large differences in chemical composition of studied ‘Oblačinska sour cherry’ clone pollen were shown, proving that it is not a cultivar, but population. Finally, due to the highest level of phenolics, clones IV/8, XV/3, and VIII/1 could be singled out as a promising one for producing functional food and/or in medicinal treatments.
Authors
Milica Fotiric Akšic Dragana Dabic Zagorac Milica Sredojevic Jasminka Milivojevic Uros Gasic Mekjell Meland Maja NaticAbstract
Chemical characterizations of leaves and fruits that were obtained from organically and integrally produced strawberries (′Favette′, ′Alba′, and ′Clery′) and blueberries (′Bluecrop′, ′Duke′, and ′Nui′) from western Serbia were undertaken in this study. Phenolic analysis was done while using ultra-high performance liquid chromatography coupled to a linear ion trap-Orbitrap hybrid mass analyzer, while total phenolic content (TPC), total anthocyanin content (TAC), and radical-scavenging activity (RSA) by spectrophotometry. In general, leaves and fruits from blueberry showed higher levels of TPC and TAC as compared to strawberry. These chemical traits were larger in organic grown fruits and larger in leaves than fruits. The most abundant phenolics in leaves and fruits of blueberry was 5-O-caffeoylquinic acid, followed by quercetin 3-O-galactoside, while catechin, quercetin, and kaempferol 3-O-glucosid were dominant in the leaves and fruits of strawberry. cis, trans-Abscisic acid was detected in all fruit samples, but not in leaves. Blueberries (both fruits and leaves) were separated from strawberries, but only organic blueberry fruits were distinguished from integrated fruits, according to principal component analysis. Quercetin, kaempferol, 5-O-caffeoylquinic acid, ferulic acid, caffeic acid, catechin, p-coumaric acid, and p-hydroxybenzoic acid were the most influential phenolic compounds for the separation. Much higher contents of TPC, RSA, TAC, quercetin 3-O-galactoside, and quercetin were found in fruits and TPC, RSA, catechin, p-hydroxybenzoicacid, p-coumaricacid, and ferulic acid in leaves in all three blueberry cultivars and the strawberry cultivar ′Clery′. These phenolic compounds are good sources of antioxidant compounds with potentially high beneficial effects on human health.
Authors
Milica Fotiric Akšic Tomislav Tosti Milica Sredojevic Jasminka Milivojevic Mekjell Meland Maja NaticAbstract
The objective of this study was to determine and compare the sugar profile, distribution in fruits and leaves and sink-source relationship in three strawberry (‘Favette’, ‘Alba’ and ‘Clery’) and three blueberry cultivars (‘Bluecrop’, ‘Duke’ and ‘Nui’) grown in organic (OP) and integrated production systems (IP). Sugar analysis was done using high-performance anion-exchange chromatography (HPAEC) with pulsed amperometric detection (PAD). The results showed that monosaccharide glucose and fructose and disaccharide sucrose were the most important sugars in strawberry, while monosaccharide glucose, fructose, and galactose were the most important in blueberry. Source-sink relationship was different in strawberry compared to blueberry, having a much higher quantity of sugars in its fruits in relation to leaves. According to principal component analysis (PCA), galactose, arabinose, and melibiose were the most important sugars in separating the fruits of strawberries from blueberries, while panose, ribose, stachyose, galactose, maltose, rhamnose, and raffinose were the most important sugar component in leaves recognition. Galactitol, melibiose, and gentiobiose were the key sugars that split out strawberry fruits and leaves, while galactose, maltotriose, raffinose, fructose, and glucose divided blueberry fruits and leaves in two groups. PCA was difficult to distinguish between OP and IP, because the stress-specific responses of the studied plants were highly variable due to the different sensitivity levels and defense strategies of each cultivar, which directly affected the sugar distribution. Due to its high content of sugars, especially fructose, the strawberry cultivar ‘Clery’ and the blueberry cultivars ‘Bluecrop’ and ‘Nui’ could be singled out in this study as being the most suitable cultivars for OP.
Authors
Mekjell MelandAbstract
No abstract has been registered
Abstract
Large amounts of fruit seeds are discarded yearly in different producing industries, which is a waste of a potentially valuable resource as well as a serious disposal problem. Plum is the most important type of commercial fruit in Serbia and seeds could be obtained as a byproduct of alcoholic beverage processing. Their exploitation should be greater and more information about cultivars’ kernels and their composition is required. Also, consumers’ tendency for “natural foods” arises a need for characterization of genotypes with high phenolic contents which could be used in processed food products. Discarding large amounts of plum seeds is a waste of potentially precious sources of phytochemicals. In order to characterize the phenolic profile of approximately 30 plum cultivars, phenolic acids and flavonoids, as potential antioxidants, were determined by ultra-high-performance liquid chromatography (UHPLC) coupled with hybrid mass spectrometry, which combines the Linear Trap Quadrupole (LTQ) and OrbiTrap MS/MS mass analyzer together with chemometric analysis. The UHPLC–LTQ OrbiTrap MS technique was proven to be reliable for the unambiguous detection of phenolic acids, their derivatives, and flavonoid aglycones based on their molecular masses and fragmentation pattern. The phenolic acids prevail over the flavonoids, with protocatechuic acid, p-hydroxybenzoic acid, ferulic acid, and chlorogenic acid as the most abundant ones. In addition, catechin was the most abundant flavonoid.
Abstract
High tunnels offer an intensive and protective production system for many fruit crops. In May 2014, two tractor-accessible Haygrove® multibay tunnel systems were installed on a 10% slope at the experimental farm at Nibio Ullensvang, western Norway (60°19’8.03”N, 6°39’14.31”E). Feathered 1-year old European plum cultivar ‘Opal’ on rootstock ‘St. Julien A’ were planted with two rows per bay at a spacing of 1.5×4 m during 2012. Trees were trained to a central leader as free spindles. In 2016, one tunnel was covered (150 μm clear classic polyethylene film) from before blooming until harvest and one tunnel only covered from mid-July till harvest. Different crop loads levels were established by blossom thinning (each flower 5, 10, and 15 cm apart), and fruitlet thinning (each fruitlet 5, 10, and 15 cm apart) at 10-12 mm fruitlet diameter at the end of June. Treatments were applied on single whole trees in a randomized complete block design with five replications. Climatic parameters were monitored inside and outside the tunnels from mid-June to mid-September. Fruit set, yield data, and fruit quality parameters for each treatment were recorded. Increased thinning distances reduced the fruit set and was highest when thinned at fruitlets. Thinning to 5 cm apart and covered the whole season and 10 cm apart covered one month gave the highest fruit sets of 17.9 and 14.3%, respectively. The yield was positively correlated with the fruit set response, 11.7 kg tree-1 (20 t ha-1) – 5 cm between fruitlets and short-covering versus 3.4 kg – 15 cm distance between flowers and long covering. Both blossom and fruitlet thinned trees when covered got a significant yield reduction compared to covered one month. Thinning at the fruitlet stage resulted in smaller fruits at the same crop level (41.3 g on average) compared to flower thinning for both covering periods (47.2 g). Qualitative traits of ’Opal’ plums (bright yellow ground colour, red over colour, and soluble solid contents) were weakly correlated with the fruit set and was high (16.7% average soluble solids content). The coverage from bloom to harvest time promoted maturity of the plums. From the preliminary results, it can be concluded that fruitlets thinning from uncovered trees and one month covering before harvesting gave the largest crop of premium fruits.
