Effect of Aerial Application Parameters Simulated on a Spray Table on Efficacy of Deposits of Commercial Insecticides Recommended for Control of Tobacco Budworm/Bollworm, Fleahoppers, Green Stink Bugs, Lygus and Aphids on Cotton and Other Crops
| Problem: | With the success of the boll weevil eradication program in Texas and in other areas of the cotton belt, expectations are that cotton fleahoppers, Lygus and green stinkbugs will become key cotton pests. The cause appears to relate primarily to the absence of broad spectrum insecticide use for control of boll weevil. This coupled with the decrease in use of insecticides for controlling bollworm/tobacco budworm because of increased plantings of Bt cotton varieties have really set the stage for problems with sucking insects. Cotton aphids will likely continue to be key pests. Although there has been a decrease in use of insecticides for control of tobacco budworm and bollworm because of Bt cotton planting, there continues to be a need for insecticides to control them in nonBt cotton as well as on Bt cotton, but to a more limited extent. Numerous insecticides, some old standards as well as many new insecticides, are recommended for control of sucking insect pests on cotton; however, because these sucking insects have only been recently recognized as important pests and many of the recommended insecticides are relatively new, there is a real need to evaluate the effect of aerial application parameters on efficacy of old and new insecticides. Insecticidal control of tobacco budworm and bollworm with the newer insecticides continues to be a major concern. |
| Objective: | Determine effects simulated on a spray table of aerial application parameters such as spray rate, nozzle (type, size, and orientation), etc. and active ingredient concentration on efficacy of deposits (droplet size spectrum and density) of selected insecticides on cotton and other crops for controlling adult and immature fleahoppers, aphids, Lygus, and green stink bugs and tobacco budworm/bollworm larvae. |
| Approach: | Considerable information is available on the effect of aerial application parameters on deposition (droplet size and density) on cotton and other crop plants. Additional field evaluations will be conducted as necessary to obtain deposition information. A laboratory spray table apparatus will be calibrated to spray potted cotton and other crop plants to provide deposits of insecticides representative of different aerial application parameters. Adult and immature wild fleahoppers, Lygus and green stinkbugs collected from favorite host plants or trapped in blacklight traps will be confined on the treated plants and mortality will be determined based on time of exposure. For evaluations with immature fleahoppers, Lygus, and green stink bugs, adults will be confined on untreated plants so that oviposition will occur. Infestations of immatures will be allowed to develop on the plants. If this is not possible, short term rearing of immatures from field-collected adults will be done to conduct the tests. Cotton aphids will be infested on untreated plants from field collections or cultures maintained on seedling cotton. Tobacco budworms and bollworms collected from the field as adults or larvae will be allowed to oviposit and larvae hatching from the eggs will be used to infect plants. Infested plants will then be treated and counts made on untreated and treated plants to determine mortality.over time corrected for check mortality. |
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Accomplishments: |
This is a new research project; however, much of the previous research conducted by Unit members on the effect of aerial application parameters on insecticide deposition on cotton plants will be relied on extensively to pattern the deposition on cotton and other crop plants. Spray table tests with various insecticides for control of aphids, stink bugs and thrips have already been conducted and show the feasibility of conducting these studies |
Juan D. Lopez