• Variety/Date of Planting Test

      Pegelow, E. J. Jr. (College of Agriculture, University of Arizona (Tucson, AZ), 1988-03)
      Three upland cotton varieties (Stoneville 506, Deltapine 20, and Centennial) were planted on four dates in 1987 at the Maricopa Agricultural Center and observed for flowering, boll opening, and lint yield. Results from 1985-1987 are being used to develop heat unit models for the timing of these events.
    • The Effect of Soil Temperature and Inoculum Levels of Thielaviopsis basicola on Black Root Rot of Cotton

      Hine, R. B.; Mauk, P. A.; Tedla, Tesfaye (College of Agriculture, University of Arizona (Tucson, AZ), 1988-03)
      Two planting dates, March 28, and April 28 were used to study the effect of soil temperature during planting on black root rot of cotton. Also, several cotton varieties were evaluated for response to the disease under varying soil temperatures and inoculum levels.
    • Pima Cotton Genetics

      Percy, R. G.; Turcotte, E. L. (College of Agriculture, University of Arizona (Tucson, AZ), 1988-03)
      Maintenance and evaluation of a collection of primitive Gossypium barbadense L. cottons progressed in 1987. Conversion of the non flowering tropical cottons to a flowering, day- neutral habit progressed. So did efforts to incorporate potentially useful biological and environmental stress tolerant traits into agronomic Pima backgrounds. Six cottons of the primitive cotton collection were found to potentially possess bacterial blight resistance. Genetic populations were developed to investigate the inheritance and distribution of two mutant marker traits in cotton. Interspecific Fl hybrid populations were developed for evaluation in 1988.
    • Purple Nutsedge Control in Fallow Soil, Woodhouse Farm - Roll

      Heathman, Stanley; Chernicky, Jon; Howell, Don; Tickes, Barry (College of Agriculture, University of Arizona (Tucson, AZ), 1988-03)
    • Weather Conditions Associated with the Development of Southwestern Rust on Cotton

      Young, Deborah; Brown, Paul (College of Agriculture, University of Arizona (Tucson, AZ), 1988-03)
      Weather conditions leading to the development of southwestern rust on cotton were evaluated at 3 locations in southeastern Arizona. Rust appeared following an extended period of wet, humid weather. In excess of 16 hours of wet canopy/high humidity conditions were observed on two consecutive days between 5 and 7 days prior to the appearance of rust. Temperatures during the wet canopy/high humidity periods were moderate, ranging from 65 F to 76 F. Afternoon rain showers initiated these extended periods of wet canopy /high humidity conditions.
    • Short Staple Variety Demonstration, Graham County

      Clark, Lee J.; Cluff, Ronald E. (College of Agriculture, University of Arizona (Tucson, AZ), 1988-03)
      Two short staple variety trials were held in Graham county, one toward the west end of the valley (Eden), and one in the center of the valley (Thatcher), both with 15 varieties. Delta Pine 90 was the highest yielding variety at both locations, with yields of 1,386 pounds of lint per acre at Thatcher and 1,123 pounds at Eden. Two new varieties, Northrup King 111 and BR 110, show some promise in the area, with yields close to that of Delta Pine 90. Lint quality and grade are listed for each variety.
    • Response of Texas Root Rot to a Soil Sterilant in Graham County, Part II, 1987

      Clark, Lee J.; Cluff, Ronald E. (College of Agriculture, University of Arizona (Tucson, AZ), 1988-03)
      Residual effects from methyl bromide applied in 1986 showed increased yields in 1987. Increases from 115 to 281 pounds of lint per acre were observed, depending on the rate applied in 1986. This residual effect increases the possibility that this soil sterilant will be a useful tool to combat Texas root rot. Differences were also noted between 1986 and 1987 applications.
    • Resistance to Verticillium Wilt by Eight Varieties of Short Staple Cotton, Safford Agricultural Center, 1987