Abstract
For plum production to be economically viable, dwarfing rootstocks are essential for establishing high-density orchards, which ensure easier management, lower production costs, and earlier yields. Performance of the semi-dwarfing plum rootstocks ‘Wavit’, ‘Ute’ (both clones of Prunus domestica), and the dwarfing ‘VVA-1’ (Krymsk®1) was compared against the industry standard, ‘St. Julien A’. Onto these rootstocks, scion cultivars ‘Excalibur’, ‘Reeves’, and ‘Valor’ were grafted and assessed in a replicated field trial in western Norway at 60° North. Trees were planted in spring 2006 and the ‘VVA-1’ rootstock in May 2007. Plants were all one-year-old whips, spaced 2.0×4.0 m apart and trained to a central leader as free spindles. Tree vigour, yield, fruit size, fruit quality, and yield efficiency were evaluated for eight subsequent years. Tree size was significantly influenced by the rootstock after eight years of growth. ‘VVA-1’ produced the smallest trees, about half the tree size of ‘St. Julien A’ as measured by trunk cross-sectional area. ‘Wavit’ and ‘Ute’ were similar in size to ‘St. Julien A’. All plum trees came into production slowly. On average the cultivars ‘Excalibur’ and ‘Reeves’ were harvested in mid-September and ‘Valor’ two weeks later. During the period 2011-2014, when trees were fully mature, ‘Reeves’ and ‘Valor’ grafted on the three semi-dwarfing rootstocks resulted in the highest yields tree-1. ‘VVA-1’ resulted in significantly lower yields for ‘Valor’. ‘Excalibur’ was the only cultivar in which ‘VVA-1’ significantly increased yield efficiency. Accumulated yield from 2011-2015 on ‘VVA-1’ was 0.52 kg cm-2 TCSA, 2.3 times more than on ‘St Julien A’. Fruit weight in ‘Excalibur’ and ‘Reeves’ was on average 57 and 62 g, respectively, and not affected by the different rootstocks. ‘Valor’ on ‘VVA-1’ showed a 10 g reduction in fruit weight compared to 59 g fruit weight on the other rootstocks. Fruit soluble solids were on average around 13 °Brix for ‘Excalibur’ and ‘Reeves’ and 16 °Brix for ‘Valor’ and did not differ significantly between trees on the different rootstocks tested. In conclusion, ‘St. Julien A’ was the most reliable semi-vigorous rootstock and resulted in the highest accumulated yields over the first eight years after planting and with favourable effects on fruit quality of all European plum cultivars evaluated. ‘VVA-1’ resulted in trees of low vigour which, especially with ‘Excalibur’, were more precocious and had higher yield efficiencies than all other rootstock scion combinations. If this rootstock is to be used it should be planted at a higher density per area than the semi-dwarfing rootstocks and on fertile soil with fertigation provided.
Abstract
No abstract has been registered
Abstract
No abstract has been registered
Abstract
The presence of pollinators in orchards is crucial to obtain high fruit set and yields of fruits. Despite the fact that sour cherry cultivars are mainly autogamous, insect visits are still of great importance for their propagation. In order to attract and reward pollinators, flowers have to provide adequate nourishment to them. Besides nectar, bees gather pollen, which are a prerequisite for normal colony growth and development of their broods. ‘Oblačinska’ sour cherry (Prunus cerasus L.), an autochthonous cultivar, is the most highly planted cultivar in Serbian commercial orchards. Since the cultivar is actually a mixture of different clones, variability in numerous traits and, particularly, its yields has been reported. Since phenolic compounds are considered to be fundamental pollen chemicals, the aim of this study was to determine the phenolic compounds profile in pollen collected from 15 ‘Oblačinska’ sour cherry clones with varying productivity levels. Solid phase extraction (SPE), combined with ultra-high-performance liquid chromatography coupled with a diode array detector and a triple quadruple mass spectrometer (UHPLC DAD-MS/MS), was used to analyse the polyphenolic profile of pollen. Among 23 components quantified, rutin was the most abundant phenolic compound. It ranged from 98.49 (clone V/P) to 358.83 mg kg-1 (clone III/9) and was observed to contribute, on average, 56% of the total phenolic compounds in pollen as quantified in different ‘Oblačinska’ sour cherry clones. In addition to this compound, clones contained significant amounts of chlorogenic acid (12.92%), astragalin (8.19%), and hyperoside (5.59%) as well. Cluster analysis grouped pollen clones in four different clusters, which showed that clones III/9, IV/8, and V/P had unique phenolic profiles. Despite the significant differences among the studied clones, the contents of chlorogenic acid, rutin, naringin, hyperoside, astralgin, and phlorizin were distinguishable between the clusters.
Abstract
No abstract has been registered
Abstract
No abstract has been registered
Authors
Mekjell MelandAbstract
No abstract has been registered
Authors
Mekjell MelandAbstract
Sweet cherry production worldwide is grown in the open land. Production technique is more or less similar with scions grafted on dwarfing and semi-dwarfing rootstock and trees arranged in single rows. Sweet cherries can be grown in Norway in areas with suitable local climatic conditions up to 60°N. All orchards have high density planting systems and are rain covered. Rain-induced fruit cracking in cherries remains a problem at an international level. The most common systems in Norway are multibay high tunnel systems and retractable rain covers. Covered orchard tunnel systems offer not only the advantage of rain exclusion but also allow additional manipulation of the environment, tree growth and fruiting. In general, sweet cherry high tunnel production gives increased yields of larger fruit than in the open land, but investment costs are higher. This overview article describes results from different experiments about high tunnels sweet cherry production mainly conducted at Nibio Ullensvang, Norway during the last ten years.
Abstract
Cherries (Prunus avium L. and Prunus cerasus L.) are economically important fruit species in the temperate region. Both are entomophilous fruit species, thus need pollinators to give high yields. Since cherry’s flower is easy-to-reach, bees and other pollinators can smoothly collect nectar as a reward for doing transfer of pollen to receptive stigma. Nectar in cherry is usually attractive for insects, especially to honey bee (Apis melifera) who is the most common pollinator. Nectar is predominantly an aqueous solution of sugars, proteins, and free amino acids among which sugars are the most dominant. Trace amounts of lipids, organic acids, iridoid glycosides, minerals, vitamins, alkaloids, plant hormones, non-protein amino, terpenoids, glucosinolates, and cardenolides can be found in nectar too. Cherry flower may secrete nectar for 2–4 days and, depending on the cultivar, produces up to 10 mg nectar with sugar concentration from 28% to 55%. Detailed chemical analysis of cherry nectar described in this chapter is focused on sugar and phenolic profile in sour cherry. The most abounded sugars in cherry nectar was fructose, glucose, and sucrose, while arabinose, rhamnose, maltose, isomaltose, trehalose, gentiobiose, turanose, panose, melezitose, maltotriose, isomaltotriose, as well as the sugar alcohols glycerol, erythritol, arabitol, galactitol, and mannitol are present as minor constituents. Regarding polyphenolics, rutin was the most abundant phenolic compound followed by naringenin and chrysin. Cherry cultivars showed different chemical composition of nectar which implies that its content is cultivar dependent.
Abstract
Sweet cherry production worldwide is grown in the open land. Production technique is more or less similar with scions grafted on dwarfing and semi-dwarfing rootstock and trees arranged in single rows. Sweet cherries can be grown in Norway in areas with suitable local climatic conditions up to 60°N. All orchards have high-density planting systems and are rain covered. Rain-induced fruit cracking in cherries remains a problem at an international level. The most common systems in Norway are multibay high tunnel systems and retractable rain covers. Covered orchard tunnel systems offer not only the advantage of rain exclusion but also allow additional manipulation of the environment, tree growth and fruiting. In general, sweet cherry high tunnel production gives increased yields of larger fruit than in the open land, but investment costs are higher. One more advanced way of producing sweet cherries is to grow the trees in small pots in greenhouses. A greenhouse gives opportunity to control the temperature regime and in that way program the maturity of the fruits. Research is conducted to test different cultivars, rootstocks, training methods in high-density production systems (1 tree m-2) with different fertigation levels. Preliminary results show that the yield potential is much higher than in the open land with larger fruits. Challenges are to optimize the water and nutrition supply and adjust the temperatures to obtain large yields of high quality fruits during different periods of the season.
Abstract
No abstract has been registered
Abstract
No abstract has been registered
Abstract
No abstract has been registered
Abstract
No abstract has been registered
Abstract
No abstract has been registered
Abstract
European plums (Prunus domestica L.) blossom abundantly most years and often set too many flowers. If these excessive numbers of fruitlets remain on the trees until harvest, the crop would consist of small, unmarketable fruits of low fruit quality. Thinning agents like ammoniumthiosulphate (ATS), sulphur and soya oil desiccate flowers, especially stigma, which is the most sensitive tissue part of the flower. This way, the main effect of blossom thinning treatments is the disruption of pollination and fertilization. Thinning trials were conducted at a commercial orchard near the shore of the Hardangerfjord near Nibio Ullensvang, western Norway (60.2°N) on mature ‘Jubileum’ trees, all grafted on ‘St. Julien A’ rootstock. The trees were treated with 0.4, 0.8, 2 and 4% sulphur; a mixture of 0.4% sulphur + 2% soya oil and 1.5% ATS (liquid and powder formulations), at full bloom. All treatments were compared with hand-thinned and unthinned trees which were used as a control. Experimental trees were sprayed to the point of run-off with a hand sprayer during May 2008 and 2009 at full bloom. Flower thinners were efficient at relatively low temperatures which is a benefit in a cooler climate. In 2008 all thinning treatments reduced fruit set compared to unthinned controls for all cultivars. Sulphur and soya oil, both alone and in combination, were significantly less effective than ATS. In 2009, fruit set was higher and the effects of all thinning agents were lower. Fruit set decreased with increasing sulphur concentrations, but fruit thinning was not sufficient, even at the highest concentration. Both the liquid and powder formulations of ATS gave the same thinning effects. For all thinning treatments, both significant yield reductions and fruit weight increment were noticed during the experimental period. Fruit over color and soluble solids were generally higher and increased significantly with lower crop load, while fruit firmness (Durofel) and total acidity were less affected. In conclusion, different concentrations of sulphur had a moderate thinning effect and are not recommended for use as plum thinners under these conditions. Instead, 1.5% ATS application, (liquid and powder) applied at full bloom, resulted in adequate thinning of ’Jubileum’ plums under cool mesic northern climatic conditions.
