• Effect of Preplant Fumigation on Yield of Chile Pepper Infected with Root-Knot Nematode

      Olsen, M.; McClure, M.; Husman, S.; Byrne, David N.; Baciewicz, Patti (College of Agriculture, University of Arizona (Tucson, AZ), 2000-08)
      A field test was established in 1999 to determine the effect of preplant soil fumigation on yield of chile pepper in southeastern Arizona in order to give growers data on which to base management decisions. Replicated plots within a nematode-infested field planted with New Mex 6-4 chile in March 1999 were either treated with Telone II fumigant at 7 gal/A two weeks before planting or not treated. In a mid-season assay in July 1999, the effects of fumigation were evident in plant canopy growth although numbers of J2/cc soil were not significant between treatments (p=0.058). Differences in yields between fumigated plots and untreated plots were significant (p=0.014). The average yield in fumigated plots was 12.4% higher than that in untreated plots.
    • New Insecticides for Diamondback Moth Control in Cabbage

      Umeda, K.; MacNeil, D.; Roberts, D.; Byrne, David N.; Baciewicz, Patti (College of Agriculture, University of Arizona (Tucson, AZ), 2000-08)
      At 3 days after the first application, RH-2485, Success, Proclaim, Avaunt, and Larvin reduced the total number of diamondback moth (DBM) larvae to less than 2.0 larvae per 10 plants compared to the untreated that had 7.0 larvae/10 plants. Alert, Kryocide, and S-1812 treated cabbage exhibited 4.0 to 5.0 larvae/10 plants and Lannate was intermediate with 2.7 total larvae/10 plants. Following a second application, Success and Proclaim completely controlled DBM for one week. Success, Proclaim, Alert, and Larvin continued to offer very good control of DBM for two weeks after the second application. S-1812 performed similarly to Lannate.
    • Comparative Effect of Five Fungicides on the Development of Root and Stem Rot and Survival of Chile Pepper Plants Grown in Field Soil Naturally Infested with Phytophthora capsici

      Matheron, Michael E.; Porchas, Martin; Byrne, David N.; Baciewicz, Patti (College of Agriculture, University of Arizona (Tucson, AZ), 2000-08)
      Five different fungicides, including azoxystrobin, dimethomorph, fluazinam, fosetyl-Al, and mefenozem (metalaxyl), were evaluated for their ability to inhibit the development of root and crown rot and increase the survival of chile pepper plants grown in soil naturally infested with Phytophthora capsici. For chile pepper plants grown in field soil naturally infested with P. capsici and subjected to a 48 h flood period every 2 weeks, growth and survival of plants receiving one treatment of dimethomorph at 100 μg/ml or fluazinam at 1,000 μg/ml were significantly greater than that for plants treated once with azoxystrobin at 1,000 μg/ml or fosetyl-Al at 3,000 μg/ml. For each tested fungicide, values for duration of plant survival and shoot and root fresh weight usually were numerically larger but not significantly different for chile peppers receiving water as needed compared to those flooded for 48 h every 2 weeks. The potential and relative value of azoxystrobin, dimethomorph, fosetyl-Al, and fluazinam as chemical management tools for Phytophthora root and stem rot on chile pepper, in addition to mefenozem (metalaxyl), has been demonstrated.
    • Alternative IPM Programs for Management of Lepidopterous Larvae in Fall Lettuce

      Palumbo, John; Byrne, David N.; Baciewicz, Patti (College of Agriculture, University of Arizona (Tucson, AZ), 2000-08)
      For a third year, a large block experiment was conducted at the Yuma Ag Center to compare the field performance of several lettuce IPM programs for control of lepidopterous larvae. Conventional, Reduced -risk , Bio-based and Modified IPM spray regimes were applied to control beet armyworm, cabbage looper and Heliothis species throughout the fall growing season. Differences in populations of total larvae among the treatments, relative to insecticide treatments and timing of application were observed at various times during the season. In general, the Conventional, Reduced -risk and Modified IPM approaches provided the most consistent control of lepidopterous larvae following each application. Harvest data showed that the spray regimes had a significant influence of head lettuce yield or quality. Maturity and quality were significantly reduced in the untreated control. An economic analysis shows that net returns varied widely among the management programs at different market prices. In conclusion, this study provides a strong data base to support the need for the development of experimental and biorational insecticide products as alternatives to conventional management programs in desert lettuce production. In addition, it demonstrates the dependance of IPM programs on a broad range of plant protection chemicals and control tactics.
    • Melon Variety Trial

      Clark, L. J.; Walser, R.; Carpenter, E. W.; Byrne, David N.; Baciewicz, Patti (College of Agriculture, University of Arizona (Tucson, AZ), 2000-08)
      Seven cantaloupe varieties and two Honeydew melon varieties were grown in a replicated small plot trial on the Safford Agricultural Center in 1998. Varieties were picked regularly during the growing season. Yields are shown in tabular form to indicate how each variety performed during the season.
    • Squash Variety Trial

      Clark, L. J.; Walser, R.; Carpenter, E. W.; Byrne, David N.; Baciewicz, Patti (College of Agriculture, University of Arizona (Tucson, AZ), 2000-08)
      Five Zucchini varieties and four yellow crook/straight-necked squash were grown in a replicated small plot trial on the Safford Agricultural Center in 1998. Varieties were picked regularly during the growing season. Yields are shown in tabular form and also graphically to indicate how each variety performed throughout the season.
    • Screening New Herbicides for Weed Control in Head and Leaf Lettuces and Broccoli