      Clark, Lee J.; Hine, Richard B.; Carpenter, Eddie W. (College of Agriculture, University of Arizona (Tucson, AZ), 1988-03)
      Eight short staple varieties were evaluated for severity of symptoms, percent of plants infected and yield while being grown in a Verticillium nursery on the Safford Agricultural Center. Delta Pine 90 showed the least severe symptoms, had the least number of infected plants and also yielded the highest. Another Delta Pine variety, DP 77, showed moderate symptoms and a 96% infection rate, but it still managed to come in third in yield, only 49 pounds per acre behind DP 90. Yield potential and varietal adaptability must be considered along with Verticillium wilt resistance in deciding what variety to plant, even in a field infested with Verticillium.
    • Development and Validation of a Simulation Model of Pink Bollworm Population Dynamics

      Huntchinson, Bill (College of Agriculture, University of Arizona (Tucson, AZ), 1988-03)
      A process- oriented simulation model of pink bollworm population dynamics in commercial cotton has been developed. The model, written in FORTRAN, is driven primarily by temperature and crop phenology. In addition to key ecological parameters, the model incorporates the impact of multiple insecticide applications. The model is presently being validated and modified for use as an on-line management tool.
    • Profitibility of the 1988 Upland Cotton Program

      Ayer, Harry W. (College of Agriculture, University of Arizona (Tucson, AZ), 1988-03)
      The profitability of full and "50/92" participation in the 1988 upland cotton program is estimated for representative farms in Maricopa, Pinal, LaPaz and Yuma counties. Special attention is given to the effect on profitability of farm size, multiple partner ownership and changes in program provisions for harvesting alfalfa hay. In general, full participation is shown to be the most profitable, given the assumptions used here.
    • Upland Cotton Defoliation Test

      Silvertooth, Jeff; Stedman, Sam (College of Agriculture, University of Arizona (Tucson, AZ), 1988-03)
      A field study was carried out to test the effectiveness of several defoliation treatments on Upland cotton in Pinal County. Three defoliation treatments were utilized. Results showed no significant differences among treatments in terms of percent leaf drop estimates taken seven and 14 days after initial application. Subsequent applications of defoliant materials were made to accomplish satisfactory levels of defoliation prior to harvest.
    • Effects of Two New Dropp™ Formulations on Cotton Defoliation

      Briggs, R. E.; Nelson, J. M. (College of Agriculture, University of Arizona (Tucson, AZ), 1988-03)
      Two new Dropp formulations show promise as cotton defoliants. In addition to excellent leaf drop, most squares, flowers, and young bolls were also shed, removing the food source for late season insects.
    • Effect of Spray Dilution and Rate of Pix Application on Long and Short Staple Cotton, Safford Agricultural Center, 1987

      Clark, Lee J.; Carpenter, Eddie W.; Silvertooth, Jeff (College of Agriculture, University of Arizona (Tucson, AZ), 1988-03)
      PIX was applied to long and short staple cotton in 5, 10 and 20 gallons of water in an incomplete factorial design involving 0.5, 1 and 2 pints of the product per acre. Plant heights were significantly shortened and the percent of lint obtained in the first picking was significantly increased when Piz was applied on the short staple cotton. No statistically significant yield differences were observed between the volumes of dilution or the rates of application for either long or short staple cotton. A factor underlying the experiment was that the monsoon rains. They kept the surface of the ground moist and the plants looking good; however, the subsurface moisture had apparently been depleted, and the plants were under some stress. This stressed condition offset what good the FIX might have done for yield.
    • Ripping After the Uprooter-Shredder-Mulcher

      Thacker, Gary; Rein, Brad; Silvertooth, Jeff (College of Agriculture, University of Arizona (Tucson, AZ), 1988-03)
      This test was conducted on the LDS Church Farm in Marana to determine whether ripping after the Uprooter-Shredder-Mulcher (USM) benefits yields. The three treatments were rip furrows only, rip -beds only, and no ripping after the USM. Depth of water penetration was measured after the preplant irrigation; no significant differences were observed between the treatments. Differences in lint yields were not statistically significant, although average lint yields for the ripped treatments were higher.
    • Douple Cropping with Controlled Traffic Tillage