Authors
Mekjell MelandAbstract
No abstract has been registered
Abstract
No abstract has been registered
Abstract
No abstract has been registered
Abstract
Due to their Mendelian inheritance, microsatellites or SSRs (simple sequence repeats) can readily be used for parentage analyses of pear seedlings, thus revealing the female and male parents of the plant. However, in cases where obtained pear seeds display low viability, conducting a parentage analyses on the pear seeds themselves could be used in order to identify the male parent (successful pollinator). In this study, batches of seeds were extracted from fruits of the triploid ‘Ingeborg’ pear (‘Conference’ × ‘Bonne Louise’), the main commercial pear cultivar in Norway. Mature pears were collected from eight commercial pear orchards located in Ullensvang, at 60° North and seeds were collected. Genomic DNA was subsequently isolated from the obtained seed batches and genotyped using 12 microsatellite markers. The same markers were also used for the genetic characterization of ‘Ingeborg’ and five pear genotypes used as pollinators in the sampled orchards (‘Clara Frijs’, ‘Herzogine Elsa’, ‘Anna’, ‘Colorée de Juillet’ and ‘Belle lucrative’). The obtained SSR profiles were used in paternity analyses, as well as for gene assignment analyses. Both approaches identified pear ‘Clara Frijs’ to be the most successful pollinator in most of the sampled orchards. Subsequent S allele genotyping of ‘Ingeborg’ and five pear genotypes used as pollinators in the sampled orchards revealed that the preferential pollination by individual genotypes was not caused by gametophytic incompatibility or semi-compatibility.
Authors
Milica Fotiric-Aksic U Gasic T Tosti Jasminka Milivojevic Vlado Licina Z Tesic Mekjell MelandAbstract
No abstract has been registered
Abstract
No abstract has been registered
Abstract
The Norwegian newly bred pear cultivar, Celina/QTee®, which was launched in 2010, has been released from the Norwegian breeding program that was initiated in 1983. It was derived from the combination ‘Colorée de Juillet’ × ‘Williams’. In Norway the flowering is medium to late and it ripens in the beginning of September. It has large attractive fruits with a red blush. It has a good fruit quality, storability and shelf life. Cross pollination is necessary in order to have high yields of this diploid cultivar. Pollination of ‘Celina’ with pollen of four donors (‘Conference’, ‘Kristina’, ‘Anna’ and ‘Fritjof’), together with open- and self-pollination were studied in this experiment during the 2016 season in Norway. The dynamics of the pollen tube growth (third, sixth and ninth day after anthesis) in style (upper, middle and lower third) and parts of the ovary in all crossing combination, were observed by fluorescent microscopy. Besides giving the best results regarding the average number of pollen tubes in different parts of pistils and the dynamics of pollen tube growth, ‘Conference’ was the only one of which the pollen tubes didn’t show any incompatible signs while growing through the transmitting tissue of the ‘Celina’ style. According to those preliminary results, ‘Conference’ was the best pollenizer, followed by ‘Kristina’. The study has to be repeated for another season.
Authors
Adnan Alihodzic Fuad Gasi Pakeza Drkenda Asima Akagic Amila Vranac Mekjell Meland Osman Music Nermina SpahoAbstract
Introduction and background: Autochthonous fruits in Bosnia and Herzegovina (B&H) represent great opportunities for fruit breeding, because they could be grown without costly agricultural inputs and offer valuable assets for the fruit processing industry providing a specific and different sensory taste for the fruit products. Hence, the objective of this study was to sensory evaluate fruits from 34 autochthonous apple and 29 pear cultivars in 2012 and 2013 from an ex-situ collection in B&H by eight trained panelists, using Quantitative Descriptive Analysis (QDA). Experimental: Flavour of fruits was described by the eight sensory attributes a) flavour: odour intensity, b) sweet, c) sour, d) green, fruit, e) floral flavour, f) typically, g) after taste and h) overall conception and subjected to principal component analysis (PCA) to visualise the sensory attributes. Results: For apple, the traditional cvs. ‘Prijedorska Zelenika’, ‘Paradija’, ‘Srebrenička’, ‘Bukovija’ and ‘Ljepocvijetka’ reached the best flavour scores in both years, while in pear, cvs. ‘Takiša’, ‘Hambarka’, ‘Dolokrahan’ and ‘Kačmorka’ exhibited the best flavour in both years, followed by cvs. ‘Begarika’, ‘Jeribasma’, ‘Ahmetova’ and ‘Hambarka’ with intense floral flavour and odour. In these tastings, B & H grown apple cv. ‘Golden Delicious’ also scored highly compared with cvs ‘Idared’, ‘Granny Smith’ and ‘Gala’ with a lesser characteristic apple flavour and pear cvs ‘Williams’ and ‘Sweet Harrow’ scored better than ‘Alexander Lukas’ and ‘Gellerts’ from B & H.
Abstract
No abstract has been registered
Abstract
No abstract has been registered
Abstract
No abstract has been registered
Abstract
No abstract has been registered
Abstract
No abstract has been registered
Authors
Mekjell MelandAbstract
No abstract has been registered
Abstract
Tunnel production of sweet cherry results in higher yields of larger fruit than in the open. When cherry trees were grown under tunnels in Norway, fruit cracking was higher in a year when soils were saturated and when 20 ppm gibberellic acid was applied at straw color. In this study we evaluated the effect of soil moisture on fruit cracking under tunnels. In 2013, a trial on mature 'Sweetheart'/'Colt' trees growing under high tunnels was initiated. Each plot consisted of 8 trees, spaced 2×4 m apart with 'Lapins' as guard trees. Experimental design was a split-plot design with or without 20 ppm GA3 application at straw color; and three drip irrigation regimes (zero, deficit and full based on evapotranspiration). During the season, soil water content was monitored weekly. Due to unfavorable weather conditions during bloom time, crop loads were lower than normal. Average fruit sizes were large and GA3 application at yellow straw color resulted in small increases in average fruit diameter and fruit weight with all three irrigation treatments. Fruit cracking was very variable and occurred almost exclusively at the distal side of fruit and not on the stem side. GA3-treated fruit cracked slightly more than untreated fruit. There were no differences in fruit cracking due to irrigation scheme.
Abstract
Flowering is one of the most important factors in plant fertility. Fruit set in fruits is directly influenced by the beginning, sequence, flow, duration and abundance of flowering. The objective of this study was to evaluate the variability of flowering in 41 ‘Oblačinska’ sour cherry (Prunus cerasus L.) clones, and to recommend earlyflowering genotypes for growing in warmer locations where late spring frosts are rare, and some late-flowering clones for sites more susceptible for spring frost. Results from the three years period (2004-06), showed that ‘Oblačinska’ sour cherry clones flowered in a fixed sequence each year. Average for clone VII/2N, which flowered the earliest, was April 8 and petal fall took place by April 21, whereas clone III/1 bloomed last on April 14 and petal fall took place on April 25. Statistical analysis showed that almost all sub-phases of flowering were under the significant influence of both ecological and genetic factors. Besides, ecologic factors had the highest impact to the variability of beginning of flowering (79.8%), full bloom (76.8%), petal fall (80.2%) and duration of flowering (85.56%). Clones III/1, III/13, V/6 and V/2 were considered as late flowering, whereas clones VII/2N, VI/27, VI/28 and IX/P were early flowering, taking place five days earlier then previous group.
Authors
Kenan Kanlic Belma Kalamujic Naris Pojskic Jasmin Grahic Fuad Gasi Åsmund Asdal Mekjell MelandAbstract
In order to investigate the genetic structure and differentiation among north and south European apple germplasm, 141 apple accessions maintained in ex situ collections in Norway and 110 traditional and international apple accessions from Bosnia and Herzegovina (B&H) were analyzed using 8 microsatellite markers. Bayesian analyses, based on the microsatellite data, grouped most of the accessions into two major clusters. The first cluster consisted mainly of traditional and international B&H accessions, as well as Norwegian accessions derived mostly from foreign or formal breeding programs (‘James Grieve’, ‘Katja’, ‘Summerred’, ‘Bramleys Seedling’, ‘Elstar’, ‘Katinka’, ‘Belle de Boskoop’, ‘Jacques Lebel’, etc.). The second cluster consisted almost exclusively of traditional Norwegian accessions. Further analyses divided each cluster into two sub-clusters. Cluster 1.1 included Norwegian accessions derived from foreign or commercial breeding programs, international cultivars and B&H accessions introduced from Europe and North America during the rule of Austria-Hungarian Empire. Cluster 1.2 included traditional B&H accessions introduced during the reign of Ottoman Empire. Cluster 2.1 and 2.2 consisted mainly of traditional apple accession from Norway. The results obtained indicate a clear genetic structure and differentiation among north and south European apple germplasm, presumably due to climate adaptation and selection.
