• 2004 Low Desert Upland Cotton Advanced Strains Testing Program

      Husman, S.; White, K.; Tronstad, Russell; Husman, Steve; Norton, Randy; University of Arizona Cooperative Extension (College of Agriculture, University of Arizona (Tucson, AZ), 2005-05)
      Upland cotton advanced strains and commercial check varieties were evaluated in replicated field studies at three locations in 2004. The test sites include the AZ locations of Safford, Maricopa, and Yuma. Eight seed companies submitted a maximum of ten advanced strain entries per location. Three commercial check varieties were used at all three sites, and included ST5599BR, DP449BR, and DP448B. Data collected included final plant heights, yield, and fiber quality. The research is conducted in order to develop public unbiased performance data of genetic materials that have moved to the advanced stages of testing and are being considered for commercial release. The data have historically been used to add to seed company databases and assist with commercial release decisions.
    • Arizona Upland Cotton Variety Testing Program, 2004

      Husman, S.; Norton, R.; Norton, E.; Clay, P.; Zerkoune, M.; White, K.; Tronstad, Russell; Husman, Steve; Norton, Randy; University of Arizona Cooperative Extension (College of Agriculture, University of Arizona (Tucson, AZ), 2005-05)
      Each year the University of Arizona conducts variety trials across the state to evaluate the performance of upland cotton varieties. These tests provide unbiased data on the performance of varieties when tested side-by-side under typical production practices. In 2004 we planted a total of 11 trials, two in the Yuma region (Yuma County), two in the western region (LaPaz and Mohave counties), four in the central region (Maricopa and Pinal counties), one in the southern region (Pima county), and two in the eastern region (Graham and Cochise counties). We tested seven to eight commercially available varieties at each test site.
    • Evaluation of Irrigation Termination Effects on Yield and Fiber Quality of Upland Cotton, 2004

      Silvertooth, J. C.; Galadima, A.; Tronstad, R.; Tronstad, Russell; Husman, Steve; Norton, Randy; University of Arizona Cooperative Extension (College of Agriculture, University of Arizona (Tucson, AZ), 2005-05)
      A field experiment was conducted in 2004 at the University of Arizona Maricopa Agricultural Center (1,175ft. elevation) to evaluate the effects of five irrigation termination (IT1, IT2, IT3, IT4, and IT5) dates on yield and fiber micronaire of several Upland cotton varieties. In addition, the economic relationships of IT treatments were also evaluated. The first IT treatment (IT1) was made with the intention of terminating irrigations somewhat pre-maturely. Based upon current UA recommendations for IT to complete a single cycle fruit set, the more optimal date of IT would have included one or two additional irrigations (beyond IT1). In this experiment, IT2 was structured to provide an additional (one) irrigation before the more optimal date. For the IT3 plots, the intention was to attempt to time termination to match the conventional growers optimal date. The IT4 and IT5 were imposed to attempt to produce a second cycle fruit set and irrigations continued until 27 August and 21 September respectively. In general, lint yield and micronaire results revealed significant differences among the IT treatments. In a similar fashion to 2000-2002 IT experiments, micronaire and lint yield values consistently increased with later IT dates. The best micronaire and lint yield results were achieved with IT4 date, which received 12 in. less irrigation water than IT5. The 12 in. water saved equates to approximately 20% of the total water used under the conventional practice. The average marginal value of water for all Upland varieties in going from IT1 to IT2, IT2 to IT3, IT3 to IT4, and IT4 to IT5 using November 2004 prices and low carrying costs is calculated at $320.07, $150.15, $100.54, and -$28.16 per acre-foot of water. If steeper mike discounts (November 1999), a lower base lint price (45¢/lb.), and higher costs (i.e., more costly insecticide and chemical costs) are imputed to extend the crop, the marginal value of an acre-foot of water for all Upland varieties and replications in going from IT1 to IT2, IT2 to IT3, IT3 to IT4, and IT4 to IT5 is estimated at $164.04, $48.15, $12.97, and -$94.79. Profitability and marginal value of water sometimes vary quite markedly between different varieties and termination dates as well.
    • Twin Line Cotton Production in a Conservation Tillage System

      Husman, S.; Clay, P.; Taylor, E.; White, K.; Tronstad, Russell; Husman, Steve; Norton, Randy; University of Arizona Cooperative Extension (College of Agriculture, University of Arizona (Tucson, AZ), 2005-05)
      Two experiments were conducted in 2004 evaluating twin line cotton production using a conservation tillage system approach. DPL 451 BR Upland cotton was planted into oat hay stubble on April 30 and May 5, 2004 at commercial cooperator sites at Tonopah and Tolleson AZ, respectively. The two primary experimental objectives were to determine whether cotton planted into previous crop residue initiated fruiting on the mainstem once the cotton seedling grew above the crop stubble and whether there were differences in lint yield between the single and twin line system. Previous twin line cotton production research had been conducted by authors at 30 locations from 2001-2003. In almost all cases, the harvest of low set bolls presented problems with the twin line system. In 2004, the initiation of the first fruiting branch was independent of the stubble height at both locations. In addition, there were no differences in lint yield in either a single or twin line cotton production system when planting into previous crop residue using conservation tillage.