棉 花 学 报 Cotton Science 2006，18(5)：269-272
A SSR Marker Linked with the Gene of Verticillium Wilt Resistance in Gossypium barbadense Abstract：One hundred and eighty-two F2 individuals from the cross between the susceptible Gossypium hirsutum CCRI 8 and the resistant G. barbadense Pima 90-53 were exploited to detect the SSR molecular marker linked with gene of Verticillium wilt resistance. Each F2 individual descended its F2：3 line through self crossing. The resistance of the F2 individuals was determined in the field disease nursery. All of the F2：3 lines were tested in the growth chamber to verify the resistance of the relevant F2 individuals. The results showed that 140 F2 plants were resistant and 42 F2 plants susceptible. The ratio of F2 resistant plants and the susceptible was 3∶1，and it accorded with the χ2c test. Genomic DNAs of all plants were extracted by CTAB method. Based on the resistance of F2 plants，10 resistant and 10 susceptible plants' DNAs were chosen to make up of the resistant and susceptible gene pools，respectively. Seven hundred and sixty-eight pairs of SSR primers were screened using the gene pools. Out of these primers，BNL2440 and BNL3255 showed polymorphic between resistant and susceptible DNA pools，and the parents also had the same polymorphic markers on the same locus. The polymorphic marker amplified by BNL2440 did not link with the resistance gene. A polymorphic fragment of 208bp amplified by BNL3255 primer was designated as BNL3255-208. It was found that the genetic distance between the locus of Verticillium wilt resistance and BNL3255-208 marker was 13.7cM when calculated by Mapmaker/Exp (Version3.0b) software. BNL3255 marker was located on the short arm of No. 5 chromosome (c5sh). It can be used in marker assisted selection (MAS) of breeding resistant varieties and lay a foundation for cloning resistance genes.
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