Abstract
Perennial fruit crops phenology such as cherry is an ideal bio-indicator of climate change due to their long-lasting features, in particular, dates of flower opening and full bloom. This implies i) the use of several generations of cherry trees/orchards and ii) the use of the same original cherry cultivars, which existed as bearing trees and were replanted after the orchard had been grubbed. A comparison of available definitions of phenological stages in cherry previously used independently throughout Europe showed overlaps and shortcomings; hence, harmonisation was reached in this respect in the COST Cherry FA 1104 working group 2 (cherry phenology and climate change) based largely on the acceptance of the BBCH scale. This contribution presents the agreed phenology stages in both visual and wording evidence. Similarly, this contribution presents the agreed cultivars to be monitored in future for phenology and climate change effects for harmonisation. For sweet cherry, this EU-wide harmonisation includes ‘Burlat’, ‘Cristobalina’ and ‘Rita’ as early, ‘Stella’ and ‘Van’ as medium flowering and ‘Sweetheart’, ‘Regina’ and ‘Bigarreau Noire de Meched/Germersdorfer’ for late flowering cultivars for climate change effects. For sour cherry, this harmonisation resulted in ‘Meteor korai’ and ‘Anglaise Hative’ for early flowering, ‘Chrisana Pandy’ and ‘Erdibotermo’ for medium flowering and ‘Schattemorelle’, ‘Iiva, Ujfehrtoifurtos (Balaton)’ for late flowering.
Abstract
Intensive sweet cherry production in tunnel covered orchard systems offer an advantage of reducing rain-induced fruit cracking. In May 2005 four Haygrove multibay tunnel systems were installed on a gentle slope at the experimental farm at Bioforsk Ullensvang, western Norway. In these tunnels, feathered 1-year-old sweet cherry ‘Sweetheart’/Colt trees were planted with two rows at a spacing of 2×4 m in each tunnel. Each tunnel was split into two halves and covered from the end of April to beginning of September with one of two different plastic covers, having different light spectral transmittance; Luminance THB film (absorbing infrared light) and traditional Visqueen clear UV polythene film. Climatic parameters were monitored inside and outside the tunnels from the beginning of May to the beginning of September each year and yield data and fruit quality parameters were recorded. In 2009, from May 7 to September 16 the average temperature measured outside the tunnels was 14.3°C. Temperatures exceed 25°C only on two days. Temperatures inside the tunnels were 0.3°C higher on average during the entire season but exceeded 30°C on the same two hot days. Temperatures under the Luminance film were slightly lower compared to the clear film and especially reduced the temperature build up on sunny days. The harvest period was the second half of August. Average yield tree-1 was 8.8 kg (11 t ha-1) in the fourth leaf and 18.8 kg (23.5 t ha-1) fifth leaf. There were no yield differences between the two different films. Fruit size measurements found that 80% of the fruits were larger than 30 mm in diameter in the fourth leaf and 51% in the fifth leaf. Total soluble solid content was generally high (17-18%) and no significant differences were found between the different films.
Abstract
No abstract has been registered
Abstract
Phenological observations are considered to be sensitive tools for identifying plant responses to climatic changes. Over the last 10 years, the onset of the phenophases of sweet cherry (Prunus avium L.) during spring tended to be earlier than the previous two decades in Ullensvang, western Norway. The effects of air temperature during the winter and spring months were evaluated during two quinquennia (5-year periods), 1996-2000 (Q1) and 2003-2007 (Q2) selected due to similar mean winter and early summer temperatures, but markedly different spring temperatures. Average January-February temperatures were similar (3.3°C) in both of these two 5-year periods. However, average March and April temperatures were slightly warmer (4.0 vs. 3.2°C) and (7.3 vs. 6.9°C), respectively, in Q2 vs. Q1. These increases resulted in significantly earlier flower development. Average temperatures during the first half of May were similar for both quinquennia (10.2 vs. 10.1°C). The start of flowering (first bloom) of early maturing ‘Burlat’ and mid-season ‘Van’ were significantly different. Timing of flowering phenophases were statistically different between Q1 and Q2 for both cultivars. Mean data for ‘Burlat’ and ‘Van’ first bloom were 8 days earlier during Q2, May 2 for ‘Burlat’ and May 1 for ‘Van’. Full bloom occurred 3 days after first bloom and flowering ended 14 days after first bloom. First bloom during Q2 required 221 Baskerville-Emin Growing degree days (GDD) using a base temperature of 2°C. For the same time period in Q1, only 197 GDD were accumulated, which supports the observed temperature differences. Furthermore, we propose a flowering model for full bloom of both ‘Burlat’ and ‘Van’ in Ullensvang, which requires 254 Baskerville-Emin GDD using a base of 2°C starting on March 1.
Abstract
No abstract has been registered
Authors
Milica Fotiric-Aksic Slavica Colic D Radivojevic L Lankovic Vera Rakonjac I Bakic Mekjell MelandAbstract
No abstract has been registered
Abstract
No abstract has been registered
Abstract
No abstract has been registered
Abstract
No abstract has been registered
Authors
Fuad Gasi Naris Pojskic Mirsad Kurtovic Clive Kaiser Stein Harald Hjeltnes Milica Fotiric-Aksic Mekjell MelandAbstract
No abstract has been registered
Abstract
No abstract has been registered
Abstract
No abstract has been registered
Abstract
No abstract has been registered
Abstract
No abstract has been registered
Abstract
No abstract has been registered
Abstract
Vitality of pollen, in vitro pollen germination and pollen tube growth (pollen tube length and pollen tube growth rate) were investigated in Oblačinska sour cherry in order to determine the differences between clones which have divergent yielding potential. For this purpose two ‘Oblačinska’ sour cherry clones with high fruit set and high yields (II/2, III/9) and two with low fruit set and low-yielding (XI/3 and XIII/1) were used in this study. Pollen germination was done on artificial medium containing 14% sucrose and 0.3% agar-agar at room temperature (23°C). Pollen tube growth was stopped with a drop of 40% formaldehyde, 1, 3, 6, 12 and 24 h after contact with the medium. The maximum percentage of germination ranged from 13.01% (clone II/2, after 1 h) to 54.19% (clone III/9, after 24 h). Pollen tube length varied from 64.84 μm (clone XIII/1, after 1 h) to >1,100 μm (clones II/2 and III/9, after 24 h). Pollen growth rate was quite high (up to 1.71 μm min-1) after 6 h of germination, but rather decreasing until 24 h of germination (0.560.83 μm min-1). The dynamics of in vitro pollen tubes growth among the clones were quite different, especially after 12 h and 24 h of germination. Clones that are singled out as fruitful (II/2 and III/9) gave much better results regarding pollen germination and pollen tube growth in comparison to clones which were characterized by low fruit set and yields (XI/3 and XIII/1).
Authors
Bénédicte Wenden José Antonio Campoy Julien Lecourt Gregorio López Ortega Michael Blanke Sanja Radičević Elisabeth Schüller Andreas Spornberger Danilo Christen Hugo Magein Daniela Giovannini Carlos Campillo Svetoslav Malchev José Miguel Peris Mekjell Meland Rolf Stehr Gerard Charlot José Quero-GarcíaAbstract
Professional and scientific networks built around the production of sweet cherry (Prunus avium L.) led to the collection of phenology data for a wide range of cultivars grown in experimental sites characterized by highly contrasted climatic conditions. We present a dataset of flowering and maturity dates, recorded each year for one tree when available, or the average of several trees for each cultivar, over a period of 37 years (1978–2015). Such a dataset is extremely valuable for characterizing the phenological response to climate change, and the plasticity of the different cultivars’ behaviour under different environmental conditions. In addition, this dataset will support the development of predictive models for sweet cherry phenology exploitable at the continental scale, and will help anticipate breeding strategies in order to maintain and improve sweet cherry production in Europe.
Abstract
The European plum cultivar 'Opal', widely grown in Scandinavia, frequently initiates too many flowers and set too many fruits. If excess fruitlets remain on the trees until harvest, the crop consists of small, unmarketable fruits of low fruit quality and return bloom will be reduced. The current study investigated effects of different crop loads established at blossom and fruitlet stages on yield, fruit quality and return bloom. For two seasons starting in 2008 on mature 'Opal'/'St. Julien A' trees, two crop loads 50 and 25% flowers reduced were established at full bloom and at 10-12 mm fruitlet size and compared with an un-thinned control treatment. Treatments were applied on single whole trees in a randomized complete block design with six replications. Spindle trees spaced at 3.0×5.0 m were selected for uniformity in growth habit, flowering intensity and trunk cross sectional area. Final fruit set varied from 63% on the control trees to 18% when thinned at bloom. Yield was negatively correlated with the fruit set response. Thinning at the fruitlet stage resulted in smaller fruits at the same crop level compared to flower thinning. Fruit quality parameters characterized by bright yellow skin background colour, red surface colour and the concentrations of soluble solids increased significantly as the crop load was reduced. Other fruit quality parameters like percentage acidity were not significantly different and did not show a clear response to the thinning. Return bloom was promoted most when trees were thinned at bloom the year before.
