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A Diversity Arrays Technology (DArT) marker system was applied for the first time to common beans ( Phaseolus vulgaris L.) and tested on 89 accessions from the IAC and CIAT common bean breeding programs, as well as on landraces from the FAO collection. Seven frequently used restriction endonucleases were tested in combination with a rare-cutting restriction enzyme, PstI, to evaluate their suitability for DArT technology. Two restriction enzyme combinations ( PstI/ BstNI and PstI/ TaqI) were selected to evaluate polymorphisms and PstI/ BstNI, which yielded the most polymorphisms, was used to construct the final array. Genotyping was done by labelling the genomic representations with the fluorescent nucleotides cy3-dUTP and cy5-dUTP. The poly-linker fragment was labelled with 6-FAM and used as a control treatment and standard to determine the amount of DNA spotted on the array for each clone. DArTsoft version 7.3 software was used to analyse, identify and score polymorphic markers. Arrays containing individual fragments from these representations generated DArT fingerprints with a genotype call rate of 97.1% and a scoring reproducibility of at least 99.9%. A total of 2,501 polymorphic markers were found. Neighbour-joining distance matrices were used to create dispersion graphs that distinguished the two major gene pools of common beans and classified the accessions as either Andean or Mesoamerican. A principal coordinate analysis of the DArT marker results explained 82% of the total data variation. These results show that the DArT platform was accurate for studying the genetic diversity of the common bean and efficient for the large-scale detection of polymorphisms. These properties make marker technology a choice for future experiments. This is the first report to describe the use of DArT technology for genotyping the common bean. [ABSTRACT FROM AUTHOR]

We developed Diversity Array Technology (DArT) markers for application in genetic studies of Brassica napus and other Brassica species with A or C genomes. Genomic representation from 107 diverse genotypes of B. napus L. var. oleifera (rapeseed, AACC genomes) and B. rapa (AA genome) was used to develop a DArT array comprising 11 520 clones generated using PstI/BanII and PstI/BstN1 complexity reduction methods. In total, 1547 polymorphic DArT markers of high technical quality were identified and used to assess molecular diversity among 89 accessions of B. napus, B. rapa, B. juncea, and B. carinata collected from different parts of the world. Hierarchical cluster and principal component analyses based on genetic distance matrices identified distinct populations clustering mainly according to their origin/pedigrees. DArT markers were also mapped in a new doubled haploid population comprising 131 lines from a cross between spring rapeseed lines ‘Lynx-037DH’ and ‘Monty-028DH’. Linkage groups were assigned on the basis of previously mapped simple sequence repeat (SSRs), intron polymorphism (IP), and gene-based markers. The map consisted of 437 DArT, 135 SSR, 6 IP, and 6 gene-based markers and spanned 2288 cM. Our results demonstrate that DArT markers are suitable for genetic diversity analysis and linkage map construction in rapeseed. [ABSTRACT FROM PUBLISHER]