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Neufahrn bei Freising, Germany

Meiners J.,Leibniz University of Hanover | Debener T.,Leibniz University of Hanover | Schweizer G.,Institute for Crop Science and Plant Breeding | Winkelmann T.,Leibniz University of Hanover
Scientia Horticulturae | Year: 2011

Helleborus is a genus of herbaceous perennials belonging to the family Ranunculaceae. Within this genus six sections with a total of 22 species are found. The largest section Helleborastrum contains 16 species for which genetic relationships are still unclear. This study represents the first genetic analysis in the genus Helleborus, including the two newly described species H. liguricus and H. abruzzicus based on multilocus amplified fragment length polymorphism (AFLP) markers with a genome-wide distribution in combination with nuclear DNA content data. Chromosome analyses of roots tips revealed a number of 2. n= 32 for the selected species, which was congruent with previous observations. The nuclear DNA content of Helleborus was estimated by flow cytometry applying propidium iodide staining and varied between 18 and 33. pg/2C, depending on the species. For AFLP analyses, 19 out of the 22 Helleborus species were studied using 10 AFLP primer combinations, resulting in a total of 1109 polymorphic bands among all species including the outgroup. The genetic distances between species varied between 0.034 and 0.330. Based on genetic distances a phenogram using the Neighbor-joining cluster method with bootstrap analysis was calculated. The results support the previously suggested division of the genus into six sections and thereby approve AFLP data to be applicable for phenetic analyses. Moreover, this genetic information is significant for the development of future Helleborus breeding strategies. © 2010 Elsevier B.V. Source

Hsam S.L.K.,TU Munich | Mohler V.,Institute for Crop Science and Plant Breeding | Zeller F.J.,TU Munich
Journal of Applied Genetics | Year: 2014

The genetics of resistance to powdery mildew caused by Blumeria graminis f. sp. avenae of four cultivated oats was studied using monosomic analysis. Cultivar 'Bruno' carries a gene (Pm6) that shows a recessive mode of inheritance and is located on chromosome 10D. Cultivar 'Jumbo' possesses a dominant resistance gene (Pm1) on chromosome 1C. In cultivar 'Rollo', in addition to the gene Pm3 on chromosome 17A, a second dominant resistance gene (Pm8) was identified and assigned to chromosome 4C. In breeding line APR 122, resistance was conditioned by a dominant resistance gene (Pm7) that was allocated to chromosome 13A. Genetic maps established for resistance genes Pm1, Pm6 and Pm7 employing amplified fragment length polymorphism (AFLP) markers indicated that these genes are independent of each other, supporting the results from monosomic analysis. © 2014 Institute of Plant Genetics, Polish Academy of Sciences, Poznan. Source

Kammhuber K.,Institute for Crop Science and Plant Breeding
BrewingScience | Year: 2012

Hop has three groups of variety-specific ingredients. These are the bitter substances, the essential oils and also some low molecular weight polyphenols like the flavonoids. In this work the focus was mainly on the composition of the quercetin- and kaempferol-glycosides, because these compounds are suitable to differentiate varieties. Initial work focused on the development of convenient methods for sample preparation and HPLC-analysis. Then nearly the whole available world hop collection (121 different varieties from 17 countries) was analysed. The data were evaluated by a principal component analysis to make differences and similarities visible. Some varieties are clearly distinguished from their polyphenol composition, while others, especially the old land races, were barely distinguishable from each other. Source

Wenzel A.,TU Munich | Frank T.,TU Munich | Reichenberger G.,Institute for Crop Science and Plant Breeding | Herz M.,Institute for Crop Science and Plant Breeding | Engel K.-H.,TU Munich
Metabolomics | Year: 2015

The aim of the study was to investigate the impact of drought stress on the metabolite profiles of barley (Hordeum vulgare L.) grain against the background of natural variability depending on growing location and season. Six barley genotypes were field-grown (i) under normal weather conditions at two different sites and (ii) under induced drought conditions, using a Rain-Out-Shelter. Both trials were performed in three consecutive seasons (2010–2012). Samples were subjected to a gas chromatography-mass spectrometry metabolite profiling procedure, based on the extraction and fractionation of a broad spectrum of low molecular weight metabolites ranging from lipophilic (e.g. triglyceride-derived fatty acids, free fatty acids, fatty alcohols, sterols) to hydrophilic (e.g. sugars, sugar alcohols, acids, amino acids and amines) compounds. The comparative assessment of the profiling data by means of multivariate analyses revealed that differences in lipophilic metabolites were mainly due to seasonal impact. In contrast water deficit was strongly reflected in quantitative changes of polar metabolites, irrespective of natural variability. The impact factor growing location was differently pronounced depending on the growing season. Univariate statistical analysis revealed 17 metabolites, including the monosaccharides fructose and glucose, the trisaccharide raffinose, several organic acids and the biogenic amine γ-aminobutyric acid to be significantly (p-value < 0.01) influenced by drought stress conditions. © 2014, Springer Science+Business Media New York. Source

Gschwendtner S.,TU Munich | Reichmann M.,Institute for Crop Science and Plant Breeding | Muller M.,Institute for Crop Science and Plant Breeding | Radl V.,TU Munich | And 2 more authors.
Plant and Soil | Year: 2010

In this study, the potential effects of a genetically modified (GM) amylopectin-accumulating potato line (Solanum tuberosum L.) on plant beneficial bacteria and fungi as well as on phytopathogens in the rhizosphere were investigated in a greenhouse experiment and a field trial. For comparison, the non-transgenic parental cultivar of the GM line and a second non-transgenic cultivar were included in the study. Rhizospheres were sampled during young leaf development (EC30) and at florescence (EC60). The microbial community composition was analysed by real-time PCR to quantify the abundances of Pseudomonas spp., Clavibacter michiganensis, Trichoderma spp. and Phytophthora infestans. Additionally, total bacterial and fungal abundances were measured. None of the examined gene abundance patterns were affected by the genetic modification when wild type and GM line were compared. However, significant differences were observed between the two natural potato cultivars, especially during the early leaf development of the plants. Furthermore, gene abundance patterns were also influenced by the plant developmental stage. Interestingly, the impact of the cultivar and the plant vegetation stage on the microbial community structure was more pronounced in field than in greenhouse. Overall, field-grown plants showed a higher abundance of microorganisms in the rhizosphere than plants grown under greenhouse conditions. © 2010 Springer Science+Business Media B.V. Source

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