玉米抗纹枯病QTL定位

QTL Mapping of Resistance to Banded Leaf and Sheath Blight in Maize

为明确玉米对纹枯病的抗病机制,以玉米自交系CML429(抗)×DM9(感)的182个F2单株为作图群体,构建了包含82个SSR标记位点的遗传连锁图谱,覆盖玉米基因组的1530.9cM,标记间平均图距为18.67cM。通过人工接种分析F2:3群体对纹枯病病菌的抗性表现,用复合区间作图法分析抗病QTL及遗传效应,共检测到4个抗性QTLs,分布于第6、7和10条染色体上,在第6染色体上检测到2个QTLs,分别与标记bnlg107、umc1796连锁,其遗传效应分别能解释表型方差的12.63%和0.27%;在第7、10染色体上各检测出1个QTL,分别与标记bnlg1161、phi059连锁,其遗传效应能分别能解释表型方差的15.21%和5.42%。

In order to realize the mechanism of resistance for maize to banded leaf-sheath blight （BLSB）. The genetic linkage maps was construtted with 82 SSR markers based on a maize population consisting of 182 F2 individuals from cross CML429 （resistant） ×DM9 （ susceptible）, covering 1530.9cM on total ten chromosomes with an average interval length of 18.67cM. The population of 182 F2：3 lines was evaluated for BLSB resistance under artificial ineculation. Then we analyzed QTLs conferring resistance to BLSB with the strategy of composite interval mapping （CIM）. The results showed four QTLs for resistance to BLSB distributing on chromosomes 6, 7 and 10 respectively. Two QTLs which were linked to markers bnlg107 and umc1796 were detected on chromosome 6. They could account for 12.63 % and 0. 27 % of the phenotypic variance respectively. Two QTLs for disease incidence, linked with markers bnlg1161 and phi059, were identified on chromosomes 7 and 10, which could explain 15.21% and 5.42 % of the phenotypie variance respectively.