大豆种粒斑驳抗性的遗传分析及基因定位

运用SSR标记技术及分离群体组群分析法(BSA法), 对大豆品系3C624×东农8143的F₂、F₃代群体接种SMV1号株系鉴定种粒斑驳抗性, 并进行抗种粒斑驳基因的分子定位。结果表明, 东农8143对SMV1号株系的种粒斑驳抗性受1对显性基因控制。用Mapmaker/Exp 3.0b进行连锁分析, 抗种粒斑驳基因位于大豆染色体组的F连锁群上, 并获得了与抗种粒斑驳基因紧密连锁的5个SSR标记Sat_297、Sat_229、Sat_317、Satt335和Sct_188, 标记与抗病基因间的排列顺序和连锁距离为Sat_297–12.4 cM–Sat_229–3.6 cM–SRSMV1–1.7 cM–Sat_317–2.4 cM– Satt335–13.8 cM–Sct_188。其中近距离标记Sat_229(3.6 cM)、Sat_317(1.7 cM)和Satt335(4.1 cM)可用于标记辅助选择育种和抗源筛选。

Genetic Analysis and Mapping of Resistance Gene to Seed Coat Mottle in S oybean

Soybean mosaic virus (SMV) causes a worldwide disease in soybean, reducing yield and making mottling of soybean seeds, and so largely losing soybean economy value. Resistant variety breeding is the most effective way to protect against the seed coat mottle. In this study, an F_2:3 population, derived from Dongnong 3C624 (susceptible) × Dongnong 8143 (resistant), was used to study the genetic mechanism of the resistance, and map the resistant gene of seed coat mottle by simple sequence repeat (SSR) markers with bulked segregation analysis (BSA) method. Two parents and their F₂, F₃ population were inoculated with SMV strain No.1 in 2006 and 2007. Identification results in two years showed that resistance to SMV strain No.1 of Dongnong 8143 was controlled by one pair of dominant genes. Six hundred pairs of SSR primers were screened, and five SSR markers, Sat_297, Sat_229, Sat_317, Satt335, and Sct_188, were mapped near the resistance gene. Linkage analysis indicated that the resistance gene locus was located on the linkage group F. The order and genetic distance among the resistance gene and markers were Sat_297–12.4 cM–Sat_229–3.6 cM–SRSMV1–1.7 cM–Sat_317–2.4 cM–Satt335–13.8 cM–Sct_188. Sat_229, Sat_317, and Satt335 can be used for molecular assisted breeding.