• Alfalfa Variety Demonstration at the Safford Agricultural Center, 1984-1986

      Clark, Lee; Cluff, Ronald, E.; Ottman, Mike (College of Agriculture, University of Arizona (Tucson, AZ), 1987-09)
      Twenty non- dormant and very non -dormant alfalfa varieties were compared over three seasons. A very non -dormant variety Pioneer 5929 yielded the most during the 1986 season, with a yield approaching 12 tons per acre in six cuttings.
    • Winter Wheat Variety Trial in Cochise County, 1987

      Clark, Lee; Ottman, Mike (College of Agriculture, University of Arizona (Tucson, AZ), 1987-09)
      Sixteen winter wheat varieties (including three hybrids) were evaluated in a randomized, complete block experiment, with four replications. Stephens, the standard variety grown in the area, was outyielded by four of the winter wheat cultivars, including two of the hybrids. The highest yielding cultivar was a hybrid, Bounty 100, which yielded 5853 pounds per acre (23% higher than Stephens).
    • Durum Wheat Variety and Planting Rate Trial at Marana in 1987

      Thacker, Gary; Ottman, Mike; Ottman, Mike (College of Agriculture, University of Arizona (Tucson, AZ), 1987-09)
      Five varieties of durum wheat were evaluated at two different seeding rates, in cooperation with Pacheco Farm Management in Marana. Significant differences between varieties were observed in grain yield, plant height, lodging, bushel weight and protein level. No significant differences in yellow berry were observed between the varieties. The planting rates did not cause significant differences in grain yield nor in any of the other characteristics that were measured. There were no significant variety x planting rate interactions.
    • Yield Comparisons of Alfalfa Cultivars and Experimentals at Maricopa and Yuma, 1986 to July 1987

      Ottman, Mike; Smith, Steve; Tickes, Barry; Harper, John; Ottman, Mike (College of Agriculture, University of Arizona (Tucson, AZ), 1987-09)
      This study is part of an ongoing effort on evaluate alfalfa cultivar performance at various locations in Arizona. Forage yields of 25 alfalfa cultivars and experimentals were measured at the Maricopa and Yuma -Mesa Agricultural Centers. During the time period reported, many of the newer cultivars were more productive than the popular cultivar CUF 101 . Selection of alfalfa cultivars should be based upon fall dormancy, pest resistance, seed cost, and yield potential.
    • Double-Crop Grain Sorghum Variety Trial, Graham County, 1986

      Clark, Lee; Cluff, Ronald, E.; Ottman, Mike (College of Agriculture, University of Arizona (Tucson, AZ), 1987-09)
      Nine medium to medium -late maturing grain sorghum hybrids were compared for yield, percent moisture at harvest, bushel weight, plant height, percent bird damage and standability. The highest yielding entry in the trial was a new hybrid from Northrup King (NK 2656). Its yield of 6185 pounds per acre was 11% higher than the most, commonly grown hybrid in the area.
    • Performance of Germination Salt Tolerant Alfalfa on a Non-Saline Site

      Smith, Steve; Conta, Debra; Dobrenz, Albert; Ottman, Mike (College of Agriculture, University of Arizona (Tucson, AZ), 1987-09)
    • Seeding Rate, Nitrogen Rate, and Planting Date of One-Irrigation Barley at Marana, 1987

      Ottman, Mike; Ramage, Tom; Thacker, Gary; Ottman, Mike (College of Agriculture, University of Arizona (Tucson, AZ), 1987-09)
      One-irrigation barleys were bred to be grown with only a single irrigation near planting time. To further our understanding of how to manage these new cultivars, one-irrigation barleys were grown at 4 seeding rates (20, 40, 60, and 80 lbs seed /A), 4 nitrogen rates (0, 50, 100, and 150 lbs/A), and 3 planting dates (Nov. 17, Dec. 15, and Jan. 22). Seeding rates 01 40 to 60 lbs seed/A resulted in the highest yields at the Dec. 15 planting date, comparing all planting dates combined. However, in individual analyses of the Nov. 17 and Jan. 22 planting dates, no significant differences in yield due to seeding rate were detected. Grain yield increased linearly with nitrogen rate at the Nov. 17 planting date, but was not influenced by nitrogen rate at the other planting dates. Yields were similar for the Nov. 17 and Dec. 15 planting dates, but decreased considerably in the Jan. 22 planting date due partially to lower head number. Grain yields of 2-22-9 were consistently higher than Seco this year.
    • Genetic Gains and Stability for Germination Salt Tolerance in Alfalfa

      Poteet, David; Robinson, David; Smith, Steve; Dobrenz, Albert; Ottman, Mike (College of Agriculture, University of Arizona (Tucson, AZ), 1987-09)
      Improving the germination salt tolerance of alfalfa will help this crop endure both increasingly saline irrigation water and salt build -up in the soil. Seven previous cycles of selection for salt tolerance at germination plus the parental line, Mesa-Sirsa, were evaluated for percentage germination under various levels of NaCI solutions. Germination improved linearly from the earliest to the latest cycle of selection. Germination salt tolerance can be improved through recurrent selection techniques.
    • Small Grain Variety Comparisons at the Yuma Agricultural Center in 1987

      Thompson, Rex; Sheedy, Michael; Ottman, Mike (College of Agriculture, University of Arizona (Tucson, AZ), 1987-09)
    • Wheat Germplasm Releases by the Agricultural Experiment Station in 1987

      Thompson, Rex; Ottman, Mike (College of Agriculture, University of Arizona (Tucson, AZ), 1987-09)
    • Strain Crossing for Large-Leaflet Alfalfa: A First Look