      Umeda, Kai; Byrne, David N.; Baciewicz, Patti (College of Agriculture, University of Arizona (Tucson, AZ), 2000-08)
      In preemergence (PREE) herbicide testing, all three lettuces, head, romaine, and red leaf, exhibited some tolerance to carfentrazone, sulfentrazone, flumetsulam, rimsulfuron, and thifensulfuron while giving effective weed control. In postemergence (POST) testing, cloransulam and flumetsulam controlled weeds at the lowest applied rates while lettuces were safe to cloransulam at 0.01 lb AI/A and flumetsulam at 0.03 lb AI/A. Imazamox was safe on lettuces at 0.01 lb AI/A and controlled weeds at 0.007 lb AI/A. For broccoli, sulfentrazone, fluroxypyr, and thifensulfuron applied PREE demonstrated reasonable safety and weed control. Cloransulam, flumetsulam, and fluroxypyr applied POST on broccoli exhibited adequate crop safety and good weed control.
    • Herbicide Screen for Melons

      Umeda, K.; MacNeil, D.; Lund, N.; Roberts, D.; Byrne, David N.; Baciewicz, Patti (College of Agriculture, University of Arizona (Tucson, AZ), 2000-08)
      Seventeen herbicides recently gaining registrations in corn, soybeans, or other major crops were evaluated in screening tests for potential use in melons. In a preemergence herbicide screening test, flumioxazin, dimethenamid, halosulfuron, and s-metolachlor demonstrated melon crop safety at rates higher than rates for effective weed control. In a postemergence screening test, halosulfuron and rimsulfuron gave acceptable weed control with adequate crop safety. Flumetsulam and thifensulfuron appeared to offer some acceptable weed control with a very narrow margin of crop safety. Herbicides that did not offer adequate melon crop safety or acceptable weed control in the screening tests were carfentrazone, sulfentrazone, cloransulam, flumiclorac, fluthiamide/metribuzin, imazamox, isoxaflutole, triflusulfuron, primisulfuron/prosulfuron, and clomazone.
    • Lettuce Variety Trial

      Clark, L. J.; Walser, R.; Carpenter, E. W.; Byrne, David N.; Baciewicz, Patti (College of Agriculture, University of Arizona (Tucson, AZ), 2000-08)
      Eleven head lettuce varieties and four leaf lettuce varieties were grown in a replicated small plot trial on the Safford Agricultural Center in 1998. Desertgreen variety of head lettuce from Harris Moran produced a crop with the best head weight, size and firmness rating. Premiere variety followed closely behind. Of the leaf lettuce varieties tested, Saguaro Romaine produced the best quality and quantity product. Per acre yields are calculated for each variety in the study.
    • Aphid Control in Cabbage Study

      Umeda, K.; MacNeil, D.; Byrne, David N.; Baciewicz, Patti (College of Agriculture, University of Arizona (Tucson, AZ), 2000-08)
      Aphistar provided the quickest reduction of the aphids after one application and continued residual control for up to 14 DAT-2. Following a second application and reduction of aphids, Pirimor, Provado, Fulfill, Actara, and Metasystox-R provided a varied degree of residual control of aphids between 5 and 14 DAT-2. A comparison of Fulfill rates indicated that the two rates were equally effective at 5 DAT-2 but the lower rate did not offer as long residual control compared to the higher rate. Endosulfan was moderately effective and did not provide acceptable control after 1 week.
    • Comparison of Neonicotinoid Use Patterns for Silverleaf Whitefly Management in Melons and Broccoli

      Palumbo, John C.; Muliis, Clay Jr.; Reyes, Francisco; Amaya, Andreas; Lesdesma, Luis; Cary, Lisa; Byrne, David N.; Baciewicz, Patti (College of Agriculture, University of Arizona (Tucson, AZ), 2000-08)
      Studies were conducted in 1998 and 1999 to evaluate three neonicotinoid insecticides for control of silverleaf whiteflies in melons and broccoli plots at the Yuma Agricultural Center. The results of these studies demonstrate that these insecticide uses offer vegetable growers management alternatives for controlling whiteflies comparable to what they have experienced with Admire®. In our spring trials, we applied Platinum® at planting, as a split application, and as a sidedress application. All methods provided whitefly efficacy similar to that provided by Admire. However, the split and sidedress applications provided more consistent residual control than Platinum applied at planting. Because of the mobility of the product in the soil, growers may have more flexibility for effectively applying the material post-planting. In addition, Assail, was applied as a foliar spray at various densities. Under spring growing conditions, applications of Assail provided significant whitefly control when initiated at low densities. Under high whitefly densities on fall melons and broccoli, application of Assail was capable of significantly reducing existing immature populations. These evaluations suggests that Platinum and Assail may be promising alternatives to Admire. We presume that it may allow growers to use the product in a responsive manner as a side dress (Platinum) or as a foliar (Assail) rather than having to rely on prophylactic Admire applications at planting.
    • Evaluation of Foliar Insecticides for Whitefly Control in Cantaloupes

      Umeda, K.; MacNeil, D.; Roberts, D.; Lund, N.; Byrne, David N.; Baciewicz, Patti (College of Agriculture, University of Arizona (Tucson, AZ), 2000-08)
      The pyrethroid insecticides esfenvalerate (Asana®), bifenthrin (Capture®), or fenpropathrin (Danitol®) combined with endosulfan effectively reduced whitefly (WF, Bemisia argentifolii) counts at 1 week after treatment (WAT) following each of five applications. Asana, Capture, or Danitol combined with endosulfan effectively reduced WF counts at 1 WAT following each of five applications. Danitol treated melons exhibited fewer adult WF compared to Asana or Capture at most of the rating dates at 6 days after treatment (DAT) of each of the applications and also at 11 DAT of the last application. A single application of buprofezin (Applaud®) treatments or pymetrozine (Fulfill®) effectively reduced WF nymphs for 18 to 24 DAT and adults were reduced for 18 DAT. Fulfill exhibited a rate response where the higher rate reduced WF counts more than the lower rate.