Oddmund Frøynes
Rådgiver
(+47) 959 06 027
oddmund.froynes@nibio.no
Sted
Ullensvang
Besøksadresse
Ullensvangvegen 1005, 5781 Lofthus
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Forfattere
Fuad Gasi Naris Pojskić Belma Kalamujić Stroil Oddmund Frøynes Milica Fotirić Akšić Mekjell MelandSammendrag
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.
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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.
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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.
Forfattere
Mekjell Meland Milica Fotiric Aksic Oddmund Frøynes Almira Konjic Lejla Lasic Naris Pojskic Fuad GasiSammendrag
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.
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Hjartenøtt er ein ny art for kommersiell produksjon i Norge. Endå om det sporadisk er planta nokre valnøtt-tre gjennom tidene, finst det lite og ikkje systematisert kunnskap om dyrking, sortar og produktkvalitet under norske forhold. Erfaringar frå Danmark og Sør-Sverige er det næraste me kjem tilhøve som liknar dei beste dyrkingsområda i Norge. Denne dyrkingsrettleiinga omtalar vekst og utviklinga av hjartenøtt-treet, oppal av trea, gjødsling, stell og drift, hausting, plantevern og omtale av sortar.
Forfattere
Mekjell Meland Milica Fotiric Aksic Radosav Cerovic Oddmund Frøynes Clive Kaiser Frank MaasSammendrag
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.
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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.
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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.
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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.
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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.
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Nibio Ullensvang har i perioden 2008-2017 gjennomført rettleiingsprøving av samla 20 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 Rubinstep, Your Choice og Aroma ‘Fagravoll’ vert tilrådde til kommersiell fruktdyrking. Sorten Blyberg er tilrådd for småhagebruket medan sortane Lotos og Wellant bør prøvast vidare. På grunn av svak fruktkvalitet og sein modning er fylgjande sortar og utval ikkje tilrådde for dyrking under norske tilhøve: L II 3/05-09, Sonja, L II 1/08-09, NA 42-51, MA982 06059, Ritt Bjerregaard, Dalili Ambassy, Initial, Gala Must, Topas, Greenstar og Kanzi.
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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.
Forfattere
Mekjell Meland Oddmund Frøynes Milica Fotiric Akšic Naris Pojskic Belma Kalamujic Stroil Lejla Lasic Fuad GasiSammendrag
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.
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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.
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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.
Forfattere
Fuad Gasi Oddmund Frøynes Belma Kalamujic Stroil Lejla Lasic Naris Pojskic Milica Fotiric Aksic Mekjell MelandSammendrag
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.
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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.
Populærvitenskapelig – Eplesorten ‘Asfari’ - eit eple utan dekkfarge
Oddmund Frøynes, Mekjell Meland
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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.
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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.
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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.
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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".
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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.
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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.
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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.
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The performances of the plum rootstocks Ferlenain, Ishtara, Jaspi and 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 Ferlenain for the cultivar `Opal" and on Jaspi 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 Ferlenain produced significant lower crop than the other rootstock for `Opal". Trees on Jaspi were the most yield efficient for `Opal" and 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 30 g for `Opal" and 25 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.
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Observasjonar om blomstringstid, blomstermengd og fruktsetting vart innsamla frå sortsprøvefelta i søtkirsebær ved Bioforsk Ullensvang forskingssenter i perioden 1993 – 2005. Sortane var poda på grunnstammene Colt, Prunus avium L. frøstamme og Gisela 5. Det var tydelege skilnader i blomstringstid og - mengd mellom dei ulike sortane, mellom tre på ulike grunnstammer og åra. Blomstringstida har starta tidlegare i dei siste åra. Dei mest avlingssikre sort/grunnstamme-kombinasjonane har både høg blomstermengd og fruktsettingsgrad. Ei oppdatert liste over kva sterilitetsgruppe sortane høyrer heime i er presentert.
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I den seine norske plommesesongen saknar ein gode kvalitetssortar. Mildare vêr i siste halvdel av september og fyrst i oktober i seinare år, gjer at sortar som modnar sist i september er meir aktuelle og dyrka enn før. Den kanadiske plommesorten Valor har vorte dyrka i grannelanda våre i dei siste åra og er kjenneteikna med tidleg og stor avling og med mørkeblå, store frukter av høg kvalitet. Innleiande prøvedyrking av denne plommesorten ved Bioforsk Ullensvang stadfester desse eigenskapane.
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Denne artikkelen gjer greie for dyrkingsverdi og kvalitetseigenskapar hjå 19 søtkirsebærsortar som modnar i første halvdel av sesongen.
