• Pima Cotton Genetics

      Percy, R. G.; Turcotte, E. L.; Silvertooth, Jeff; Bantlin, Marguerite (College of Agriculture, University of Arizona (Tucson, AZ), 1991)
      An isozyme study of the diversity and structure of Goss_vpium nii revealed levels of genetic variation within the species which were high for an island endemic. Infraspecific diversity of G. darwinii was observed among populations of the various Galapagos Islands. Evidence of introgression of other Gossypium species into darwinii was noted. An investigation into the effects of altered Pima (G. barbadense) fiber genotypes on interspecific hybrid fiber characteristics indicated that parent genotype could significantly affect hybrid fiber length, strength, uniformity, and micronaire. However, hybrid heterosis for fiber length and micronaire greatly exceeded the influence of parent genotype. Hybrid fiber characteristics were unique, fitting within neither the extra -long staple nor long staple classifications. A conversion program to convert photoperiodic short-day accessions of a Gossvpium barbadense germplasm collection to day neutrality continues.
    • Pima Cotton Improvement

      Turcotte, E. L.; Percy, R. G.; Silvertooth, Jeff; Bantlin, Marguerite (College of Agriculture, University of Arizona (Tucson, AZ), 1991)
      Pima experimental strains P67, P69, P71, P73, P74, and Pima S -6 were grown in Regional tests at 11 locations across the Pima belt in 1990. P73 averaged highest in mean yield across locations followed by P74, P69, P67, Pima S-4 and P71. The experimental strains, in comparison with Pima S-6, had longer, stronger, finer, and more whitish fiber. Experimental strains P45, PSI, P53, P62, P66, and EIS were released jointly by the USDA ARS and the Arizona Agricultural Experimental Station, and registered in Crop Science.