Location: Southern Insect Management Research
Project Number: 6066-22000-084-000-D
Project Type: In-House Appropriated
Start Date: Jul 13, 2015
End Date: Jul 12, 2020
Objective:
Objective 1: Develop new approaches for the control of noctuid and hemipteran pests of southern row crops, integrating multiple control tactics into integrated pest management systems.
Sub-objective 1.A: Develop new strategies that reduce numbers of insecticide applications on soybean and cotton that are not economically justified.
Sub-objective 1.B: Develop new approaches for the control of insect pests of sweet potato.
Objective 2: Minimize negative effects of integrated pest management systems on pollinators and other beneficial arthropods.
Sub-objective 2.A. Determine the impact of current insect management strategies in corn, cotton, sweet potatoes, and soybean on populations of pollinators and beneficial insects.
Sub-objective 2.B. Examine the acute toxicity, synergistic/antagonistic interactions, and sub-lethal impacts of commonly used pesticides on honey bees using bioassay, biochemical, and molecular approaches.
Objective 3: Improve pest risk assessment by determining environmental influences that affect populations of important insect pests of southern row crops with emphasis on bollworms, tobacco budworms, tarnished plant bugs, stink bugs, and soybean loopers.
Objective 4: Develop methods to measure and manage insecticide resistance of pest populations of southern row crops with emphasis on bollworm, tobacco budworm, tarnished plant bug, and stink bugs.
Sub-objective 4.A. Measure levels of insecticide susceptibilities of tarnished plant bugs, bollworms and other important insect pests of southern row crops through laboratory bioassays.
Sub-objective 4.B. Develop within-field bioassays to determine insecticide susceptibilities of key pests of southern row crops.
Sub-objective 4.C. Examine the impact and sensitivity of resistance management options for major insect pests of southern row crops through simulated modeling.
Approach:
Insect management guidelines are generally static from year to year regardless of crop prices, costs of insecticides and yield potential of the crop. We plan to summarize published information for bollworm, tarnished plant bug, and stink bugs and develop economic injury level probability distributions using Monte Carlo simulations. On-farm field evaluations across the Mississippi Delta will evaluate economic returns and environmental sustainability of different insecticidal control strategies in soybean and cotton. Commercially available and experimental sweet potato varieties will be planted annually and the economic impact of insect and nematode control in sweet potato will be examined. The impact of current insect management strategies in southern row crops on populations of pollinators and beneficial insects will be examined in production fields. The surrounding habitats of each field will be documented for plant community composition, focusing on blooming plants that may be of interest to pollinators. Each of these fields will be sampled using a combination of sampling techniques. Community structure will be compared between cropping systems, and related to insecticide applications. We plan to evaluate acute and sub-lethal toxicities and synergistic/antagonistic interactions of honey bees to commonly used pesticides. An examination of gene regulation in honey bees associated with immunity, adaptation, detoxification, digestion/metabolism, and stress-related genes will be conducted after exposure to pesticides with techniques such as real-time PCR , RNAseq or microarrays. Hemipteran and lepidopteran phytophagous pest populations are highly mobile within the landscape and use a variety of weeds and crops as host plants. To examine landscape influences on these insects, the landscape composition surrounding historic and current collection locations will be quantified using Cropland Data Layers (CDLs). Using these CDL layers, buffer zones will be generated around locations. Output data will be tabulated to produce total area of habitat type included within each buffer area and will be related to data collected on insect populations using appropriate statistical analyses. SIMRU will continue to examine susceptibilities of hemipteran and lepidopteran insect pests collected from locations across the Mississippi Delta with a variety of assay methods which may include topically treated diet, residual contact bioassays, glass vial bioassays and a feeding contact assays using floral foam. Insects from original collections will be preserved for molecular analysis using genetic markers. When colonies of any of the pest groups have reduced susceptibility to the tested insecticides, efforts will be made to preserve the colony under a selected and non-selected sequence of exposures to the insecticides of interest We propose to develop rapid bioassays to predict the effectiveness of an insecticide application on a real field population of insects. To examine predictive values of laboratory assays on actual field populations, a plot sprayer will be used to deliver a range of formulated product rates on targeted insects.
