• The Influence of Sewage Sludge on Nitrogen Availability, Crop Growth, and Yield at Marana, 1988

      Ottman, M. J.; Day, A. D.; Pepper, I. L.; Taylor, B. B.; Silvertooth, Jeff; Isbell, Joan (College of Agriculture, University of Arizona (Tucson, AZ), 1989-03)
    • Management of Rootknot Nematode in Arizona Cotton

      Nigh, E. L. Jr.; Silvertooth, Jeff; Isbell, Joan (College of Agriculture, University of Arizona (Tucson, AZ), 1989-03)
    • On Farm Cotton Irrigation Scheduling Management Using Infrared Thermometers in Arizona

      Garrot, D. J. Jr.; Fangmeier, D. D.; Husman, S. H.; Stedman, S.; Silvertooth, Jeff; Isbell, Joan (College of Agriculture, University of Arizona (Tucson, AZ), 1989-03)
    • Tierra Prospera Farms CWSI Irrigation Scheduling Demonstration Test

      Garrot, D. J. Jr.; Stedman, S.; Benedict, D. B.; Silvertooth, Jeff; Isbell, Joan (College of Agriculture, University of Arizona (Tucson, AZ), 1989-03)
    • Short Staple Variety Demonstrations, Pinal County

      Malcuit, J.; Stedman, S.; Silvertooth, J.; Silvertooth, Jeff; Isbell, Joan (College of Agriculture, University of Arizona (Tucson, AZ), 1989-03)
    • Response of Texas Root Rot to an Application of a Soil Sterilant in Marana, 1988

      Thacker, Gary; Silvertooth, Jeff; Silvertooth, Jeff; Isbell, Joan (College of Agriculture, University of Arizona (Tucson, AZ), 1989-03)
      Methyl bromide/chloropicrin (MB/C), a soil sterilant, was deep injected into cotton beds 6 days before planting in 1988. Application rates were zero, 300, 400, and 500 pounds of MB/C per acre, injected 18-inches deep into the sandy loam soil. Short staple lint yields in all of the MB/C treatments were significantly higher than the untreated check. MB/C at all application rates was 100% effective in preventing the plants from dying from the disease, while 86% of the plants in the untreated check plots died.
    • Profenofos as an Ovicide for Heliothis spp. In Short Staple Cotton and Comparison of the Ovicidal and Commercial Efficacy of Profenofos and Two Tank Mixes

      Dick, G. L.; Moore, L.; Silvertooth, Jeff; Isbell, Joan (College of Agriculture, University of Arizona (Tucson, AZ), 1989-03)
    • Regional Variety Test

      Pegelow, E. J. Jr.; McAlister, A. C.; Silvertooth, Jeff; Isbell, Joan (College of Agriculture, University of Arizona (Tucson, AZ), 1989-03)
    • Pima Cotton Genetics

      Percy, R. G.; Turcotte, E. L.; Silvertooth, Jeff; Isbell, Joan (College of Agriculture, University of Arizona (Tucson, AZ), 1989-03)
      Seed increase of 104 accessions and data collection on 65 accessions were obtained in 1988 to further the maintenance and evaluation of the Gossypium barbadense L. germplasm collection. In a program of conversion of tropical non flowering cottons to a day-neutral flowering habit, 63 accessions were advanced 1 generation by backcross. A systematic screening of the G. barbadense collection for bacterial blight resistance involving 200 accessions from 21 countries yielded 8 accessions resistant to races 1, 2, 7, and 18 of the pathogen. Genetic inheritance and linkage investigations of a male sterile and a foliar mutant progressed. An investigation of the geographic and taxonomic distribution of the ovate leaf trait was concluded with negative results. The frequency of the 2 mutant genes ov₁ and ov₂ proved to be too rare to yield meaningful taxonomic or geographic information about the species. Preliminary results from a performance evaluation of interspecific hybrid cottons conducted at Maricopa and Safford AZ, indicated strong environmental influences on hybrids, but generally favorable yield earliness and plant height data were obtained from the higher -elevation Safford location.
    • Cotton Irrigation Scheduling, Safford Agricultural Center, 1988

