Joyce G. Latimer, Ronald D. Oetting, and Paul A. Thomas
Amanda J. Vance, Patrick Jones, and Bernadine C. Strik
·ha −1 ) ( Table 3 ) using either a backpack sprayer (as previously described) at a concentration of 0.05% Ca (748 L·ha −1 of water) or at a concentration of 0.16% Ca using an electrostatic sprayer (215 L·ha −1 of water; On Target Spray Systems, Mt
Celeste Welty, Sandra Alcaraz, and H. Erdal Ozkan
Insecticide application techniques were evaluated to find the most effective way to spray contact insecticides to control aphids on leaf crops under field conditions. A hydraulic boom sprayer was tested with several nozzle types, nozzle positions, and pressures, and compared with an electrostatic sprayer and a controlled droplet applicator (CDA). Spray deposition in the canopy and drift were evaluated with moisture-sensitive cards. Trials were conducted on collards and red leaf lettuce in 1989, mustard greens in 1990, and turnip greens in 1991. Green peach aphid [Myzus persicae (Sulzer)] was the major species in all trials. Among hydraulic boom treatments in all trials, aphid control was not significantly different when insecticide applied at 60 psi (414 kPa) was delivered by hollow cone, twin flat-fan, or standard flat-fan nozzles mounted directly on the boom. In most trials, hollow cones were more effective when mounted on drop pipes and directed sideways into rows than when mounted on the boom and directed over rows. Hollow cone nozzles used at 150 psi (1035 kpa) vs. 60 psi did not control aphids significantly better, but higher pressure caused significantly more drift. Contact insecticide applied by an electrostatic sprayer controlled aphids somewhat less satisfactorily than by a conventional hydraulic sprayer. Insecticide applied by a CDA controlled aphids the same as by a hydraulic boom sprayer but with slightly less drift. The desired objective of maximum aphid control, good coverage of downward-facing surfaces in the canopy, and minimum drift was most consistently provided by the hydraulic boom sprayer with hollow cone nozzles on drop pipes directed sideways into the canopy using a pressure of 60 psi.
Salvador Vitanza, Celeste Welty, Mark Bennett, Sally Miller, and Richard Derksen
The impact of pesticide application technology and crop stand density on bell pepper production was evaluated in a series of field trials, during 2004 and 2005, at the North Central Agricultural Research Station, Fremont, Ohio. In 2004, one trial tested three sprayers, at a speed of 8 and 4 mph, using insecticides at half the recommended rate and one treatment at full rate. Sprayers evaluated included an air-assisted electrostatic sprayer, a Cagle sprayer equipped with AI-11005 or AI-110025 nozzles, and an air-blast sprayer with XR-1003-VS or XR-110015-VS nozzles. In 2005, one experiment tested the interaction of two application technologies, three planting distances within row, and single vs. twin rows. Another experiment compared the Cagle sprayer (with TJ60-11003 or AI-110025 nozzles) and the airblast sprayer (with XR-110015-VS nozzles), at a speed of 4 mph, and insecticides at half the recommended rate. In 2004, the Cagle sprayer with air-induction nozzle, half rate, at 8 mph obtained the highest fruit yield. There was not significant improvement in European corn borer control by applying insecticides at full rate with the Cagle sprayer and all treatments achieved significantly better bacterial soft rot control than the untreated control. In 2005, the trials were terminated early due to crop destruction by Phytophthora capsici. Red fruit weighed less at high than at medium or low plant stand densities. Clean yield of red fruit was significantly greater in single rows than in twin rows. Marketable yield of green fruit was greater using the TJ60-11003 than using the AI-110025 nozzles.
Mathews L. Paret, Aaron J. Palmateer, and Gary W. Knox
deposition of too much photocatalytic material on the leaf surface of plants over multiple applications using a conventional sprayer. We noticed a similar issue in our studies on tomato, which was resolved by the use of an electrostatic sprayer for