Abstract
European plum cultivar Jubileum (Prunus domestica L.) blooms abundantly most years and too many fruit can be set if flowers and/or fruitlets are not properly thinned. In 2007, 2008 and 2009, mature ‘Jubileum/St. Julien A’ trees were treated with ethephon either at full bloom, at concentrations of 250, 375 and 500 mg/l or when fruitlets averaged ~12 mm in diameter at concentrations of 125, 250 and 375 mg/l. In general, flower-thinning treatments reduced fruit set significantly. Fruit set decreased with increasing ethephon concentrations, and the highest rate of ethephon applied either at full bloom (500 mg/l) or post bloom (375 mg/l) resulted in excessive over-thinning. Up to 375 mg/l of ethephon was required at full bloom whereas only 125 mg/l of ethephon was required post bloom for marked fruitlet thinning. Yields confirmed the fruit set response and yield reductions were significant. In most years, all thinning treatments resulted in fruit larger than 38 mm in diameter compared to fruit from unthinned control trees. Fruit quality, characterized by blue surface color and soluble solids content was generally higher and increased significantly with the reduction in crop load. Fruit firmness of fruit from all ethephon applications was lower than that of the fruit from unthinned control trees. In contrast, titratable acidity did not show a clear response to ethephon thinning. Return bloom the following year was mostly unaffected by all ethephon applications compared to the control. In conclusion, an ethephon application at a rate of up to 375 mg/l applied at full bloom will result in adequate thinning of ‘Jubileum’ plums and achieved a target of about 10- 15 % reduction in fruit set. When weather conditions are not conducive during flowering, a post bloom ethephon application at 125 mg/l may be applied however, this should only be considered in years of excessive flowering and as a last resort.
Abstract
When establishing an apple orchard it is important to stimulate the growth of young trees to fill up their allotted space in the row and minimize the time to come into full production with high quality fruit. In May 2012 two-year-old 'Summerred'/'M.9' knip trees were planted at the experimental farm at NIBIO Ullensvang, western Norway. The planting distance was 4×1 m (2500 trees ha-1). Three fertigation schemes were established (zero; low - 0.15 g N m-1 row day-1, and high nitrogen - 0.30 g N m-1 row day-1) and two crop loads allowed (low and high). In the year after planting the crop loads were limited to zero and five apples tree-1, respectively. In the third leaf the crop loads were adjusted by hand to 15 apples and 30 apples tree-1, respectively. The experimental design was a randomized blocks with four replications and 10 trees treatment-1. No significant effects of N-fertigation on soil NO3-, NH4+ or N-min contents were found. However, N-fertigation increased the leaf nitrogen content the whole season and leaf N were ≥ than the standard adequacy range (1.5-2.0%). Trees reached the desirable height of 3 m in the third leaf. Trunk circumference and number of branches per tree increased from second to third leaf, but were not significantly influenced by the N-fertigation. In the third leaf the high crop load trees yielded 7 kg tree-1 (17.5 t ha-1) and the low crop load 4 kg tree-1. Fruit weights were negatively correlated with the crop loads. Small differences in fruit quality attributes were found. Return bloom was not affected after the second leaf. However, the high crop load in the third leaf clearly reduced the amounts of return bloom in 2015, irrespective of the amount of N-fertigation.
Abstract
Prohexadione-Ca, an acylcylohexadione, is a plant growth retardant jointly developed by BASF, Germany and Kumiai Chemical Industry, Japan. In 2012, a trial on 11-year-old 'Aroma'/'M 9' apple trees growing on the experimental farm at NIBIO Ullensvang, western Norway was initiated. Trees were treated with prohexadione-Ca (trade name Regalis®, 10% prohexadione-Ca as active ingredient) 10 days after full bloom (June 6) at concentrations of 125 or 250 g ha-1; other trees were also sprayed 10 days after full bloom and again one month later (July 5) at the same concentrations and compared against an untreated control. Treatments were applied to individual whole trees in a randomized complete block design with four replications. Prohexadione-Ca treatments significantly reduced shoot growth of treated apple trees. Two treatments with 125 g or one treatment of 250 g reduced growth by ~80%. Prohexadione-Ca had little effect on yield and fruit quality. Shoot growth was also retarded in the year following application and this is attributed to a carry over effect of the prohexadione-Ca application(s).
Authors
Kenan Kanlic Belma Kalamujic Jasmin Grahic Åsmund Asdal Mekjell Meland Mirsad Kurtovic Fuad GasiAbstract
Triploid apple cultivars are often favored by human selection due to their increased fruit size, even though they possess higher requirements in terms of pollination compared to their diploid counterparts. However, similar to the sensory characteristics, preferences for the size and shape of apple fruit are not universal, but culturally dependent. In order to investigate the influence of selection pressure on the frequency of triploid genotypes among different traditional apple germplasms, 141 apple accessions maintained in ex situ collections in Norway and 115 traditional and international apple accessions from Bosnia and Herzegovina (B&H) were analyzed using 8 microsatellite markers. Genotypes possessing more than two alleles per locus were deemed to be triploid. The results of SSR analyses from this and comparable studies indicate that the triploid apple cultivars are much more frequent among the traditional apple germplasm from Southern Europe than they are among the traditional apple germplasm from Northern Europe. The possible causes for these results are also discussed.
Authors
Fuad Gasi Kenan Kanlic Belma Kalamujic Stroil Naris Pojskic Åsmund Asdal Morten Rasmussen Clive Kaiser Mekjell MelandAbstract
Apple genetic resources in Norway are currently conserved within a number of local clonal archives. However, during establishment of these ex situ collections, primary focus was not on capturing as much of the diversity as possible, but instead on preserving cultivars of particular importance to specific fruit-growing areas. To identify redun- dancies within the collection as well as to assess the genetic diversity and structure of apple germplasm currently being conserved in Norway, eight microsatellites were used in genetic characterization of 181 apple accessions. Overall, 14 cases of synonym or possibly mislabeled accessions were identified, as well as several homonyms and duplicates within and among the analyzed collections. The information obtained should contribute to overall better management of the preserved germplasm. Bayesian analysis of genetic structure revealed two major clusters, one containing most of the foreign cultivars, while the other consisted mainly of traditional Scandinavian cultivars, but also some very winter-hardy genotypes such as ‘Charlamovsky’, ‘Gravenstein’, ‘Transparente Blanche’, and ‘Wealthy’. Analyses of molecular variance (AMOVA) detected a signifi- cant genetic differentiation among the clusters ( fCT = 0.077; P < 0.01). The results of the Bayesian analyses do not indicate a strong differentiation between the foreign and the Norwegian apple accessions, however, they do suggest that climate adaptation has had a significant influence on the genetic structure of the preserved germplasm. Overall, apple accessions currently maintained ex situ in Norway represent a diverse germplasm which could be very valuable in future breeding programs, especially for the Scandinavian climate.
Abstract
No abstract has been registered
Abstract
The response of three-year-old 'Summerred' trees to crop load regulation by the chemical thinning agent Brevis® was tested in comparison with different levels of hand thinning. Brevis® was applied once or twice at a dosage of 1.1 and 2.2 kg ha-1 when fruitlets were approximately 15 and 19 mm in diameter at the time of the first and second application, respectively. All Brevis® applications significantly reduced the number of fruits tree-1. Both the single application of 2.2 kg ha-1 and the two-fold application of 1.1 kg ha-1 thinned the tree to the target crop load level of 30 apples tree-1. The degree of thinning by the single application of 1.1 kg ha-1 Brevis® did not significantly increase fruit weight and resulted in a very strong inhibition of return bloom similar to that observed in the untreated controls and trees hand thinned to 60 fruits tree-1. Return bloom was positively related to the level of thinning obtained. At the target fruit load of about 30 apples tree-1, return bloom was around 40% of the bloom in the year of the thinning trial. A further thinning to circa 15 fruits tree-1 increased return bloom to approximately 60%. In conclusion, 'Summerred' trees planted as two-year-old feathered trees should not bear more than 20 to 25 fruits tree-1 in their 3rd leaf in a northern climate to avoid the onset of biennial bearing and to ensure regular annual yields. Only then sufficient numbers of flower buds will develop to have the chance to obtain a good crop in the next year.