      Clark, L. J.; Carpenter, E. W.; Scherer, T.; Slack, D.; Fox, F.; Silvertooth, Jeff; Isbell, Joan (College of Agriculture, University of Arizona (Tucson, AZ), 1989-03)
      Cotton was grown using historical evapotranspiration data in the Erie method a checkbook method using real-time AZMET weather data, an infrared thermometer, and a faint manager to schedule irrigations. Yields of 4 bales per acre were recorded with no significant differences between the scheduling methods. Differences were seen in the plant growth and maturity. More refining will be done in subsequent investigations.
    • Scheduling Pima Cotton Irrigations Using Infrared Thermometers

      Garrot, D. J. Jr.; Fangmeier, D. D.; Husman, S. H.; Silvertooth, Jeff; Isbell, Joan (College of Agriculture, University of Arizona (Tucson, AZ), 1989-03)
      Plots of pima S-6 cotton were scheduled for irrigation using the Crop Water Stress Index (CWSI). Irrigations were applied when CWSI levels reached 0.08 (wet), 0.34 (medium), and 0.68 (dry) units. The medium treatment had significantly higher lint yield. Preliminary test results indicate the CWSI can be useful in irrigation-management decisions regarding pima cotton production.
    • Aflatoxin Contamination of Cottonseed From Pink Bollworm Damaged Bolls

      Cotty, P. J.; Lee, L. S.; Silvertooth, Jeff; Isbell, Joan (College of Agriculture, University of Arizona (Tucson, AZ), 1989-03)
      Aflatoxin contamination of cottonseed from bolls damaged by the pink bollworm was compared with contamination of cottonseed from undamaged bolls. Cottonseed produced in pink bollworm damaged bolls was the predominant source of aflatoxin contaminated cottonseed.
    • The 1989 Upland Cotton Program: How Profitable for Arizona Producers?

      Ayer, H. W.; Silvertooth, Jeff; Isbell, Joan (College of Agriculture, University of Arizona (Tucson, AZ), 1989-03)
      The profitability of full and "50/92" participation in the 1989 upland cotton program was estimated for representative farms in Maricopa, Pinal, LaPaz and Yuma counties. Special attention was given to the effect on profits of the reduction in permitted acreage, and to farm size and multiple-partner ownership. Full participation was more profitable than "50/92" or nonparticipation given the assumptions used here. The expected profitability of the crops used on 'free acres" in the large farm case -- alfalfa or pima cotton --has a major positive effect on program profitability. The possible use of upland base acres to produce pima cotton or durum wheat, given the current high prices of those crops, is also discussed.
    • Strategies to Capture Higher Gross Revenues

      Firch, R. S.; Silvertooth, Jeff; Isbell, Joan (College of Agriculture, University of Arizona (Tucson, AZ), 1989-03)
      Research on futures price behavior indicates that farmers may find it feasible to use selective hedging or forward contracting to increase gross receipts from the sale of their commodities. University economists have been telling farmers for many years that selective hedging-hedging only in some years rather than all years or no years -- should not be considered as an alternative to hedging every year or never hedging. If selective hedging is to be a feasible strategy for farmers, they must have some system for correctly predicting the direction of futures price changes during the production period in most years.
    • Cotton Response to Water and Nitrogen, 1988

      Roth, R. L.; Gardner, B. R.; Silvertooth, Jeff; Isbell, Joan (College of Agriculture, University of Arizona (Tucson, AZ), 1989-03)
      Water - nitrogen production functions were determined for cotton cultivars, DPL 77 and DPL 90. Cotton yields for the DPL 90 cultivar were reduced more than the DPL 77 cultivar when water applications were reduced. Cotton yields of 3.0 to 3.4 bales/acre were predicted for nitrogen applications of 160 to 210 lbs/acre with appropriate water applications.
    • Energy Consumption and Yields for Cotton Tillage Systems

