为定位芸薹种抗根肿病基因的连锁标记,利用芸薹种单一基因微卫星(UGMS)标记及基因组SSR和抗根肿病(clubroot resistance,CR)基因的紧密连锁分子标记,构建了结球白菜59-1×芜菁(CR)WJ04遗传连锁图谱,对芜菁WJ04和结球白菜59-1进行根肿病抗性鉴定和连锁位点分析。结果表明:抗根肿病芜菁自交系WJ04对来自我国根肿病主要疫区的4个根肿菌生理小种2、4、7和10均具有显性抗性,而59-1则均表现为感病。UGMS标记在大白菜和芜菁亚种间的多态性比率为30.1%,低于基因组SSR的50.8%;图谱覆盖长度为1 116.2cM,包含分布在10条连锁群的59个UGMS、72个基因组SSR和4个分别与CR基因Crr1、Crr2、Crr3和CRb连锁的标记。
To localize the previously developed unigene - derived microsatellite (UGMS) markers, genomic SSR markers and markers linked to the clubroot resistance (CR) loci in Brassica rapa, a genetic linkage map was constructed using a backcross population of Chinese cabbage 59 - 1 and CR turnip WJ04. Clubroot resistance test indicated that WJ04 had dominant resistance to four races of No. 2, 4,7 and 10 of Plasmordiam brassicase, while 59 - 1 was susceptible to all of the races. Localization results showed that the map contained 59 UGMS, 72 genomic SSR and 4 markers linked to 4 different CR loci, covering a genetic distance of 1 116cM of B. rapa genome. Four markers were linked to Crrl, Crr2, Crr3 and CRb genes respectively. Polymorphism frequency of UGMS markers was 30.1% between the two subspecies of Chinese cabbage and turnip, which was lower than that of the genomic SSR (50.8%).