Abstract
No abstract has been registered
Abstract
No abstract has been registered
Abstract
No abstract has been registered
Abstract
No abstract has been registered
Abstract
No abstract has been registered
Abstract
No abstract has been registered
Abstract
No abstract has been registered
Abstract
No abstract has been registered
Authors
Asima Akagic Nermina Spaho Fuad Gasi Pakeza Drkenda Amila Vranac Mekjell Meland Besim SalkicAbstract
No abstract has been registered
Authors
Fuad Gasi Mirsad Kurtovic Belma Kalamujic Naris Pojskic Jasmin Grahic Clive Kaiser Mekjell MelandAbstract
No abstract has been registered
Abstract
No abstract has been registered
Abstract
Crop load adjustments in European plum trees (Prunus domestica L.) require thinning either by hand (mechanical) or chemical means to achieve marketable size, fruit quality and to overcome alternate bearing. Efficient tools for crop load management are highly desirable, since only a few chemical thinners are registered and hand thinning is labor intensive and costly. Gibberellic acid (GA3) was tested as a novel approach to regulate the crop load of the plum cultivar ‛Opal’ at Ullensvang, western Norway. The objective was to reduce flower bud induction in the “off-year” thus adjusting crop load the subsequent year. In 2008, an “off-year”, GA3 was applied to 9 year-old ‘Opal’ trees as a high volume spray to the point of run-off at 50 ppm or 100 ppm at either 5 weeks after full bloom or 10 weeks after full bloom, or on both dates and compared with untreated control trees. Trees were unthinned the first year but then thinned to commercial standard the following year. In the year of application, total yield was recorded and fruit quality evaluated. Return bloom, fruit set, yield and fruit quality were assessed the subsequent year. In general, there were no significant differences in crop load of all treated trees compared to untreated trees in the year of application (non-target crop) however, fruit weight increased slightly on those trees when GA3 was applied 5 weeks after full bloom compared to all other treatments and untreated trees. The following year (target crop) fruit set was significantly reduced for all GA3 treatments. The most effective application time was 5 weeks after full bloom. Before thinning, initial fruit set was greatest on untreated trees as well as on those trees treated with GA3 10 weeks after full bloom. Fruit weight and fruit colour were significantly better on trees with the least fruit set. GA3 applications had no effect on fruit firmness. It is concluded that GA3 is an effective tool for inhibiting flower bud induction in an “off-year” thus enabling crop load management the subsequent “on-year”.
Abstract
No abstract has been registered
Authors
Mekjell MelandAbstract
No abstract has been registered
Abstract
‘Summerred" apples (Malus domestica) Borkh are highly susceptible to biennial bearing if not properly thinned. This results in erratic yields and also affects fruit quality adversely. Between 2003 and 2005 ‘Summered"/‘M9" trees were treated with ethephon at concentrations of 250, 375 and 500 mL·L-1 when most king flowers opened (ca. 20% bloom) or at concentrations of 500, 625 and 750 mL·L-1 when the average fruitlet size was 10 mm in diameter. The experimental design was a completely randomised block design with 6 whole tree plots per replication. Trees were sprayed to the point of run-off with a hand applicator only when temperatures exceeded 15ºC. Within two weeks after the second application fruit set was reduced linearly with increasing concentrations of ethephon to less than 1 fruitlet per cluster at the highest concentrations used. Most thinning treatments reduced fruit set significantly compared to unthinned trees. Fruit numbers per tree decreased significantly with increasing ethephon concentrations, and the highest concentrations of ethephon applied during bloom or when the average fruitlet size was 10 mm in diameter resulted in over-thinning. Yield results confirmed the fruit set response where yield reductions were significant at highest concentrations of ethephon (2.1 kg·tree-1) compared to hand-thinned trees (7.3 kg·tree-1) in 2005. All thinning treatments resulted in higher percentage of fruits larger than 60 mm diameter average fruit size compared to unthinned control fruit. Thinning resulted in significantly higher soluble solid contents, and this was especially so for hand-thinned trees. Other fruit quality parameters like yellow/green background color did not show a clear response to thinning. Fruit firmness, however, decreased slightly in all ethephon treated trees whereas return bloom was improved on all thinned trees. It is recommended that ethephon be applied at a rate of 375 mL·L-1 when king flowers open or at a rate of 625 mL·L-1 when the average fruitlet size is 10 mm in diameter. These treatments thin ‘Summerred" apples to a target of about 5 fruits·cm-2 per trunk cross sectional area or 50-70 fruits·100 flower clusters-1 without impacting fruit quality, yield or return bloom the following year.
Authors
Clive Kaiser Philip B. Hamm Stacy Gieck Nicholas David Lynn Long Mekjell Meland J. Mark ChristensenAbstract
In vitro dose responses of several calcium and potassium salts were determined on some commercially significant plant pathogens including: Helminthosporium solani, Fusarium oxysporum f. sp. pisi race 2, Colletotricum coccodes, Phytophthora cactorum, Phytophthora cinnamomi, Phytophthora erythroseptica, Phytophthora infestans, Phytophthora megasperma, Pythium ultimum and Venturia inaequalis. Mycelial growth inhibition was both salt-specific and dose-related. Pythium ultimum was completely inhibited by ≥75 mg·L-1 calcium propionate, but needed ≥ 300 mg·L-1 of calcium acetate and ≥ 40 mL·L -1 of potassium silicate for complete inhibition. Phytophthora infestans was completely inhibited by ≥150 mg·L-1 calcium acetate, ≥150 mg·L-1 calcium propionate or ≥ 5 mL·L-1 potassium silicate. Phytophthora cactorum was completely inhibited by ≥ 300 mg·L-1 calcium propionate, but required ≥ 600 mg·L-1 calcium acetate and ≥10 mL·L-1 potassium silicate for complete inhibition. Phytophthora cinnamomi was completely inhibited by calcium propionate at ≥ 600 mg·L-1, or by ≥10 mL·L-1 potassium silicate. Only potassium silicate inhibited Phytophthora megasperma, Phytophthora erthroseptica, V. inequalis and H. solani at concentrations of ≥ 5mL·L-1, ≥ 20 mL·L-1, ≥ 40 mL·L-1 or ≥ 80mL·L-1 respectively. Potassium acetate did not completely inhibit any of the pathogens in this study when tested at concentrations ≤ 1200 mg·L-1.
Abstract
No abstract has been registered
Authors
Mekjell MelandAbstract
No abstract has been registered
Abstract
This paper describes briefly the phenomena of alternate bearing of European plums and point out that more detailed investigations about physiological factors, in particular plant hormones, involved in the flowering process are of great importance.
Abstract
Fruit samples of seven sweet cherry cultivars grouped into three different groups of fruit flesh firmness (soft-fruited: 'Ranna Ljaskovska', 'Vista' and 'Sunburst', medium firm: 'Ulster' and 'Sylvia' and firm cultivars: 'Van' and 'Lapins') were harvested over a three week period with 3-4 d intervals prior to, during and after normal harvest time in 1997 and 1998 in Ullensvang, western Norway. Fruit firmness was measured at each harvest date along with measurements of soluble solids content (SSC), air temperature, precipitation and estimation of fruit colour. Corresponding samples picked at normal harvest date were stored in normal air atmosphere at temperatures 2 degrees C and 8 degrees C, respectively, and firmness was measured during storage with 3-5 d intervals. All the tested cultivars reached normal firmness, colour and SSC at harvest both years. Fruit were generally darker in 1998 than in 1997. All cultivars showed a more or less distinct reduction in firmness over the period prior to and slightly after normal harvest. Exceptions were 'Sunburst' in the 1998-season, that increased in firmness after normal harvest date, and the two firmest cultivars that increased in firmness over the ripening period in 1997. Generally, firmness increased during the first part of storage followed by a decrease after 1-2 weeks, the decrease being usually earlier and more distinct at 8 degrees C than at 2 degrees C. 'Van' in 1998 showed no change in firmness development throughout the storage period but a small increase in the last part. 'Lapins' in 1997 had however, a pronounced drop in firmness in the middle of the storage period followed by an increase. All the tested cultivars were more firm at normal harvest time in 1998 than in 1997, except the two firm-fleshed cultivars 'Van' and 'Lapins'. The warm and sunny 1997-summer produced softer fruits than the cold and rainy 1998-season, except for the firm-fleshed cultivars. It was anticipated that the many contradictory results of sweet cherry fruit firmness reported by other authors may be caused by differences in weather conditions as demonstrated.
