Evaluation of Chromosome Specific RI Lines for Improved Fiber Traits

Breeders have long aspired to combine the best attributes of G. hirsutum and G. barbadense, but have had limited success because of the biological and technical challenges associated with the conventional methods of interspecific introgression.  Recently we have released a set of chromosome substitution lines where individual chromosomes or chromosome arms of G. barbadense have been substituted into G. hirsutum (CS-B lines) We have developed two sets of chromosome specific recombinant inbred lines (RI) from the cross of TM-1 with CS-B5sh and CS-B17 respectively.  Results from the field evaluation of about 50 RI lines specific to CS-B5sh and CS-B17 respectively will be presented in the meeting.  Results from this study highlight the vital importance of epistasis in fiber quality traits, the diversity in fiber traits within each set of RI lines and the novel effects of some cryptic beneficial alleles affecting fiber traits on the 3-79 chromosomes, whose effects were not detected in the 3-79 parental lines.