• S-1812 Lepidopterous Insect Pest Control in Broccoli Study

      Umeda, K.; Strickland, B.; Byrne, David N.; Baciewicz, Patti (College of Agriculture, University of Arizona (Tucson, AZ), 1999-10)
      A single application of S-1812 (Valent) at 0.15 and 0.20 lb AI/A effectively reduced Plutella xylostella (diamondback moth, DBM) in broccoli compared to the untreated check. S-1812 at 0.15 lb AI/A performed similar to thiodicarb (Larvin) at 1.0 lb AI/A. S-1812 significantly reduced the DBM at 5 days after treatment (DAT) and control was effective for up to 14 DAT. S-1812 was less effective against Trichoplusia ni (cabbage looper, CL) compared to DBM control efficacy or Larvin. S-1812 reduced the development of small CL to larger sized larvae.
    • Soil-Applied Insecticides for Whitefly Control in Fall Cantaloupes

      Umeda, K.; Byrne, David N.; Baciewicz, Patti (College of Agriculture, University of Arizona (Tucson, AZ), 1999-10)
      CGA-293343 and Admire applied to the soil at planting time provided good control of WF at rating dates 34, 45, and 52 DAP. Cantaloupes treated with CGA-293343 at 0.09 lb AI/A showed a greater increase in number of immatures after 45 DAP compared to the CGA-293343 at 0.18 lb AI/A applied on melons. At 59 DAP, the higher rate of CGA-293343 continued to reduce the number of immatures compared to the lower rate and untreated check. Admire treated melons with or without a subsequent foliar insecticide treatments showed reduced WF nymphs at 45 and 52 DAP or 10 and 17 days after treatment (DAT) of foliar applications. Foliar applications of Applaud or Asana plus endosulfan did not significantly reduce WF immatures compared to a single at-planting time application of Admire. The application of either foliar treatment did not extend the length of control beyond that offered by the Admire treatment.
    • Studies of Resistance of Beet Armyworm (Spodoptera exigua) to Spinosad in Field Populations from the Southern USA and Southeast Asia

      Moulton, J. K.; Pepper, D. A.; Dennehy, T. J.; Byrne, David N.; Baciewicz, Patti; Extension Arthropod Resistance Management Laboratory, Department of Entomology (College of Agriculture, University of Arizona (Tucson, AZ), 1999-10)
      Susceptibility to spinosad (Success®/Tracer®) of beet armyworm (Spodoptera exigua) from the southern U.S.A. and Southeast Asia was determined through exposure of third instar larvae to dipped cotton leaves. LC₅₀ values of field populations ranged from 0.6 to 14 μg spinosad/ml. Field populations were 3.0 to 70-fold less susceptible to spinosad than was a susceptible reference population. The least susceptible population was collected from Thailand. We hypothesized that this population was resistant to spinosad because: (1) it was significantly less susceptible to spinosad than all other populations evaluated and than any other reports in the literature; (2) it regained susceptibility while in culture; (3) it was collected from a region of very intensive insecticide use and severe insect resistance problems; and (4) it exhibited significant survivorship on field-treated cabbage leaves. Piperonyl butoxide (PBO), diethyl maleate (DEM), and S,S,S tributyl-phosphorothiolate (DEF) failed to synergize spinosad in this resistant Thailand population, and PBO failed to do so in the least susceptible domestic population evaluated, the Parker, AZ, field strain. However, the synergist and field residue studies were conducted using a Thailand population that had levels of resistance that declined while in laboratory culture.
    • Sweet Corn Herbicide Weed Control Study

      Umeda, K.; Byrne, David N.; Baciewicz, Patti (College of Agriculture, University of Arizona (Tucson, AZ), 1999-10)
      The soil applied herbicides EPTC plus safener (Eradicane7), metolachlor (Dual)7, dimethenamid (Frontier7), pendimethalin (Prowl7), and fluthiamide/metribuzin (Axiom7) applied at planting time all provided very good weed control of pigweeds (Amaranthus spp.), grasses, and puncturevine (Tribulus terrestris). Most of the soil applied followed by POST combination treatments gave very good control (>90%) of lambsquarters (Chenopodium spp.), pigweeds, and groundcherry (Physalis wrightii). POST treatments bentazon (Basagran7), dicamba (Clarity7), and diflufenzopyr plus dicamba (Distinct7) applied alone were not as effective as combinations with soil applied herbicides.
    • Sweet Corn Variety Trial Safford Agricultural Center, 1998

      Clark, L. J.; Walser, R.; Carpenter, E. W.; Byrne, David N.; Baciewicz, Patti (College of Agriculture, University of Arizona (Tucson, AZ), 1999-10)
      Eight sweet corn varieties were grown in a replicated small plot trial on the Safford Agricultural Center in 1998. Snow White had the highest yield per acre with several of the other varieties producing very acceptable yields. Yields seen in the small plots may not be obtainable in commercial fields, but yield relations between varieties should be the same for both situations.
    • Timing of Postemergence Herbicides for Onion Weed Control

      Umeda, K.; Gal, G.; Strickland, B.; Byrne, David N.; Baciewicz, Patti (College of Agriculture, University of Arizona (Tucson, AZ), 1999-10)
      Bromoxynil (Buctril®) at 0.063, 0.094, and 0.125 lb AI/A was completely safe on onions treated at the early first true leaf stage of growth. Onions did not exhibit visual injury at 12 days after treatment (DAT) and height was not different from the untreated at 45 DAT. Melilotus officinalis (yellow sweetclover) was only marginally controlled by both Buctril and oxyfluorfen (Goal®). Goal provided better weed control with an earlier application timing at 0.063 lb AI/A than the later application at 0.25 lb AI/A. All herbicide treated onions yielded higher than the untreated. A rate response was observed for Buctril and Goal where onion yields were higher for the higher rates of application. Results indicate that the POST herbicides at lower than typical use rates were safe when applied to onions at an early timing. Effective weed control of some weeds was observed but yellow sweetclover was not adequately controlled.
    • Tomato Variety Trial Safford Agricultural Center, 1998

      Clark, L. J.; Walser, R.; Carpenter, E. W.; Byrne, David N.; Baciewicz, Patti (College of Agriculture, University of Arizona (Tucson, AZ), 1999-10)
      Four slicing and two Roma-type tomato varieties were grown in a replicated small plot trial on the Safford Agricultural Center in 1998. Varieties were picked regularly during the growing season with total tonnage picked being tabulated and plot weights by variety shown graphically against time during the season. Balboa variety of slicing tomato and Toro variety of Roma-type tomato were the highest yielding varieties with yields of 69 and 76 tons per acre respectively.