Authors
Mekjell MelandAbstract
‘Elstar" is the latest-maturing commercial apple cultivar grown in Norway, with high fruit quality when properly managed. In May 2006, an experiment with four different crop loads [2, 4 ,6, or 8 flowers or fruitlets cm-2 trunk crosssectional area (TCSA), respectively] was established at two different stages [first bloom (FB), or 20-mm diameter fruitlets] and compared to unthinned control trees. Fruit growth was measured on individual fruit for each treatment throughout the season at weekly intervals. Thinning at FB gave a significantly lower final percentage fruit set than thinning to the same cropping level at the 20-mm fruitlet stage. However, fruit weights and soluble solids contents (SSC) were significantly higher, and the background fruit colour improved when trees were thinned at FB. The final number of fruit at harvest was less than the amount established at FB, or at the 20-mm fruitlet stage. There were significant differences between treatments in final fruit numbers per TCSA, which reflected the different crop loads. Fruit weights and SSC values were highest with the lowest crop load, and decreased with increasing crop loads.There was also a strong crop-load effect on the extent of return bloom per tree in the subsequent year. Trees thinned at FB had significantly more flower clusters than those thinned at the 20-mm fruitlet stage of. Untreated control trees had the lowest number of flower clusters. The amount of return bloom declined with increasing crop load. Second year crop loads and fruit weights were highest when trees were thinned at FB to two or four apples cm-2 TCSA in the previous year. Trees with the highest crop load had the lowest crop load in the following year. Fruit quality was generally high for all treatments.
Abstract
Forsøk har synt at det mest vanlege dekkesystemet over søtkirsebær i Noreg kan nyttast både som eit alternativ og eit supplement til sprøytingar med kjemiske middel mot rotesoppar som angrip søtkirsebærfrukter.
Abstract
Due to a late harvesting season compared to that found in other European countries, the sweet cherry industry in Norway is now expanding, aiming for export markets. Cultivars producing high quality fruit that ripen late (late July and throughout August) and that are suitable to grow in high density production systems are sought. In addition, early ripening cultivars are sought for local marketing in early and middle July. Testing cultivars and advanced selections has been carried out at Ullensvang Research Centre since 1959. During the last decade, 130 cultivars and advanced selections have been included in the testing program. Important parameters like fruit size, fruit firmness, low fruit cracking, high and precocious yield, fresh appearance and good flavour have been evaluated. Based on the results from this testing program, the following cultivars are currently recommended: a) for early season: `Burlat", `Moreau" and `Merchant", b) for mid-season: `Giorgia", `Chelan", `Samba", `Techlovan" and `Van", c) for late season: `Lapins", `Kordia", `Regina" and `Sweetheart".
Abstract
Some high density sweet cherry orchards in Norway suffer from decay of trees resulting in death or reduced vigour of trees. A survey monitoring healthy and infected trees from several orchards found differences between cultivars and rootstocks in sensitivity of tree decay. In order to investigate this cherry tree decay further, new field trials were established in 2002 with trees of the cultivar Van grafted on the two rootstocks Prunus avium seedling and Colt and trained as central leader trees. Two parallel trials were planted; one in the soil of an old cherry orchard and the other in the soil from agricultural land where no fruit production had been conducted in advance. During the first years significant larger annual vegetative growth measured as trunk girth, annual shoot growth and leaf areas were registered from the trees growing in the virgin soil. In the replanted cherry soil, trees grafted on the rootstock Colt grew more vigorously than the seedling rootstock based on leaf areas and shoot growth measurements. The rootstock Colt may be the answer for avoiding cherry replant diseases.
Abstract
No abstract has been registered
Abstract
Histological properties of the graft union between a rootstock and scion may provide a mechanistic explanation why dwarfing rootstocks are able to reduce the growth of the tree. In order to investigate the relationship between growth and the amount of functional xylem tissue of potted sweet cherry trees, an experiment was conducted during 2002-2003. One year old field budded and bench grafted (from greenhouse) sweet cherry trees of the cultivars Van, Ulster and Lapins in all combinations of the three rootstocks Prunus avium seedling, Colt and Gisela 5 were grown in pots for two growing seasons. After shoot extension had terminated when trees were in full leaf the second year, the total growth of the different parts of the trees and the functional area using safranin staining were measured. The total mass production (tree dry weight, the length of two year old wood and number of leaves) was significantly larger in the budded trees. Similarly the trunk cross sectional area was significantly larger 10 cm above and in the middle of the graft union, but not 10 cm below it. The Colt trees were the most vigorous followed by the seedling and Gisela 5. Minor differences between the different cultivars were registered. Xylem staining with aqueous safranin combined with quantitative image analysis showed that the rootstock stem had a higher proportion of stained tissue than the scion stem. Sections taken in the middle of the graft tissue and 10 cm above showed that the proportion of stained tissue declined proportionally with the distance from the roots. The total area of stained stem xylem was larger for the two vigorous rootstocks compared to Gisela 5. Small differences were observed between cultivars and propagation methods.
Abstract
The performance of the plum rootstocks Marianna, Pixy and Wangenheim using St. Julien A as a standard to the cultivars `Avalon", `Edda", `Excalibur", `Jubileum", `Reeves" and `Victoria" was assessed in a field trial in western Norway at 60" North. Trees were planted in spring 1999, the plant material was one-year-old whips, spaced 2.0 x 4.5 m and formed with a central leader as free spindles. Soil management was grass in the alleyways and herbicide strips 1-m wide along the tree rows. Tree vigour, yield, fruit size and yield efficentcy were evaluated for the six subsequent years. Tree size was significantly affected by the rootstocks after six years growth. Wangenheim produced the smallest and St. Julien A and Pixy the largest trees as measured by trunk cross-sectional area in average for the different cultivars. St. Julien A and Pixy were the most productive rootstocks for the cultivars. However, Pixy produced significant larger yields per tree to the cultivar `Reeves" than St. Julien A. Trees on Pixy were the most yield efficient for all cultivars with the exception of `Victoria". The fruit sizes were in general large for all cultivars and became little affected by the different rootstocks. Fruit quality characterized by the content of soluble solids was in general high and did not differ between trees on the various rootstocks. The cultivar `Avalon" had the highest contents of soluble solids.
Authors
Mekjell MelandAbstract
During the period 1998-2000, thinning trials were conducted using bloom thinners on mature European plum trees at Ullensvang and at fruit growers sites in western Norway. In 1998, unsprayed control and handthinned `Victoria" trees were compared with trees treated at full bloom with a single application of 1% Armothin® or 1.5% ammoniumthiosulphate (ATS). The same program was conducted in the following two years with the addition of a single full bloom treatment with 250 ppm ethephon and a post-bloom application one month after full bloom with the mixture 10 ppm 1-napththaleneacetic acid (NAA) and 75 ppm ethephon. High volume sprays were conducted the first two years and low volume the last year. Thinning trials testing 1-1.5 % ATS and 5-7 % lime sulphur in comparison with unthinned and handthinned trees to the cultivars `Opal" and `Victoria" were conducted in 2000, at growers sites. Generally, thinning treatments reduced crop load and enhanced fruit quality (fruit size, soluble solid content, fruit firmness and ground and surface colour), but the results varied from year to year. Fruit set was reduced to about half of control values and the percentage of class 1 fruits was doubled compared to the control trees. High volume sprays to running off was more effective than low volume. The cultivar `Opal" was more sensitive to ATS than `Victoria" and a low dosage recommended. All thinning compounds caused some minor leaf injury but no fruit damage. The flower thinners were efficient at rather low temperture. No differences in the amount of gummosis (internal disorder of the fruits) were observed due to treatments on the `Victoria" plums. Return bloom was improved by thinning. In conclusion, a single dilute application at full bloom of 1% Armothin®, 1.5% ATS or 250 ppm ethephon or one application of the mixture 10 ppm NAA-75 ppm ethephon four weeks after bloom reduced fruit set and crop load and increased the fruit quality and return bloom to the cultivar `Victoria". Similar results gave one dilute spray with 1 % ATS or 5 % lime sulphur at full bloom to the cultivar `Opal".
Abstract
Betre lystilhøve i frukttrea aukar veksten hjå tre og frukter, og fruktkvalitetsfaktorar som farge og oppløyst turrstoff vert betre. Sjølv om daglengda under norske veksttilhøve er lang, er den samla lystilgangen mindre enn på sørlegare breiddegrader pga den korte vekstsesongen. Metodar som aukar ljostilgangen, t.d. lysreflekterande duk under trea, vil vera gunstig for norsk fruktdyrking. Ein har prøvd ein voven plast duk (Extenday (R)) i frukthagar på Vestlandet. Der radavstanden var 4 m, har ein strekt ut 3m brei duk på bakken langs køyregangane og festa med gummiband til trea på kvar side. Der radavstanden var 5 m, nytta ein 4m brei duk. Duken låg ute frå midten av juni til etter hausting. Det var ingen temepratureffekt av duken. Men det var 5 gonger så mykje lys i trekruna hjå tre som sto i felt med reflekterande duk i høve til kontroll tre. I køyregangen var det 3 gonger så mykje lys over duk som i køyregangar med gras. I Aroma var eple frå tre frå felt med duk større, søtare og med meir raud dekkfarge enn frå kontroll trea. Det var særleg stor skilnad frå eple på dei nedte greinene. Med omsyn til fastleik og syreinnhald var det ikkje sikre skilnader. Men Streif-indeks viste at refleksduken framskunda mogninga.
