• 1985 Nutsedge Control Trials

      Heathman, Stanley (College of Agriculture, University of Arizona (Tucson, AZ), 1986-03)
    • Analysis of F₃ Date of the Ob₁ᵈY₁ᵈ Linkage Group

      Endrizzi, J. E.; Sherman, R.; Department of Plant Sciences (College of Agriculture, University of Arizona (Tucson, AZ), 1986-03)
    • Analysis of Progeny 24" + il" (ISO14S) for the Recovery of Monosomic 14

      Endrizzi, J. E.; Sherman, R.; Department of Plant Sciences (College of Agriculture, University of Arizona (Tucson, AZ), 1986-03)
    • Application of Herbicides in Cotton Through Gravity Flow Furrow Irrigation

      Chernicky, J. P.; Hamilton, K. C. (College of Agriculture, University of Arizona (Tucson, AZ), 1986-03)
      The objective of this experiment was to evaluate the potential of applying herbicides in the irrigation water during a furrow irrigation as an alternate method of herbicide application in cotton. Further research is needed to study this method of applying herbicides. If a program could be designed for the Arizona cotton grower, it would help reduce production costs. However before this method can be recommended the environmental impact of such a treatment must be investigated to prevent jeopardizing currently labelled herbicides in cotton.
    • Changes in the Hormonal Status of Young Bolls and Their Abscission Zones in Relation to Boll Retention

      Guinn, Gene; Brummett, D. L.; Western Cotton Research Lab (College of Agriculture, University of Arizona (Tucson, AZ), 1986-03)
      An experiment was conducted to test the hypothesis that a nutritional stress (shortage of photosynthate) affects the hormonal balance in bolls and their abscission zones. It did. The concentration of indoleacetic acid (IAA) in abscission zones of young bolls decreased and boll shedding increased as competition for photosynthate increased. Water deficit also decreased the IAA content of young bolls and their abscission zones, but greatly increased the concentration of abscisic acid (ABA) a hormone that may increase boll shedding.
    • Chemical Hybridizing Program (Chembred™)

      Olvey, James M.; Ball, Suzanne; Greenley, Barbara; McAlister, Adele; Savoy, Bryan; Wessel, Douglas (College of Agriculture, University of Arizona (Tucson, AZ), 1986-03)
      Since discovering a Chemical Hybridizing Agent (CHA) for cotton in 1978, we have perfected the technique of utilizing this breeding tool as well as determining the potential of hybrids in a breeding program.
    • Comparative Trap Catches in Four Boll Weevil Trap Types

      Meng, T. Jr.; Bariola, L. A.; Henneberry, T. J.; Western Cotton Research Center (College of Agriculture, University of Arizona (Tucson, AZ), 1986-03)
      Four trap types were used to trap boll weevils at 1 m heights, with and without grandlure, and 2 trap types were compared at 0.5 m height, with and without grandlure. The results indicate trap height may be an important factor in boll weevil catches at certain times during the cotton season. Also trap color, design and other factors may influence trap catches since traps not baited with grandlure caught high numbers of boll weevils during certain times during the cotton growing season.
    • A Comparison of Selected Cotton Hedges for Arizona Cotton Producers

      Torok, S. J.; Beach, W. E.; Department of Agricultural Economics, The University of Wyoming; Arizona State University (College of Agriculture, University of Arizona (Tucson, AZ), 1986-03)
      Cotton options on futures began trading in the fall of 1984 offering Arizona cotton producers an alternative risk management tool. Advantages of hedging with cotton options include: limiting risk, preserving unlimited profit potential, providing increased marketing flexibility and greater liquidity. This study compared selected cotton option hedges utilizing mean net revenues and standard deviations. Also, computed premiums were calculated with a modified Black-Scholes option pricing model to identify a historical price volatility that consistently signaled favorable cotton option trades.
    • Comparison of Three and Four Bract Squares on Several Deltapine Cultivars

      Terry, Irene (College of Agriculture, University of Arizona (Tucson, AZ), 1986-03)
      The number of three and four bract squares on several currently used Deltapine cultivars were observed during the early squaring period in plots untreated and treated for early season insect control. The percent of four bract healthy squares counted in June were higher in Deltapine 41 than several other varieties including Deltapine 90. The percent of four bracts between treated and untreated plots were significantly different in only two out of 5 locations. In another test where both DP 90 and DP 61 were compared for total healthy plus shed squares, DP 90 and DP 61 were equal on several dates in their proportion of three and four bract squares.
    • Cotton Forward Contracting Performance in 1980-84

      Firch, Robert S. (College of Agriculture, University of Arizona (Tucson, AZ), 1986-03)
    • Cotton Variety Observation, Safford Agricultural Center