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Dyrkingseigenskapar av 21 søtkirsebærsortar vart vurderte ved Bioforsk Ullensvang: Fylgjande søtkirsebærsortar har gode eigenskapar: Chelan, Giorgia, Samba, Techlovan og Van med modning i siste veka i juli og Lapins, Kordia, Regina og Sweetheart sist i sesongen. I tillegg er Stardust aktuell sort med ljos raud dekkfarge.
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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 6 years, approximately 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 are 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".
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Some high density sweet cherry orchards in Norway suffer from decay of trees resulting in death or reduced vigour of trees. A survey has been conducted monitoring healthy and infected trees from several orchards. The nutritional statuses of the soil and in the trees were in general in accordance with general accommodation. Different species of root nematodes were identified with levels above the damage of thresholds. Neither insects, diseases, bacterials nor virus were registered as the main reason for this dieback. However, differences between cultivars and rootstocks sensitivity were observed. In order to investigate this cherry tree decay further, new field trials were established in 2001 with trees of the cultivars Van and Kristin grafted on the two rootstocks Prunus avium seedling and Colt and trained as a central leader trees. Two parallel trials were planted; one in the soil of on old cherry orchard and the other in the soil from agricultural land where no fruit production has been conducted in advance. During the first years significant larger annual vegetative growth measured as trunk cross sectional area and annual shoot growth were registered from the trees growing in the agricultural 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 first significant crop is expected in 2005.
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Sweet cherry trees sometimes suffer from dieback symptoms under Scandinavian growing conditions. Some combinations of cultivars and rootstocks are more susceptible to this than others. The graft union between a rootstock and a scion is a junction between two different tissues. Differences in tissue development in the union may provide a mechanistic explanation of inhibiting transport of water and nutritional substances and likely inhibit growth of the scion. 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 green house) 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 quantification of functional area using safranin staining were conducted. The total mass production (tree dry weight, the length of two year old wood and number of leaves) was significant larger in the budded trees. Similarly the trunk cross sectional area was significant larger 10 cm above and in the middle of the graft union, but not 10 cm below. The Colt trees were the most vigorous followed by the seedling and Gisela 5. Small 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 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.
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Trees of `Discovery" apples growing on dwarf and semi-dwarf rootstocks were assessed in field trials at two sites (western and eastern Norway) at 60° North. The rootstocks included two selections of M.9 (EMLA, RN.29), two from the Polish (P) series (P.59, P.60), three from the Geneva (G) series (G.30, G.78730-026, G.202) and M.26. Trees were planted in the spring 1997 as two years old feather trees, spaced 1.5 x 4 m, trained as slender spindles and evaluated for five subsequent years. Soil management were grass in the alleyways and herbicide strips 1-m wide along the tree rows. Tree size was significantly affected by the rootstocks after five years growth. P.59, G.78730-026 and M.9 RN.29 produced the smallest and G.30 and G.202 the largest trees as measured by trunk cross-sectional area. P.59 and G.30 had the greatest yields per tree, followed by G.202, P.60 and M.9 EMLA. Trees on P.59 were the most yield efficient followed by the two M.9 clones. The fruit density measured as number of fruits per trunk-cross-sectional area showed similar results. The different rootstocks affected little the fruit weights. Fruit quality characterized by the content of soluble solids was in general high and did not differ between trees on the various rootstocks.
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Pollineringstilhøve hjå viktige plommesortar, både nye og eldre, er presenterte. Avalon og Reeves har dårleg pollen, medan Excalibur og Jubileum har godt pollen. For å sikra god pollinering i Reeves er tilrådd å ha to pollensortar i plantinga - Althanns og Opal eller Victoria.
Forfattere
Oddmund FrøynesSammendrag
Sortstilfanget til nasjonal prøving av søtkirsebærsortar i Noreg er god. Sidan 1959 har det vore drive sortsprøving i søtkirsebær ved Ullensvang forskingssenter, Lofthus. Prøvinga har resultert i lansering av ei rad sortar. Forrige sortslisterevisjon vart gjort i 1998. Viktige sortseigenskapar i utprøvinga av søtkirsebærsortar er: fruktfastleik , årviss og høg avling, fruktstorleik, smak, motstand mot rotesoppar, sprekkemotstand og sjølvfertilitet. Berre mørkfarga sortar står på lista. Sortimentet tek sikte på å dekka den norske frisk-konsummarknaden frå 2.veka i juli til ca. 20. august og eksportmarknaden frå ca. 25. juli og ut sesongen. Fylgjande sortar er aktuelle for dyrking i Noreg (sette opp i modningsrekkefylgje): "Moreau", "Burlat", "Merchant", "Vista", "Giorgia", "Chelan"â, "Samba"â, "Techlovan"â, "Ulster", "Van", "Kristin", "Stella", "Sylvia", "Lapins" og "Regina".
