Evaluation of the introgressed lines and screening for elite germplasm in Gossypium

In this research, 155 cotton introgressed lines from interspecific hybridization have been collected for the purpose of evaluating the effects of enhancement of new upland cotton germplasm by interspecific hybridization, screening for elite germplasm and improving cotton breeding. Through identification of various agricultural traits, we found that different wild cotton species had different capacities in terms of fiber quality, disease resistance, tolerance of abiotic stress, pest resistance and so on. SSR molecular marker technology has been used to detect the exotic genetic elements in interspecific hybrids, and 25 SSR specific loci that can be classified into two groups were found among 15 pairs of SSR primers. Results also showed that 8 exotic germplasm (Gossypium barbadense, G. arboreum and G. thurberi, etc) had genetic transmission toward upland cotton. A strategy of screening elite germplasm with exotic genes based on the molecular marker-assisted breeding techniques was suggested, and 18 lines with high-quality fiber and 4 lines with resistance to Fusanrium wilt and Verticillium wilt have been obtained.