      Thacker, Gary; Ottman, Mike (College of Agriculture, University of Arizona (Tucson, AZ), 1988-03)
      Double cropping barley and cotton, using a system of controlled traffic tillage, was compared to conventionally tilled, full-season cotton. In this test, the yields of the barley and late planted cotton were too low to be competitive with the full season cotton.
    • Factors Affecting the Response of Cotton to Preplant Application of EPTC (EPTAM) and butylate (Sutan +)

      Chernicky, J. P.; Heathman, S.; Hamilton, K. C.; Barstow, B. (College of Agriculture, University of Arizona (Tucson, AZ), 1988-03)
      Research was conducted at Maricopa, AZ with EPTC (S-ethyl dipropyl carbamothioate) (1.0 lb/a) and butylate (S-ethyl bis (2-methylpropyl)carbamothioate) (2.0 and 3.0 lb/a) in 1986 and 1987 to measure the response of cotton to preplant application methods. Butylate and EPTC were applied as either a preplant incorporated or preharrow treatments. The greatest injury to cotton and poorest weed control resulted when butylate or EPTC were applied on flat ground and incorporated to a depth of 2 inches or 4 to 6 inches. Adequate weed control and minimal injury to cotton was observed when these two thiocarbamates were applied preharrow.
    • Effects of Sewage Sludge on Heavy Metals in Cotton Seed

      Day, A. D.; Taylor, B. B.; Pepper, I. L.; Minnich, M. M. (College of Agriculture, University of Arizona (Tucson, AZ), 1988-03)
      In 1987, seed samples from three cotton fields in Avra Valley, Arizona, grown with liquid sewage sludge and inorganic nitrogen fertilizer, were analyzed for five heavy metals. Concentrations of cadmium, copper, lead, nickel, and zinc were similar in cotton seeds fertilized with either sewage sludge or inorganic nitrogen fertilizer. The levels of all five metals were well below the allowable EPA limits.
    • Greenhouse and Field Studies with Plant-Derived Oils for Control of the Sweet Potato Whitefly on Cotton

      Butler, G. D. Jr.; Henneberry, T. J.; Coudriet, D. L.; Broza, M. (College of Agriculture, University of Arizona (Tucson, AZ), 1988-03)
      Plant derived oils (cottonseed and soybean) in greenhouse and field studies were promising for sweet potato whitefly, Bemisia tabaci (Gennadius) control. Cotton seedlings treated with oil in the greenhouse repelled whiteflies up to 7 days and high mortality of treated larvae, pupae and adults occurred. In the field, application of crude cottonseed oil to cotton with high air-blast, ground spray equipment suppressed whitefly populations thoughout the season.
    • Effects of Sewage Sludge on Cotton Lint Quality

      Day, A. D.; Taylor, B. B.; Pepper, I. L.; Minnich, M. M. (College of Agriculture, University of Arizona (Tucson, AZ), 1988-03)
      Three field experiments were conducted in Avra Valley, Arizona, in 1986, to compare the lint quality of upland cotton fertilized with liquid sewage sludge with the lint quality of cotton fertilized with commercial inorganic fertilizer. Most lint quality components were similar for cotton fertilized with sewage sludge or inorganic nitrogen. Fertilization of cotton with sewage sludge tended to increase lint yield and decrease lint quality. Fertilization of cotton with sewage sludge increased vegetative growth and delayed lint maturity.
    • Pink Bollworm Egg-Larval Survivorship in Cotton Treated with Insecticides

      Hutchinson, Bill; Beasley, Bud; Henneberry, Tom (College of Agriculture, University of Arizona (Tucson, AZ), 1988-03)
      Pink bollworm egg -larval survivorship in insecticide -treated fields averaged (± SE) 19.8% (± 2.3) for the F2 and F3 generations developing during the primary boll producing time of the year (July and August). These observations have been useful in developing a simulation model of pink bollworm population dynamics.