• Alfalfa Herbicide Trial Greenlee County, 1989

      Clark, L. J.; Heathman, E. S.; DeRosa, E.; Cluff, R. E.; Ottman, Michael; Kingdon, Lorraine (College of Agriculture, University of Arizona (Tucson, AZ), 1989-09)
      Replicated herbicide experiments were carried out on alfalfa fields in Graham and Greenlee counties in the winter of 1989. Five herbicides were tested; tanzy mustard and (oxtail barley were the mails target weed species. Velpar L applied on at a rate of 4 pints per acre in 20 gallons of water provided the best control with 99% control of the broad -leafed weeds and 86% of the grassy weeds just prior to the first cutting. Better control of foxtail barley probably would have been achieved by several of the herbicides if they had been applied earlier, before the weeds germinated and /or if the materials had been incorporated by an adequate irrigation or rainfall.
    • Alfalfa Variety Demonstration at the Safford Agricultural Center, 1988

      Clark, L. J.; Cluff, R. E.; Carpenter, E. W.; Ottman, Michael; Kingdon, Lorraine (College of Agriculture, University of Arizona (Tucson, AZ), 1989-09)
      A new alfalfa variety trial was planted in the fall of 1987to replace the previous four-year trial. The top varieties from the previous trial were placed in the new trial, along with new, promising varieties. A single year's data is insufficient to judge the performance of a variety during its useful years of production. The data simply indicate performance in their first year. Pioneer 5929, the variety that had the best overall yield in the previous trial (1), performed well in this trial as well. However, Mecca, a new variety from Plant Genetics, Inc., had the highest yield.
    • Alfalfa Variety Trial in Greenlee County, 1988

      Clark, L. J.; DeRosa, E.; Ottman, Michael; Kingdon, Lorraine (College of Agriculture, University of Arizona (Tucson, AZ), 1989-09)
      For the past three years, ten alfalfa varieties have been grown and yields recorded. Yields in excess of 9 tons per acre were harvested in 1988 on 7 of the 10 varieties. Baron, a moderately nondormant variety, was the highest yielding variety for the three years, with an average yield of 8.9 tons per acre.
    • Effect of Fungicides on Development of Cercospora Summer Black Stem and Leaf Spot in Alfalfa

      Matheron, M.; Winans, S.; Rethwisch, M.; Ottman, Michael; Kingdon, Lorraine (College of Agriculture, University of Arizona (Tucson, AZ), 1989-09)
      Cercospora summer black stem and leaf spot, a fungal disease of alfalfa, has been associated with a stand decline problem in La Paz County. In a continuation of a study initiated in 1987, we examined the ability of three fungicides to control the disease and decline problem. Bravo, Funginex, and Kocide significantly reduced the severity of Cercospora summer black stem and leaf spot. In addition, significant increases in yield were recorded on plots treated with fungicides.
    • Improved Regrowth Salt Tolerance in Alfalfa

      Johnson, D. W.; Smith, S. E.; Dobrenz, A. K.; Ottman, Michael; Kingdon, Lorraine (College of Agriculture, University of Arizona (Tucson, AZ), 1989-09)
    • Progress in the Development of Salt Tolerance in Alfalfa

      McKimmie, T.; Dobrenz, A. K.; Malchow, P. L.; Ottman, Michael; Kingdon, Lorraine (College of Agriculture, University of Arizona (Tucson, AZ), 1989-09)
      Increasing crop salt tolerance can mean higher yields on irrigated farmland and salt -affected soils. Three cycles of selection were made for growth of alfalfa seedlings under 7500 ppm NaCl. Comparison of parent and selected populations was made for yield and germination under saline conditions. Yield of the last cycle was significantly improved. Germination of the last two cycles was higher than that of the parent and cycle 1.
    • Variability in Salt Tolerance within a Population of Alflafa

      McKimmie, T.; Dobrenz, A. K.; Ottman, Michael; Kingdon, Lorraine (College of Agriculture, University of Arizona (Tucson, AZ), 1989-09)
      Genetic variability must exist for a selection program to be successful. Alfalfa seedlings were selected for salt tolerance after six weeks growth at 7500 ppm NaCl. The selection criteria considered plant height and survival. Variability for each factor within a population of alfalfa was shown. Both criteria were important and facilitated selection from those parents which contributed most to the salt tolerance of the population.