• The Comparison of Aerial and Sprinkler Applied Delayed Applications of Kerb® to Lettuce

      Tickes, Barry; Byrne, David N.; Baciewicz, Patti (College of Agriculture and Life Sciences, University of Arizona (Tucson, AZ), 2004-09)
      Five tests were conducted to compare delayed applications of Kerb applied by air with applications made through sprinklers. Applications were made commercially to plots ranging in size from 11 to 18 acres. Broadleaf weed control was better in all tests from the sprinkler applied Kerb than from aerial application. The control of volunteer sudangrass was poor in one test from both types of applications and worse from the sprinkler than the aerial application. It was concluded that applying Kerb though sprinklers to lettuce is effective and often superior to aerial applications.
    • The Effect of UV-Reflective Mulching on Yield and Quality of Cantaloupes

      Fonseca, Jorge; Byrne, David N.; Baciewicz, Patti (College of Agriculture and Life Sciences, University of Arizona (Tucson, AZ), 2004-09)
      Three trials, one during Fall 2003 season and two during the spring 2004, were conducted at the Yuma Agricultural Center to investigate the influence of UV reflective mulching on yield and quality of cantaloupes. We report here results from the first two trials. The results showed that reflective mulching increased the total number of fruits by over 25%. The silver film allowed early harvesting, it produced fruits with higher content of soluble solids (°Brix), pulp with more intense color, and early-harvested fruits with higher content of vitamin C. This technique seems promising for the production of melons and probably other cucurbits but the grower is ultimately the one who needs to determine whether the economical return, associated with the mulch, compensates the costs of implementing it in their fields.
    • Yield and Microbial Quality of Head Lettuce as Affected by Field Moisture at Harvest

      Fonseca, Jorge; Byrne, David N.; Baciewicz, Patti (College of Agriculture and Life Sciences, University of Arizona (Tucson, AZ), 2004-09)
      The effect of moisture conditions on microbial quality (as total aerobic bacteria) and yield of head lettuce was investigated. Head lettuce cv. Honcho II grown at the Yuma Agricultural Center was evaluated for microbial population at harvest and postharvest quality either following different irrigation termination schedules or after a rainfall event. The last irrigation was scheduled 24, 16 and 6 days prior to harvest resulting in soil’s water content of 15.9%, 17.0% and 17.2%, respectively, at harvest. Lettuce receiving the last irrigation 6 days before harvest had 10% more weight, higher total aerobic bacteria and shorter shelf life than plants irrigated 24 days before harvest. The plants with the last irrigation scheduled 16 days before harvest showed similar weight at harvest, lower total aerobic count and longer shelf life than plants with irrigation termination scheduled 6 days prior to harvest. The effect of field’s moisture prior to harvest on quality was further evaluated with lettuce harvested 1 and 7 days after a rainfall event. A day after rain the microbial population in both outer leaves and head leaves increased. The microbial population in head leaves continued increasing during the week after rain. The results from this study suggest that managing moisture conditions at harvest is important to enhance quality of lettuce. Although the potential decrease in weight produced with an early irrigation termination is a great concern of growers, it was shown in this study that excessively late pre-harvest irrigation of lettuce is not necessary to obtain maximum weight at harvest.