• Pepper 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 varieties of bell peppers, three varieties of long green chile, two varieties of jalapeños, two varieties of yellow wax and one Serrano pepper were grown in a replicated small plot trial on the Safford Agricultural Center in 1998. Varieties were picked regularly during the growing season.
    • Postemergence Herbicide Weed Control in Cantaloupes

      Umeda, Kai; Byrne, David N.; Baciewicz, Patti (College of Agriculture, University of Arizona (Tucson, AZ), 1999-10)
      The addition of an adjuvant, Agridex, to halosulfuron or Basagran7 (bentazon) did not increase crop injury significantly compared to treatments without Agridex. The addition of Agridex to halosulfuron slightly improved morningglory (Ipomoea hederacea) control compared to without the use of an adjuvant. Bentazon at 1.0 lb/A plus Agridex gave very good morningglory control at 92%. At 2 WAT on 20 Aug, cantaloupe injury decreased for halosulfuron and bentazon treatments. A second application of halosulfuron at 0.05 lb/A did not cause additional crop injury.
    • Potential of Particle Film Technology for Insect Management in Crisp Head Lettuce

      Kerns, David L.; Tellez, Tony; Byrne, David N.; Baciewicz, Patti (College of Agriculture, University of Arizona (Tucson, AZ), 1999-10)
      A new insect management technology known as "particle film" technology (Surround) was evaluated for it potential for control early fall pests of head lettuce in Yuma, AZ. Surround did appear to slightly reduce larval population of cabbage looper, beet armyworm and Heliothis, but not enough to be considered a commercially effective treatment. Additionally, Surround appeared to antagonize Success’s activity towards cabbage loopers. Against whiteflies, Surround did appear to reduce ovipositioning, but resultant impact on the nymph population could not be adequately assessed. Overall, Surround does not appear to have good fit in the pest management system in leafy vegetables in Yuma, AZ.
    • A Practical Approach for Managing Lepidopterous Larvae with in Head Lettuce

      Palumbo, John C.; Byrne, David N.; Baciewicz, Patti (College of Agriculture, University of Arizona (Tucson, AZ), 1999-10)
      During the past 5 years, the efficacy and field performance of several new insecticides for control of Lepidopterous insects on desert lettuce crops has been investigated in small plot trials at the Yuma Agricultural Center and in produce fields with commercial cooperators. The objective has been to determine how these new chemistries will fit into pest management programs in Arizona. Thus, research programs have been focused on studies to define use patterns for these insecticides chemicals that can be integrated into our local management programs in the most cost-effective way possible. This report was created to provide an overview of the new chemistries being developed, their field activity and characteristics, and guidelines for use in head lettuce. In addition, an approach for sustaining the long-term efficacy of these products is discussed.
    • Preemergence Herbicide Combinations for Onion Weed Control

      Umeda, K.; MacNeil, D.; Byrne, David N.; Baciewicz, Patti (College of Agriculture, University of Arizona (Tucson, AZ), 1999-10)
      Most herbicides applied alone preemergence (PREE) caused minimal crop injury (<10%) when furrow irrigated. Pendimethalin (Prowl) applied at 0.5 lb AI/A plus bensulide (Prefar) at 6.0 lb AI/A under sprinkler irrigation in Tolleson caused crop injury that was highly unacceptable and the crop stand was severely reduced. Onion yields were significantly reduced for the Prowl plus Prefar treatments. Prowl at 0.25 or 0.5 lb AI/A alone provided very good (>90%) weed control of all weeds. Combination treatments of Prowl plus other herbicides provided very good weed control but did not offer enhanced control of weeds already controlled by Prowl alone. The combinations of ethofumesate (Nortron) with metolachlor (Dual) or dimethenamid (Frontier) gave improved weed control compared to when either was applied alone.
    • Preliminary Examination of the Population Dynamics and Control of the Lettuce Aphid on Romaine

