• Comparison of Three Plant Growth Regulator Products on April Planted DPL 555BR Cotton, 2005

      Rethwisch, Michael D.; Swan, Ron; Luna, Manuel; Ramos, D. Michael; Wellman, Jessica; Tronstad, Russell; Norton, E. Randy (College of Agriculture, University of Arizona (Tucson, AZ), 2006-07)
      Three plant growth enhancement treatments were applied to April-planted DPL 555BR cotton on the morning of July 2, 2005. Plant parameter data were obtained during July, and yield and quality data were obtained at harvest in December. Usage of ChaperoneTM resulted in decreased potassium and phosphorus levels in petioles, as well as increased amounts of leaf chlorophyll. Treatments initially resulted in less fruiting structure/plant but had more than the untreated cotton at 26 days post treatment, with highest numbers per plant noted from the HappyGroTM + PhotoGro treatment. Each treatment resulted in less seed cotton and lint per acre than the untreated cotton. Less spotting associated with treated cotton increased the lint strength and increased trash levels. The AuxiGro® WP + CalMax® + Foliar Pride treatment resulted in the highest fiber strength per pound and lint value.
    • Interaction of Cotton Varieties and Rhizoctonia solani: Effects on Resultant Plant Populations, 2005

      Rethwisch, Michael D.; Reay, Mark; Turini, Thomas A.; Swan, Ron; Tronstad, Russell; Norton, E. Randy (College of Agriculture, University of Arizona (Tucson, AZ), 2006-07)
      Eight varieties were evaluated under field conditions for resultant plant populations after field infection with Rhizoctonia solani. Highest plant populations were noted in Delta and PineLand 454BR, followed by three other Delta and PineLand (DPL) varieties. Stoneville and Phytogen cotton varieties had reduced plant stands compared to DPL varieties at approximately 30 days after planting. DPL 454BR, which had the highest plant population, also had earlier growth and establishment than other varieties which is thought to have helped plant survival. Although all seed was treated with multiple fungicides, seed of DPL varieties was treated with several fungicide active ingredients (thiram, tridimenol) not present on seed from other varieties. Comparative increased stand on DPL varieties may be in part due to plant genetics as well as fungicide. Stand loss was noted in all varieties however. Data indicate that in-furrow application of fungicides or applications to small cotton plants may be necessary for heavier soils under cool and moist early season growing conditions in the low desert.