      Clark, Lee J.; Thatcher, L. Max (College of Agriculture, University of Arizona (Tucson, AZ), 1986-03)
    • Cotton Variety Trials, Greenlee County

      Brown, Mike; Lunt, Mike; DeRosa, Edith; Clark, Lee J. (College of Agriculture, University of Arizona (Tucson, AZ), 1986-03)
    • Cytogenetic Analysis of Lf Marker Gene and Monotelodisome 12L

      Endrizzi, J. E.; Sherman, R.; Department of Plant Sciences (College of Agriculture, University of Arizona (Tucson, AZ), 1986-03)
    • Early Insect Control in Cotton, Greenlee County

      Tyler, Ray; DeRosa, Edith; Clark, Lee J.; Moore, Leon (College of Agriculture, University of Arizona (Tucson, AZ), 1986-03)
      Cotton was treated at the pinhead square stage with Orthene to prevent boll shed caused by thrips and Lygus. Yield results showed no statistically significant differences, even though yield trends indicated a decrease in the treated plots compared to the check. Severe pressure from Heliothus later in the season and the yield trends would indicate that the insecticide treatment effect on the beneficial insects was more important than its effect on thrips and Lygus.
    • Early Postemergence Control of Purple Nutsedge in Cototn Moore Farms, Waddell

      Heathman, Stanley; Chernicky, Jon; Farr, Charles (College of Agriculture, University of Arizona (Tucson, AZ), 1986-03)
    • Early Season Insect Control: Effects on Cotton Variety Yield and Fruiting

      Terry, Irene; Barstow, Ben; Arizona Cooperative Extension Service (College of Agriculture, University of Arizona (Tucson, AZ), 1986-03)
      Many cotton field trials were conducted in central Arizona to compare various early season pesticide treatments on several commercially available cultivars for plant growth responses and thrips control. Treated plots received either aldicarb (Temik), at planting or first square, or acephate (Orthene), one to three foliar applications during early squaring. Although results were quite variable, general trends included: most treatments did reduce thrips populations; fewer shed squares occurred in plots treated at first square; plants compensated for this square shed; treated plots may be earlier in boll production than untreated areas; and most tests showed no statistical differences in healthy square production or in yield.
    • Effect of CO₂ on Cotton Yile and Water Use

      Kimball, B. A.; Mauney, J. R.; Nakayama, F. S.; U. S. Water Conservation Laboratory; Western Cotton Research Laboratory (College of Agriculture, University of Arizona (Tucson, AZ), 1986-03)
      Seed cotton yields were increased an average 80% by a near doubling of the carbon dioxide concentration (approximately 650 ppm) in 3 years of experiments using CO₂-enriched, open-top chambers on field-grown cotton. Water use was not changed much or in a consistent direction, so water use efficiency increased in step with the dramatic yield increase.
    • The Effect of Low Quality Seed on Lint Yields

      Hofmann, Wallace C.; Kittock, David L. (College of Agriculture, University of Arizona (Tucson, AZ), 1986-03)
      Comparison of 23 low quality upland cotton seed lots with high quality lots in 19 tests over 4 years showed consistent lint yield reduction from low quality seed. The low quality seed lots produced an average of 226 pounds less lint/acre than high quality seed. At $0.60/pound of lint that is $135.37/acre. By analysis of covariance, which adjusted lint yield for equal stand, poor stand explained 162 pounds of lint loss ($97.20/acre) and apparent reduced seedling vigor accounted for 64 pounds of lint loss or $38.16/acre.
    • Effect of Nitrogen Fertilizer Application on Cotton Yields, Safford Agricultural Center

      Clark, Lee J.; Gardner, Bryant R. (College of Agriculture, University of Arizona (Tucson, AZ), 1986-03)
      A soil depleted of nitrogen by cropping with Sudan grass and removing all the residues was planted to Upland (DP 90) and Pima (S-6) cotton. Nitrogen was added in the form of urea at three different stages of plant growth, applying a total of 0, 50 or 100 pounds of nitrogen. The yield of lint from DP 90 was increased where nitrogen was added; however, there were no differences in yield with the timing nor total amount of nitrogen added. In the case of S-6, fertilizer nitrogen did not increase yield.
    • Effect of PIX on Cotton Varieties Over Two Years, Graham County

      Layton, Dennis; Cluff, Ron; Clark, Lee J.; Cramer, Gary (College of Agriculture, University of Arizona (Tucson, AZ), 1986-03)
      PIX was applied on 6 varieties of cotton in 1984 and on 4 varieties in 1985. Application rates of 1/2 pt/ac, a split application of 1/2 pt + 1/2 pt and a single application of 1 pt/ac were evaluated. Different varieties were affected differently, but yield was depressed on all varieties by the split rate in 1984 and increased on all varieties by the single application of 1 pt/ac in 1985. Plant heights were reduced by all applications.