COTTON GERMPLASM ENHANCEMENT AND EVALUATION BY SSR MARKERS.

Plentiful cotton germplasm with variation traits including yield, fiber quality, and boll weight, lint percentage, resistant to disease, and insects, drought and salt ect. Were gained by use irradiation, transformation foreign DNAs and genes, multiple and interspecific crosses etc. Among them, 510 lines were identificated by using agronomic and economic trait and SSR molecular analysis. The results showed variation rate of different germplasm was significantly different, and diversity of different traits was also different. Multiple crosses combination with irradiation inducement, transformation foreign DNAs and genes etc. were best way to introduce external genetic resources, enhance and preserve the variation. Different exotic DNAs and genes were transferred into different Upland cotton by using pollen tube pathway transformation, and the transformation gene and DNA isogenic lines with significant variation of agronomic traits and molecular biological characters were obtained. Exotic genes and genetic diversity of SSR markers among 155 cotton introgressed lines from interspecific hybridization have been detected, and the results showed specific SSR loci were present among the interspecific lines with different exotic gene sources, and the more specific loci with exotic genes, the better the fiber quality, resistance to Verticillium wilt, tolerance of drought stress etc. This research also showed SSR molecular marker analysis techniques can be use for identification and evaluation of cotton germplasm effectively. [ABSTRACT FROM AUTHOR]