Abstract
I eit felt med "Excalibur" og "Prinlew" plommer vart køyregangen dekka med kvit reflekterande duk for å betra ljostilhøva i trekruna. Duken låg i hagen frå 2 veker etter bløming til etter at plommene var hausta i midten av september. Der det ikkje var nytta reflekterande duk var fruktene nede på treet grønare, hadde mindre dekkfarge og lågare innhald av oppløyst turrstoff enn fruktene oppe i trekrunene. Fruktene frå tre som hadde stått over reflekterande duk var like godt farga og hadde same syrinnhald og fastleik om dei var hausta oppe eller nede på trea. Men det var også for desse trea høgare innhald av oppløyst turrstoff i fruktene oppe i trea i høve til dei som hadde vakse nedst i trea. Reflekterande duk gav jamnare mogning hjå plommene oppe og nede i trea. Dermed kan ein klara seg med færre haustingar. Temperaturen var ikkje heva der ein nytta duk, og duken svekka grasveksten i køyregangane.
Abstract
Combinations of covering and fungicide applications were tested on two sweet cherry cultivars; Van during two years (2001 and 2002) and Lapins three years (2001"2003). The following treatments were tested in 2001 and 2002: (i) covering during flowering and from 5 to 6 weeks prior to harvest and throughout harvest, no fungicides applied, (ii) as (i) but fungicides were applied once or twice between the two covering periods, (iii) covered 5 to 6 weeks prior to harvest and throughout harvest, fungicides applied two or three times prior to covering, and (iv) uncovered throughout the season, fungicides applied two or three times in the period from flowering towards harvest. In 2003, the trees were covered only from 5 to 6 weeks prior to harvest and throughout harvest. Both treatments that year received fungicide applications during flowering, but one of the treatments was left unsprayed during the green fruit period prior to covering. Every combination of covering and fungicide applications reduced total fruit decay at harvest significantly compared to a full fungicide programme and no covering. In three of four trials when the trees were covered during flowering and prior to harvest, and fungicide applications were omitted in the green fruit phase between the covering periods, no significant increase in fruit rot occurred compared to treatments where fungicides were applied. However, in one trial there was a significant increase in fruit rot by leaving out one fungicide spray during that intermittent period. Furthermore, if fungicides were only applied during flowering and not on green fruit before covering in 2003, a significant increase in fruit rot occurred. Thus, leaving out fungicide applications during that supposedly less susceptible green fruit period, increased the risk of acquiring fruit rot. Applying fungicides during the green fruit stage significantly reduced the amount of brown rot in four of five trials and anthracnose in one of five trials. No negative effect on fruit quality was found from the extended covering periods. It can be concluded that covering effectively replaced fungicide applications during flowering and prior to harvest.
Abstract
The performances of the plum rootstocks Plumina® Ferlenain, Ishtara® Ferciana, Jaspi® Fereley and the pentaploid open pollinated seedling of Mariana P 8-13 compared with St. Julien A as a standard, for the cultivars "Opal" and "Reine Claude GF 1119" were assessed in a field trial in western Norway at 60" North. This trial was one part of an international plum rootstock trial located in seven European countries and organized from INRA Bordeaux. Trees were planted in spring 1994; spaced 2.0 x 4.0 m and formed with a central leader as free spindles. Soil management was grass in the alleyways and herbicide strips 1-m wide along the tree rows. Tree vigour, yield, fruit size and yield efficiency were evaluated for the seven subsequent years. Tree size was significantly affected by the rootstocks. P 8-13 produced the largest trees for both cultivars as measured by trunk cross-sectional area. The smallest trees were produced on Plumina® Ferlenain for the cultivar `Opal" and on Jaspi® Fereley for `Reine Claude". The cultivar `Opal" was the most productive and gave three times larger crop than "Reine Claude" on average for the six cropping years. The "Reine Claude" trees came two years later into production than "Opal". There were small differences between the different rootstocks in productivity: However, the rootstock Plumina® Ferlenain produced significant lower crop than the other rootstock for `Opal". Trees on Jaspi® Fereley were the most yield efficient for `Opal" and Plumina® Ferlenain for `Reine Claude". The fruit sizes were in general medium to small for both cultivars and became little affected by the different rootstocks. The average fruit size was about 29 g for `Opal" and 22 g for `Reine Claude". Fruit quality characterized by the content of soluble solids was high for `Reine Claude" with average 20 % and 15 % for `Opal" and did not differ much between trees on the various rootstocks.
Authors
Mekjell MelandAbstract
No abstract has been registered
Authors
Mekjell MelandAbstract
No abstract has been registered
Abstract
No abstract has been registered
Abstract
No abstract has been registered
Abstract
No abstract has been registered
Authors
Mekjell MelandAbstract
No abstract has been registered
Abstract
Resultat frå forsøk med ulike dekkesystem for søtkirsebær sin effekt på mikroklima og fruktkvalitet er skildra i ein vitskapleg artikkel på engelsk. Resultata er delvis publisert på norsk i følgjande artikkel: Børve, J., A. Stensvand & M. Meland, 1997. Verknad av plastdekking på rotning hjå søtkirsebær. Informasjonsmøte i plantevern 1997 Grønn forskning 2/97. 252-255.
Abstract
Årleg turrstoffproduksjon vart estimert frå åtte år gamle epletre med sortane "Fuji", "Royal Gala" og "Braeburn" poda på grunnstamma M9 og forma som slank spindel. Både frisk- og turrstoffproduksjon auka liniært med mengda av ljos som vart oppfanga i trea. Denne samanhengen tilsvarar ei avling på 16.9 tonn pr. daa med ei ljosoppfanging på 90 %. Energien som vart omdanna frå ljos i vekstsesongen til turrstoff i New Zealand var tilsvarande som i England. Skilnaden mellom desse to landa er at New Zealand har ein lengre vekstsesong og høgare innstråling. Turrstoffproduksjonen var fordelt til frukt, treaktig vev og blad med ei fordeling til frukt på 74, 72 og 63% for dei tre sortane "Braeburn", "Fuji" og "Royal Gala".
Authors
Mekjell MelandAbstract
An intensive field planting of `Edda", "Opal" and "Mallard" plum trees (Prunus domestica L.) all grafted on the semidwarf rootstock St. Julien A was established in 1993 at Ullensvang Research Centre, western Norway at 60 ° North. The objectives were to evaluate four different single row planting systems (vertical axis, free spindle, hedgerow and Y-trellis) and three planting densities ( 0.5, 1.0, 1.5 x 4 m for the Y-trellis and hedge trees and 2.0 x 4 m for the central leader trees) in a northern climate. These planting distances give a range of tree density of 1250 - 5000 trees per ha. The experiment gave a small yield in the third leaf on all canopy systems. During the first four cropping years, the yields/ha were positively correlated with tree density. Cumulative yield per hectare was highest on the Y-trellis and hedge trees with the highest density (5000 trees per ha). In the fourth leaf, the Y-trellis trees gave 15 tons per hectare. No differences in fruit size or the soluble solids content among canopies or densities were found.
Abstract
The cherry cultivars "Van", "Ulster" and "Burlat" grafted on the rootstocks seedling, `Colt" and `Gisela 5" were evaluated for important fruit quality parameters at Ullensvang Research Centre during the 1998 season. The largest fruit size was found on the cultivar/rootstock combinations `Van"/seedling, `Ulster/Colt" and `Burlat/Gisela 5". Other parameters like fruit firmness, stone weight, soluble solids, titratable acids and pH of the fruit juice were registered as well.
Abstract
No abstract has been registered
Abstract
No abstract has been registered
Abstract
No abstract has been registered
Abstract
No abstract has been registered
Academic – Rain covers against cracking for sweet cherry orchards
Mekjell Meland, Kjersti Skjervheim
Abstract
No abstract has been registered
Authors
Mekjell MelandAbstract
No abstract has been registered
Abstract
No abstract has been registered
Abstract
No abstract has been registered
Authors
Mekjell MelandAbstract
No abstract has been registered
Authors
Mekjell MelandAbstract
No abstract has been registered
Abstract
No abstract has been registered
Abstract
No abstract has been registered
Abstract
No abstract has been registered
Abstract
No abstract has been registered
Authors
Mekjell MelandAbstract
No abstract has been registered
Abstract
No abstract has been registered
Abstract
No abstract has been registered
Authors
Mekjell MelandAbstract
No abstract has been registered
Abstract
No abstract has been registered