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Vi prøver i denne artikkelen å gje eit oppdatert oversyn over det vi veit om pollinering i aktuelle eplesortar. Vi drøftar kva omsyn som må takast ved val av pollensort, og har sett opp ein tabell der ein kan gå inn og finne aktuelle kombinasjonar av hovudsort og pollensort. Målgruppe for artikkelen er dyrkarar og rettleiarar.
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Eit dyrkingsproblem er at søtkirsebær-trea utan synlege sjukdomsteikn brått kan stagnera i vekst og døy endå om feltet har fått optimalt stell. For tida er det ingen konkrete rådgjerder for dyrkarane bortsett frå å planta nye tre i staden for dei som gjekk ut. Med finansiering frå Statens Landbruksbank har Planteforsk Ullensvang i samarbeid med Planteforsk Plantevernet gjennomført det eitt-årige prosjektet "Kartlegging av årsaker til tredaude i søtkirsebær" i 1999. Kartleggingsarbeidet var delt i to: 1.Kartlegging av 5 bruk som har problem med tredaude blant medlemene til Hardanger Frukt og Bær med utttak og analyse av nematode-, sopp-, virus- og jord- og bladprøvar saman med feltinspeksjonar. 2. Spørjeundersøking til søtkirsebærdyrkarar ved 5 fruktlager i Ullensvang om tilhøve som kan tenkjast å påverka tredaude i søtkirsebær . Grupper av rotnematodar som gjer skade på frukttrea var registrert i alle hagane og kan såleis vera medverkande til symptoma. Det var også mogeleg å relatera høge populajonar av rotsårnematodar til dårleg tilvekst og høge spiralnematodetal til tidlegare observasjonar av tredaude. Det vart ikkje påvist at ulike insekt, soppar, bakteriar eller virus var primærårsak til denne tredauden. Spørjeundersøkinga viste at mange søtkirsebærdyrkarar meinte det var skilnad mellom kor utsette ulike sortar og grunnstammer var for tredauding i frukthagane. Gjenplanting på same arealet kort tid etter at det var rydda steinfruktplanting fremja tredauding. Lauvtrebarkbillen var årsak til tredaude, men då er diagnosen oftast enkel å stilla.
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Eit dyrkingsproblem er at søtkirsebær-trea utan synlege sjukdomsteikn brått kan stagnera i vekst og døy endå om feltet har fått optimalt stell. For tida er det ingen konkrete rådgjerder for dyrkarane bortsett frå å planta nye tre i staden for dei som gjekk ut. Med finansiering frå Statens Landbruksbank har Planteforsk Ullensvang i samarbeid med Planteforsk Plantevernet gjennomført det eitt-årige prosjektet "Kartlegging av årsaker til tredaude i søtkirsebær" i 1999. Dette var eit oppdrag for Hardanger Frukt og Bær. Kartleggingsarbeidet var delt i to: 1. Kartlegging av 5 bruk som har problem med tredaude blant medlemene til Hardanger Frukt og Bær med utttak og analyse av nematode-, sopp-, virus- og jord- og bladprøvar saman med feltinspeksjonar. 2. Spørjeundersøking til søtkirsebærdyrkarar ved 5 fruktlager i Ullensvang om tilhøve som kan tenkjast å påverka tredaude i søtkirsebær . I desse fem søtkirsebærhagane, var næringstilstanden av makronæringsemne i jorda høg og delvis over det optimale. Ubalanse mellom næringsemna kan vera med og svekka trehelsa til trea. Grupper av rotnematodar som gjer skade på frukttrea var registrert i alle hagane og kan såleis vera medverkande til symptoma. Det var også mogeleg å relatera høge populajonar av rotsårnematodar til dårleg tilvekst og høge spiralnematodetal til tidlegare observasjonar av tredaude. Det vart ikkje påvist at ulike insekt, soppar, bakteriar eller virus var primærårsak til denne tredauden. Grundigare undersøkingar og då særleg av nematodar i jorda bør utførast vidare for å påvisa årsaker til denne tredauden i søtkirsebær og finna mogelege rådgjerder for å bekjempa dei ulike potensielle skadegjerarane. Spørjeundersøkinga viste at mange søtkirsebærdyrkarar meinte det var skilnad mellom kor utsette ulike sortar og grunnstammer var for tredauding i frukthagane. Gjenplanting på same arealet kort tid etter at det var rydda steinfruktplanting fremja tredauding. Lauvtrebarkbillen var årsak til tredaude, men då er diagnosen oftast enkel å stilla. Kulturmåten som gjødslings- og vatningspraksis verkar mindre inn, men vass-sig på trerøtene var negativt.
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