      Palumbo, John C.; Byrne, David N.; Baciewicz, Patti (College of Agriculture, University of Arizona (Tucson, AZ), 1999-10)
      Several small plot studies were conducted during the spring of 1999 to examine the population growth, distribution and control of the lettuce aphid on romaine. The lettuce aphid population developed to greater numbers more quickly and spread among plants more rapidly when compared with other aphids species under late spring growing conditions. Most of the lettuce aphids sampled were found on the hearts of the plants rather than the frame and wrapper leaves. Our preliminary efficacy studies suggest that foliar sprays, when timed properly and with proper coverage, can provide adequate control of the lettuce aphid for up to 14 days. Furthermore, significant suppression of apterous lettuce aphid populations was observed in plots where pyrethoid treatment were sprayed for thrips control. The implications of these results for future research and management of lettuce aphids in desert lettuce is discussed.
    • Prowl and Prefar for Onion Weed Control

      Umeda, K.; MacNeil, D.; Lund, N.; Robertz, D.; Byrne, David N.; Baciewicz, Patti (College of Agriculture, University of Arizona (Tucson, AZ), 1999-10)
      Pendimethalin (Prowl7) applied preemergence (PREE) at 0.25 to 0.50 lb AI/A caused no observable injury and did not affect yields of onions that were furrow irrigated . Prowl applied PREE at 0.50 lb AI/A caused significant crop stand and yield reduction compared to lower rates or the untreated check under sprinkler irrigation. Prowl applied preplant incorporated (PPI) at rates ranging from 0.25 to 0.75 lb AI/A did not significantly injure onions or cause a significant yield reduction. Combination treatments of Prowl plus bensulide (Prefar7) applied PREE did not cause any measurable crop height or stand reduction compared to the standard treatment or untreated check. Prowl at 0.25 lb AI/A plus Prefar at 4.0 lb AI/A adequately controlled cheeseweed, yellow sweetclover, sowthistle, and London rocket.
    • Refinement of Release Techniques for Whitefly Parasitoids

      Byrne, David N.; Bellamy, David E.; Byrne, David N.; Baciewicz, Patti; Department of Entomology (College of Agriculture, University of Arizona (Tucson, AZ), 1999-10)
      Although they are currently effectively controlled by chemicals, sweet potato whiteflies have the potential to once again be a dominant pest in Arizona vegetables. We need to explore alternatives such as biological control so that we are not reliant solely on pesticides. We have been examining dispersal by the whitefly parasitoid Eretmocerus sp. in order to find more effective ways to deploy these agents in the field. We have learned in the laboratory that these wasps are efficient flyers since they are capable of moving into strong winds for more than 30 min. We also now know that most flight takes place within a short distance of the release point. We also have a better understanding of differences between male and female flight. This, along with other information we have obtained, will lead to our ability to effectively release these and parasitoids of other insect pests as well.
    • Residual Efficacy of New Insecticide Chemistries Against Cabbage Looper in Head Lettuce

      Palumbo, John C.; Byrne, David N.; Baciewicz, Patti (College of Agriculture, University of Arizona (Tucson, AZ), 1999-10)
      Several new insecticide chemistries were evaluated and compared with standard chemistries for residual efficacy against cabbage looper in lettuce. Four field trials were conducted at thinning, and heading stages of lettuce. These replicated trials clearly demonstrate that the new insecticides provide a solid 7 day residual efficacy (>90% control) following spray applications. Overall, Success at rates ranging from 4.5-6.0 oz/acre appeared to provide the most consistent residual activity on larvae present on plants at time of application. Confirm, appeared to have less consistent residual, but control was generally similar to Success. The newer compounds Proclaim and Avaunt, showed good residual efficacy for up to 7 days, and will be a welcome additions to the growers insecticide arsenal. Finally, the fact that all of these compounds are effective against large larvae, in part explains their consistent residual activity on lettuce.
    • 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.