Detection of QTL for Verticillium wilt resistance in upland cotton

Upland cotton Sukang045,resistant to Verticillium wilt,and the susceptible variety,Suyan116,were used as parental materials to develop a tagging population with 237 F2 individual plants.By inoculating pathogenic fungus strain BP2 to the populations of P1,P2,F1,F2 ∶ 3,the relative disease indexes of each generation were scored.A total of2 400 pairs of SSR primers were screened,and 78 were polymorphic.Using Join Map software,a genetic linkage map of intraspecific F2 populations was constructed.The linkage map was comprised of 41 loci on 15 linkage groups,covering359.90 c M and approximately 7.2% of the total cotton genome.One resistance QTL was detected and localized in the interval of NAU2970 and MUSS138,responsible for 9.69% phenotypic variance in F2 ∶ 3.