Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành y học dành cho các bạn tham khảo đề tài: Origins of the amphiploid species Brassica napus L. investigated by chloroplast and nuclear molecular markers | Allender and King BMC Plant Biology 2010 10 54 http 1471-2229 10 54 BMC Plant Biology RESEARCH ARTICLE _ Open Access Origins of the amphiploid species Brassica napus L. investigated by chloroplast and nuclear molecular markers Charlotte J Allender 1 and Graham J King2 Abstract Background The amphiploid species Brassica napus oilseed rape Canola is a globally important oil crop yielding food biofuels and industrial compounds such as lubricants and surfactants. Identification of the likely ancestors of each of the two genomes designated A and C found in B. napus would facilitate incorporation of novel alleles from the wider Brassica genepool in oilseed rape crop genetic improvement programmes. Knowledge of the closest extant relatives of the genotypes involved in the initial formation of B. napus would also allow further investigation of the genetic factors required for the formation of a stable amphiploid and permit the more efficient creation of fully fertile re-synthesised B. napus. We have used a combination of chloroplast and nuclear genetic markers to investigate the closest extant relatives of the original maternal progenitors of B. napus. This was based on a comprehensive sampling of the relevant genepools including 83 accessions of A genome B. rapa L. both wild and cultivated types 94 accessions of B. napus and 181 accessions of C genome wild and cultivated B. oleracea L. and related species. Results Three chloroplast haplotypes occurred in B. napus. The most prevalent haplotype found in 79 of accessions was not present within the C genome accessions but was found at low frequencies in B. rapa. Chloroplast haplotypes characteristic of B. napus were found in a small number of wild and weedy B. rapa populations and also in two accessions of cultivated B. rapa brocoletto . Whilst introgression of the B. napus chloroplast type in the wild and weedy B. rapa populations has been proposed by other studies the presence of this haplotype within
