Targeted transfer of trait for Verticillium wilt resistance from Gossypium barbadense into G.hirsutum using SSR markers

Verticillium wilt (VW) is a soil-borne disease of cotton that is destructive worldwide. Transferring desired traits from Gossypium barbadense is challenging through traditional interspecific introgression. We previously demonstrated that a molecular marker, BNL3255-208, is associated with VW resistance in G.barbadense. This breakthrough opens the way for marker-assisted selection (MAS) breeding. Here, the highly resistant G.barbadense cv. Pima90-53' and the severe diseased Gossypium hirsutum cv. CCRI8' were used as donor parent and recipient parent, respectively. Our goal was to transfer the disease resistance from donor to recipient via MAS. Among 71 MAS obtained lines, as many as 19 lines had enhanced resistance. Among those lines, 11 lines showed high resistance and four lines displayed resistance to VW. Moreover, seven lines displayed improved fibre quality. After combining the markedly improved resistance and fibre properties, we identified two elite innovated introgression lines - ZY2 and ZY31 - that did not seem to differ in other agronomic traits from the recipient parent. This study first successfully transferred of G.barbadense resistance into G.hirsutum by MAS.