A genome-wide survey with different rapeseed ecotypes uncovers footprints of domestication and impro

• 作 者: WEI Dayong CUI Yixin HE Yajun XIONG Qing QIAN Lunwen TONG Chaobo LU Guangyuan DING Yijuan LI Jiana Christian Jung QIANWei
• 机 构: College of Agronomy and Biotechnology,Southwest University,Chongqing 400715,China
• 出 处: 2016年作物学全国博士生学术论坛
• 发表日期: 2016年5期

　　Rapeseed(Brassica napusL.)is one of the most important oilseed crops in the world.Despite a short time of domestication and improvement in rapeseed,it formed three diverse ecotype groups,spring,winter,and semi-winter.However,the genetic changes remained largely unknown among three ecotype groups.To detect selective signals,a set of 327 accessions from a worldwide collection were genotyped using a Brassicaarray,producing 33,186 high-quality SNPs.We found that the linkage disequilibrium(LD)was unevenly distributed across the genome,since approximately three quarters of weak and strong LD regions were located on the A and C subgenomes of B.napus,respectively.In total,202selective sweeps were identified across ecotype groups by calculating the nucleotide diversity andpopulation differentiation indices.They are spanning 4.75%(30.6Mb)of the genome.Within these genome regions,a number of known functional genes or loci were found to be in association with environmental adaptability and seed yield.In particular,we detected 14 SNPs located within selective sweeps which are in significant association with flowering time.These findings provide new insights into the structure of the B.napus genome and uncover the footprints of domestication and breeding.