Working group session:
Germplasm and Genetic Stocks
Presentation type:
poster
Authors:
Saha, Sukumar; Wu, Jixiang ; Norton Jenkins , Johnie; Crane McCarty , Jack; Todd Campbell , Benjamin; W Hayes , Russell; A. Raska, Dwaine; Gore, Michael; Ulloa, Mauricio; J Burke , John; M. Stelly, David
Presenter:
Saha, Sukumar
Correspondent:
Saha, Sukumar
Abstract:
Cotton is facing some serious challenges in the global market from the competition of synthetic fibers. Genetic solutions to this challenge require adequate genetic variation to be present in the breeding germplasm.The exotic gene pools in wild and unadapted species holds the promise of unlocking many potentially valuable genes/alleles in the genetic improvement of Upland cotton (Gossypium hirsutum L.). However, the potential utility and value of specific alien genes is usually compromised by co-inheritance of closely linked genes that have deleterious effects on productivity in conventional method of interspecific crosses. To physically separate the beneficial alien genes from undesirable ones by breeding can thus be extremely difficult in interspecific introgression to improve Upland cultivars. A potentially complementary approach of conventional breeding method is to use chromosome or chromosome segment substitution (CS) lines from alien species. The objective of this paper is to provide a summarized report on the concept, development and utilization of CS lines from G . barbadense, G. tomentosum and G. mustelinum in the genetic analysis and germplasm improvement of Upland cotton. In each CS line, a pair of chromosomes (or chromosome arm-specific segments) of G. hirsutum inbred TM-1 was replaced by the respective pair from the alien species. We also developed chromosome specific recombinant inbred line (CS-RIL) from crosses of a CS line with their common recurrent parent, inbred TM-1. An individual plant of the F2 population from this cross was maintained by selfing via single seed decent method until F6 generation in CS-RIL development. The comparative analysis of such unique genetic materials detected the genetic effects of novel alleles by specific alien chromosome/segment associated with the quantitative traits of importance. This research demonstrated a new strategy to complement conventional interspecific introgression using a novel method of chromosome shuffling among the alien and domesticated species. This study helped in the development of a unique set of germplasm by targeted introgression of desirable genes from wild and unadapted types into genetic backgrounds with reduced linkage drag effects, readily useable by the cotton breeders. Comparative analysis of fiber traits on a chromosome-by-chromosome basis provided new information of valuable genes and some cryptic alleles of alien species that can be useful for the genetic improvement of Upland cotton.