      Rein, B. K.; Thacker, G. W.; Coates, W. E.; Silvertooth, Jeff; Isbell, Joan (College of Agriculture, University of Arizona (Tucson, AZ), 1989-03)
      The energy consumption of 2 alternative tillage systems for continuous cotton production in Arizona were compared to a conventional system. The tests were conducted at the University of Arizona Marana Agricultural Center. Results of the study in a Pima I clay loam soil showed the sundance treatment to have the lowest energy requirement of 39 Hp-hr /ac (73 kW-h/ha); the USM system had the second highest of 58 Hp-hr /ac (107 kW-h/ha). The conventional system required 67 Hp-hr /ac (124 kW- h/ha). Average yields for all 3 systems were not significantly different. A continuation of this study will be conducted to determine long-term effects on energy consumption, yields, and soil compaction.
    • Response of Cotton to a Preplant Zinc Sulfate Application

      Hofmann, W. C.; Else, P. T.; Silvertooth, Jeff; Isbell, Joan (College of Agriculture, University of Arizona (Tucson, AZ), 1989-03)
      The effect of a single preplant application of zinc sulfate on DPL 77 yield was investigated at the Maricopa Agricultural Center on a field that had tested as marginal with respect to zinc availability. No significant difference in yield was found between the plants receiving zinc sulfate and the control.
    • Response of Cotton to Various Fertilization Histories

      Hofmann, W. C.; Else, P. T.; Silvertooth, Jeff; Isbell, Joan (College of Agriculture, University of Arizona (Tucson, AZ), 1989-03)
      Effects of various fertilization histories on cotton yield were investigated for the fourth consecutive year in the same field at the Maricopa Agricultural Center. Treatments included: 1) no fertilizers added for the past 4 seasons, 2) aggressive nitrogen fertilization in the 1988 season, no fertilization for the previous 3 seasons, 3) standard nitrogen fertilization in 1988 similar treatment for the previous 3 seasons, 4) aggressive nitrogen fertilization in 1988 same history as treatment #3 for previous 3 seasons, and 5) a commercial alternative fertilization program (BioHumaNetics, Inc.). Yields in 1988 were significantly different with treatment 2 having the highest yield followed by treatments 3 and 4, followed by treatment 5; treatment 1 had the lowest yield.
    • Short Staple Variety Trial, Cochise County, 1988

      Clark, L. J.; Schwennesen, E.; Silvertooth, Jeff; Isbell, Joan (College of Agriculture, University of Arizona (Tucson, AZ), 1989-03)
      Nine acala varieties were grown in the Cochise area of Cochise county. An experimental New Mexico variety B510 was the top yielder in the test, producing 1,287 pounds of lint per acre. The top variety in 1987, 1517-77BR, was next to the bottom in the 1988 test, probably due to low plant population. Variety characteristics such as plant height, wilt susceptibility, relative maturity and lint turnout are quantified in the study along with final plant populations and lint quality. Information on cotton variety strip trials implemented in the county is also given.
    • Evaluation of PIX Multiple Application Treatments on Upland and Pima Cotton in Arizona, 1988

      Silvertooth, J. C.; Howell, D. R.; Farr, C. R.; Malcuit, J. E.; Silvertooth, Jeff; Isbell, Joan (College of Agriculture, University of Arizona (Tucson, AZ), 1989-03)
      Four field experiments were conducted in Arizona in 1988 to evaluate the effects of various multiple application treatment combinations of PIX on the growth and development, as well as the lint yields of both upland and pima cotton. Plant height was significantly reduced (P ≤ 0.05) in some FIX treatments in comparison to the checks for short periods of time after the treatment applications. Those effects did not persist, nor did they translate into any significant positive differences among treatments in terms of lint yields for either of the upland or pima experiments.