IDENTIFIKACE ODRŮD ŘEPKY OLEJNÉ POUŽITÍM AFLP MARKERŮ

A new type of molecular marker, fluorescence-based AFLP, was evaluated for its ability to identify oilseed rape cultivars. Each of the six tested AFLP combinations detected polymorphisms, the best combination (MCAA/ E-ACT) had 26% of polymorphic peaks from a total of 90 peaks and could distinguish analysed cultivars, and 4 out of 5 DH lines. The results presented here show that florescence-based AFLP was, for the purposes of oil seed rape cultivar fingerprinting, a very suitable approach.Nový typ molekulárního markeru AFLP, založeného na fluorescenci, byl používán pro svou schopnost identifikovat odrůdy a homogenitu DH linií řepky olejné. Každá ze šesti testovaných AFLP kombinací detekovala polymorfismy, nejlepší kombinace (M-CAA/E-ACT) měla 26% polymorfních píků z celkového počtu 90 a bylo možné rozlišit analyzované odrůdy a 4 z 5 DH linií. Genetická podobnost byla vypočítána použitím klastrové analýzy (metody UPGMA). Ukázalo se, že genetická podobnost mezi DH liniemi je nízká, i když tyto linie byly získány mikrosporogenezí. PCO analýza odrůd ukázala dva uzavřené klastery. Pouze u odrůdy Arabela byla zaznamenána větší odlišnost

A high-density consensus map of barley linking DArT markers to SSR, RFLP and STS loci and agricultural traits

BACKGROUND: Molecular marker technologies are undergoing a transition from largely serial assays measuring DNA fragment sizes to hybridization-based technologies with high multiplexing levels. Diversity Arrays Technology (DArT) is a hybridization-based technology that is increasingly being adopted by barley researchers. There is a need to integrate the information generated by DArT with previous data produced with gel-based marker technologies. The goal of this study was to build a high-density consensus linkage map from the combined datasets of ten populations, most of which were simultaneously typed with DArT and Simple Sequence Repeat (SSR), Restriction Enzyme Fragment Polymorphism (RFLP) and/or Sequence Tagged Site (STS) markers. RESULTS: The consensus map, built using a combination of JoinMap 3.0 software and several purpose-built perl scripts, comprised 2,935 loci (2,085 DArT, 850 other loci) and spanned 1,161 cM. It contained a total of 1,629 'bins' (unique loci), with an average inter-bin distance of 0.7 ± 1.0 cM (median = 0.3 cM). More than 98% of the map could be covered with a single DArT assay. The arrangement of loci was very similar to, and almost as optimal as, the arrangement of loci in component maps built for individual populations. The locus order of a synthetic map derived from merging the component maps without considering the segregation data was only slightly inferior. The distribution of loci along chromosomes indicated centromeric suppression of recombination in all chromosomes except 5H. DArT markers appeared to have a moderate tendency toward hypomethylated, gene-rich regions in distal chromosome areas. On the average, 14 ± 9 DArT loci were identified within 5 cM on either side of SSR, RFLP or STS loci previously identified as linked to agricultural traits. CONCLUSION: Our barley consensus map provides a framework for transferring genetic information between different marker systems and for deploying DArT markers in molecular breeding schemes. The study also highlights the need for improved software for building consensus maps from high-density segregation data of multiple populations

Transcriptional responses of winter barley to cold indicate nucleosome remodelling as a specific feature of crown tissues

We report a series of microarray-based comparisons of gene expression in the leaf and crown of the winter barley cultivar Luxor, following the exposure of young plants to various periods of low (above and below zero) temperatures. A transcriptomic analysis identified genes which were either expressed in both the leaf and crown, or specifically in one or the other. Among the former were genes responsible for calcium and abscisic acid signalling, polyamine synthesis, late embryogenesis abundant proteins and dehydrins. In the crown, the key organ for cereal overwintering, cold treatment induced transient changes in the transcription of nucleosome assembly genes, and especially H2A and HTA11, which have been implicated in cold sensing in Arabidopsis thaliana. In the leaf, various heat-shock proteins were induced. Differences in expression pattern between the crown and leaf were frequent for genes involved in certain pathways responsible for osmolyte production (sucrose and starch, raffinose, γ-aminobutyric acid metabolism), sugar signalling (trehalose metabolism) and secondary metabolism (lignin synthesis). The action of proteins with antifreeze activity, which were markedly induced during hardening, was demonstrated by a depression in the ice nucleation temperature

IDENTIFICATION OF OILSEED RAPE CULTIVARS USING AFLP MARKERS

A new type of molecular marker, fluorescence-based AFLP, was evaluated for its ability to identify oilseed rape cultivars. Each of the six tested AFLP combinations detected polymorphisms, the best combination (MCAA/ E-ACT) had 26% of polymorphic peaks from a total of 90 peaks and could distinguish analysed cultivars, and 4 out of 5 DH lines. The results presented here show that florescence-based AFLP was, for the purposes of oil seed rape cultivar fingerprinting, a very suitable approach

Analysis of the Genetic Structure of a Barley Collection Using DNA Diversity Array Technology (DArT)

Garlic (Allium sativum L.) is a vegetatively propagated species that has been used as a culinary and medic-inal plant and it is a source of sulphur-containing compounds. Our objectives are to assess S-alk(en)yl cysteine sulphoxide (SACS) content and to characterise genotypically, a set of 135 accessions, which have previously been assigned standard morphological descriptors. HPLC was used to assay the amount of sulphur-containing compounds, while AFLP was used as the genotyping platform. The 286 different informative AFLP fragments identified across the collection were subjected to principal component anal-ysis. Eight clusters were obtained: two consisted exclusively of A. sativum L. var. ophioscorodon clones; four clusters grouped together both non-bolting and semi-bolting clones (all classified as var. sativum); the remaining two contained only non-bolting types. AFLP genotyping successfully differentiated var. ophioscorodon from var. sativum clones. Semi-bolters were not distinguished from the non-bolting clones. A K-clustering analysis generated similar outcomes. However, a model-based approach identified some heterogeneity within bolting accessions. Strict correlation between the geographical origin of clones and the clusters to which they belonged was not observed. The SACS content, important for the taste and the protective health benefits of the bulbs, was analysed for the whole set. Clones of two non-bolting clusters contained significantly greater amounts of SACSs than the remaining ones. The non-bolter and semi-bolter clusters produced low amounts of SACS, so they are not locally adopted genotypes. This is the first report on variation between alliin:methiin ratio. The ratio varied between clusters too. The analysis of SACS content provided some insight into the genetic basis of this important end-use trait, and this can be further used for efficient conservation of garlic genotypes