Publications
NIBIOs employees contribute to several hundred scientific articles and research reports every year. You can browse or search in our collection which contains references and links to these publications as well as other research and dissemination activities. The collection is continously updated with new and historical material.
2010
Abstract
No abstract has been registered
Authors
J Santala O Samuilova Asko Hannukkala S Latvala H Kortemaa U Beuch A Kvarnheden Per Persson K Topp Kari Ørstad Carl Jonas Jorge Spetz S. L. Nielsen HG Kirk M Budziszewska P Wieczorek A Obrepalska-Steplowska H Pospieszny A Kryszczuk J Sztangret-Wisniewska Z Yin M Chrzanowska E Zimnoch-Guzowska E Jackeviciene L Taluntyte N Pupola J Mihailova I Lielmane L Jarvekulg K Kotkas E Rogozina A Sozonov I Tikhonovich P Horn I Broer S Kuusiene J Staniulis JG Uth G Adam JPT ValkonenAbstract
No abstract has been registered
Authors
Gudbrand Lien Subal C. Kumbhakar J. Brian HardakerAbstract
No abstract has been registered
Authors
Frank MillerAbstract
No abstract has been registered
Abstract
In this study we investigated the interaction between temperature and genotype on fruit development and levels of total phenols and anthocyanins in cloudberry. The experiment was done in a phytotron using one female (‘Fjellgull") and one hermaphroditic (‘Nyby") cultivar. Plants were grown at 9, 12, 15 and 18°C in 24-h photoperiod. The female cultivars were pollinated with pollen from a male (‘Apollen") clone and from the hermaphrodite clone. Parthenocarpic fruit development was induced by gibberellic acid (GA3). Ripe berries were frozen individually at -80°C and stored until analyses. There was a linear, double logarithmic relationship between temperature and number of days from pollination/GA3-treatment to ripening. ‘Fjellgull" had significantly larger berries than ‘Nyby", and the largest berries were obtained at 12 and 9°C. Pollen clone did not have a significant effect on berry size. GA3 induced parthenogenesis in ‘Fjellgull" and partial parthenogenesis in ‘Nyby". In ‘Fjellgull", the parthenocarpic berries were comparable to pollinated ones at low temperatures, but at 18°C their development was restricted. The level of total anthocyanins was significantly higher in ‘Fjellgull" than in ‘Nyby", and these levels were significantly enhanced at 9 and 12°C compared to higher temperatures. Levels of total phenolic compounds were not significantly affected. In conclusion, the present results indicate that low temperature is favourable both for size and quality of cloudberries.
Authors
Jens Rohloff Per Winge Jahn Davik May Bente Brurberg Keithanne Mockaitis Vladimir Shulaev Stephen K, Randall Atle M. Bones Muath AlsheikhAbstract
In order to support functional genomics research in octoploid (Fragaria x ananassa Duch.) and diploid (F. vesca) strawberry, a customized Fragaria microarray chip was developed as a joint collaboration between Graminor Breeding Ltd. and NTNU. F. vesca cDNA sequences were provided by The Center for Genomics and Bioinformatics, Indiana University (an assembly of >3 million reads from GS-FLX Titanium - Roche/454 Life Sciences sequencing), and about 59,000 publicly available Fragaria EST sequences were uploaded from NCBI. In addition, ~190 Mb of preliminary draft genome sequences from F. vesca were provided by the Strawberry Genome Sequencing Consortium (courtesy to V. Shulaev). cDNAs used as templates for probe design were validated by BlastN against the F. vesca draft genome excluding cDNAs of microbial origin. Genes not represented in the cDNA collection were identified by screening F. vesca draft genome against protein sequences from Arabidopsis thaliana, Vitis vinifera, Ricinus communis and Populus trichocarpa. Exon sequences from genes not found in the cDNAs were included. In total, 43723 unique 60-mer probes were designed and the Agilent eARRAY tool was used to produce a 4x44k format microarray chip. Fragaria chip applicability and feasibility for transcriptional profiling was investigated using either abiotic (low temperature) or biotic (pathogenic fungi) stress treatment. Microarray data will be subsequently integrated with other omics data to address gene-regulatory networks and biological functions. Cold acclimation experiments were focused on short- and long-term effects in meristematic tissue, and revealed the up-regulation of ~100 cold-responsive genes (transcription factors, dehydrins, enzymes), and transcripts involved in starch breakdown and raffinose biosynthesis. Beside central metabolism, secondary metabolism was also strongly modulated as seen by changes in the expression of flavonoid biosynthesis-related genes. Time-course studies of transcriptional responses in F. vesca accessions showing contrasting resistance toward the pathogen Phytophthora cactorum are in progress, and will be presented in-depth.
