• Pima Cotton Genetics

      Percy, R. G.; Silvertooth, Jeff (College of Agriculture, University of Arizona (Tucson, AZ), 1995-03)
      A short season feasibility study, using early maturing Pinta genotypes was conducted for a second season. Four early maturing genotypes, a short season check (P62) and a full season check variety (PS-7) were evaluated in replicated tests under short season and full season regimes. In both 1993 and 1994, most genotypes reached cutout around August 4, with 2759 accumulated heat units. All genotypes were earlier maturing than PS-7, as indicated by plant growth measurements and by sequential harvests. In 1994, the four early maturing experimental genotypes produced yields equal to or slightly better than the longer season cultivar PS-7. No differences in yield occurred between the short season and standard practice management systems in either year. A fiber improvement project was initiated in 1989 with the primary goals of increasing the fiber length and strength potential of Pima cotton. In 1989 the early maturing, short statured Pima strain P62 was crossed to Giza 45 and Giza 70 to transfer the fiber strength of those varieties into a heat tolerant, earlier maturing, productive Pima background. Likewise, P62 was crossed to the Sea Island cultivar St. Vincent V-135 with the objective of transferring the latter cultivar's long fiber length into an agronomic Pima background. Two resulting lines, one possessing high fiber strength and the other possessing high fiber length are planned for release in 1995-96.
    • Pima Cotton Improvement

      Moser, H. S.; Percy, R. G.; Ray, I. M.; Silvertooth, Jeff (College of Agriculture, University of Arizona (Tucson, AZ), 1995-03)
      The objective of this study was to evaluate the performance of five experimental lines (P73, P75, P76, P80, and P81) with two commercial varieties ('Pima S-6' and 'Pima S-79 of Pima cotton. All seven strains were grown in replicated strip tests at four locations across the Pima belt in 1994. While none of the experimental lines produced significantly more lint than the best Pima variety at any site, some of them possess traits that are valuable to Pima cotton breeders. P73 has long and strong fiber. P76 is a high yielding, early maturing line that produces long and strong fiber. P80's lint yields are similar to Pima S-7, but it is significantly earlier.
    • Pima Cotton Regional Variety Trial, Safford Agricultural Center, 1994

      Clark, L. J.; Carpenter, E. W.; Hart, G. L.; Nelson, J. M.; Silvertooth, Jeff (College of Agriculture, University of Arizona (Tucson, AZ), 1995-03)
      Ten long staple varieties (including two Pima experimental lines) were tested in a replicated small plot trial on the Safford Agricultural Center in Graham county at an elevation of 2950 feet. Even though the total number of heat units received during the season was nearly as high as the previous year, the average yield was nearly 300 pounds per acre lower. Olvey and Associates OA 304 was the highest yielding variety with a yield of 776 pounds per acre of lint and only two varieties broke the bale and a half mark. Yield and other agronomic data as well as fiber quality data are contained in this paper.
    • Pima Regional Variety Test; Maricopa Agricultural Center, 1994

      Hart, G. L.; Nelson, J. M.; Clark, L. J.; Silvertooth, Jeff (College of Agriculture, University of Arizona (Tucson, AZ), 1995-03)
      Nine Pima varieties and experimental strains were grown in a replicated trial at the Maricopa Agricultural Center. Lint yield, boll size, lint percent, plant population and fiber property data are presented in this report.