      Dobrenz, Albert; Robinson, David; Smith, Steve; Ottman, Mike (College of Agriculture, University of Arizona (Tucson, AZ), 1987-09)
    • Russian Wheat Aphid, Diuraphis noxia (Mordvillko): A New Insect Pest of Small Grains in Arizona

      Dick, Gary; Moore, Leon; Ottman, Mike (College of Agriculture, University of Arizona (Tucson, AZ), 1987-09)
    • Dryland Catchment Test Planted to Hybrid Sorghum and Pearl Millet in Avra Valley Near Three Points, 1986

      Thacker, Gary; Voigt, Robert; Schmalzel, Carl; Ottman, Mike; Ottman, Mike (College of Agriculture, University of Arizona (Tucson, AZ), 1987-09)
    • Wheat Variety Demonstration in Roll, 1987

      Tickes, Barry; Ottman, Mike; Ottman, Mike (College of Agriculture, University of Arizona (Tucson, AZ), 1987-09)
    • Oat Hay Variety Evaluation

      Harper, John; Ottman, Mike (College of Agriculture, University of Arizona (Tucson, AZ), 1987-09)
    • Response of Alfalfa to Phosphorus Fertilizer Sources

      Stroehlein, Jack; Clark, Lee; DeRosa, Edith; Ottman, Mike (College of Agriculture, University of Arizona (Tucson, AZ), 1987-09)
      A field study was carried out to determine the effects of different fertilizers on yield and quality of alfalfa. Two harvests over a period of four cuttings did not reveal any differences due to treatment. While alfalfa often responds to phosphorus (P) fertilizer application, conditions in this study provided adequate P as well as nitrogen (N) and potassium (K).
    • Predicting the Nitrogen Requirements of Irrigated Durum Wheat in Graham County Using Soil and Nitrate Analysis

      Doerge, Thomas; Knowles, Tim; Ottman, Mike; Clark, Lee; Ottman, Mike (College of Agriculture, University of Arizona (Tucson, AZ), 1987-09)
      The high yielding spring wheats grown in Arizona usually require applications of fertilizer nitrogen (N) to achieve optimum grain yields and acceptable quality. The University of Arizona's currently recommended procedure (preplant soil plus periodic stem tissue analysis for NO₃-N to predict the N needs of wheat) is not widely used by Graham County growers for various reasons. A nitrogen fertility trial was conducted at the Safford Agricultural Center during the 1986-87 crop year to: 1) examine the relationships between basal stem nitrate-N levels, grain yields of durum wheat, and N fertilizer rates; and 2) to test the accuracy of the recommended procedure for predicting the N needs of durum wheat. Five rates of N from O to 419 lbs N /acre were applied in three split applications. One additional N treatment was made as indicated by the current University of Arizona procedure. Maximum grain yields of 5500 to 6200 lbs /a and protein levels in excess of 14.5% were attained with the application of at least 186 lbs NIA. An untimely early season irrigation induced a temporary N deficiency condition for all plots, which may have kept grain yields below the maximum yield possibility for this site. In spite of this, the amount of N predicted by the University of Arizona procedure (197 lbsN/acre) did attain an adjusted economic return which was not significantly different from the maximum numerical yield that was achieved for any of the other N treatments.
    • Effects of Sewage Sludge on the Yield and Quality of Wheat Grain and Straw

      Day, Arden; Swingle, Spencer; Taylor, Brooks; Pepper, Ian; Minnich, Martha; Ottman, Mike (College of Agriculture, University of Arizona (Tucson, AZ), 1987-09)
      Experiments were conducted in Avra Valley, Arizona, to study the use of digested liquid sewage sludge as a source of plant nutrients in the commercial production of grain and straw from wheat. Wheat grown with the recommended amount of plant -available nitrogen from sewage sludge produced the same grain yield as wheat grown with the same amount of nitrogen from inorganic fertilizer. Wheat grain and straw grown with sewage sludge and inorganic fertilizer had similar livestock feeding qualities. Fertilizing wheat with sewage sludge delayed maturity.
    • Stomatal Response to Water Stress in Two Pearl Millet Genotypes

      Osman, Mohamoud; Dobrenz, Albert; Tewolde, Haile; Voigt, Robert; Ottman, Mike (College of Agriculture, University of Arizona (Tucson, AZ), 1987-09)
      A study was conducted in the field to test whether stomatal sensitivity to water stress can be used as a selection criterion for drought tolerance in two pearl millet genotypes. In both cultivars, stomatal aperture was significantly reduced by the water stress. However, the proportion of reduction per 20 mm decrease in applied water was much higher for the hybrid than for the female parent. This is clearly an indication of a higher stomatal sensitivity in the hybrid, which probably explains the superior performance under water stress that was previously observed in this genotype.
    • Gypsum Application on Wheat at Coolidge, 1987

      Ottman, Mike; Stroehlein, Jack; Christian, Tom; Ottman, Mike (College of Agriculture, University of Arizona (Tucson, AZ), 1987-09)
      Gypsum is applied to alleviate the problems associated with sodium- affected soils, such as surface crusting and impeded water infiltration. Due to the uncertainties in identifying gypsum-responsive sites, field studies were initiated to further our understanding of conditions responsible for the response of wheat to gypsum applications. Gypsum was applied at rates ranging from 0 to 4 T/A on two commercial farms near Coolidge, AZ. No differences in wheat grain yield, grain protein, stand, grain bushel weight, or plant height were detected at the 5% probability level at either site with the exception of increased plant height at one site. The positive benefits of gypsum have been documented in the past with certain soils; this study is just one of many required to more positively define gypsum-responsive sites in Arizona. The economics of gypsum application involves delivery and application cost of gypsum and the change in yield and value of subsequent crops.