Authors
Stein Tomter Gro Hylen Jan-Erik Ørnelund NilsenAbstract
No abstract has been registered
Authors
Igor A. Yakovlev Carl Gunnar Fossdal Øystein JohnsenAbstract
Norway spruce (Picea abies (L.) H. Karst.) displays a temperature-dependent epigenetic memory from the time of embryo development, which thereafter influences the timing of bud phenology. As a first step toward unravelling the molecular mechanism behind an epigenetic memory, transcriptional analysis was performed on seedlings from seeds of six full-sib families produced under cold (CE) and warm (WE) embryogenesis temperature regimes. We prepared two suppressive subtracted cDNA libraries, representing genes predominantly expressed after bud set induction in plants from seeds obtained after CE and WE embryogenesis. Sequencing and annotation revealed considerable differences in the transcriptome of WE and CE seedlings. We studied the expression patterns of 32 selected candidate genes using qRT-PCR. Five genes, two transposon-related genes and three with no matching sequence in databases showed differential expression in progeny from CE and WE correlated with family differences. Another step was to study microRNAs (miRNAs), which are endogenous small RNAs exerting epigenetic gene regulatory effects. We tested for their presence and differential expression. We then prepared concatemerized small RNA libraries from seedlings of two fullsib families, originated from seeds developed in a cold or a warm environment. One family showed distinct epigenetic effects whilst the other did not. Sequencing identified 24 novel and 4 conserved miRNAs. Further search and screening of the conserved miRNAs confirmed the presence of 17 additional miRNAs. Most of the miRNAs were targeted to unknown genes. The expression of seven conserved and nine novel miRNAs showed significant differences in transcript levels in the full-sib family showing distinct epigenetic difference in bud set, but not in the non-responding full-sib family. The differential expression of specific miRNAs indicates their putative participation in epigenetic regulation. Putative miRNA targets were studied. These findings may contribute to our understanding of the epigenetic mechanisms underlying adaptive changes acquired during embryogenesis in Norway spruce.
Authors
Heleen de Wit Toril Eldhuset Jan MulderAbstract
Dissolved aluminium (Al) in soils, mobilized by acid deposition, is considered a threat to forest health through hampering root growth and nutrient uptake. Since the end of the 1980s dissolved Al in forest soil water plays a key role in the assessment of critical loads of acid deposition. So far, most evidence for toxicity of dissolved Al in forest soil water is based on nutrient solution studies and pot experiments. Here, we present results from one of the few in situ ecosystem-scale forest manipulation experiments to study the effect of Al on mature forest trees. A plotwise addition of dilute AlCl3 was conducted during seven years in an even-aged spruce forest (Picea abies) in an area in Norway with low acid deposition. Soil solution concentrations of Al were increased to potentially toxic levels (up to 500 mu mol L-1) and base cation (Ca + Mg + K) to inorganic Al ratios in the soil solution in the root zone were mostly below 1 in the Al-addition treatments. In the control treatment (only water addition) Al concentrations did not exceed 15 mu mol L-1 and base cation to inorganic Al ratios were above 1. The toxic effects of Al on fine root growth and plant growth found in hydroponic studies and pot trials are not confirmed by this field manipulation. However, magnesium (Mg) contents in needles decreased significantly and persistently in plots with elevated Al concentrations, whereas the needle Ca content did not respond. The depletion of the Mg content in needles is suggested to be due to antagonistic effects of high Al concentrations at the root surface, consistent with observed reductions in Mg to Al ratio of inner bark. This study clearly supports a role for Al in critical load functions for forests as dissolved Al causes a decrease in uptake of Mg. However, other signs of reduced forest vitality were not observed. Soil base cation status may need to be included in risk evaluations of forest health under acid deposition. (C) 2010 Elsevier B.V. All rights reserved.
Abstract
We investigated concentrations of dissolved organic carbon (DOC) in throughfall and soil solutions at 5, 15 and 40-cm depth in 16 Norway spruce and two Scots pine plots throughout Norway between 1996 and 2006. Average DOC concentrations ranged from 2.3 to 23.1 mg/l and from 1.1 to 53.5 mg/l in throughfall water and soil solutions, respectively. Concentrations of DOC in throughfall and soil waters varied seasonally at most plots with peaks in the growing season. By contrast to recently reported positive long-term trends in DOC concentrations in surface waters between 1986 and 2003, soil water data from 1996 to 2006 showed largely negative trends in DOC concentrations and no significant trends in throughfall. However, regression analysis for individual sites, particularly at 5- and 15-cm soil depths, showed that DOC concentrations in soil water were significantly and negatively related to non-marine sulphate (SO4) and chloride (Cl-). The lack of a long-term increase in DOC in soil water in the period May 1996-December 2006 may be due to the relatively small changes in the deposition of SO4 and Cl- in this period.