2013 Annual Report
1a.Objectives (from AD-416):
Quantify the impact of the introduction of bioenergy feedstock crops (canola and switchgrass) on the pest, natural enemy and pollinator complex in the Arkansas and Oklahoma agroecosystem.
1b.Approach (from AD-416):
We will study various aspects of arthropod dispersal in complex agroecosystems containing potential biofuel crops using protein mark-capture methods.
This Reimbursable Agreement is in support of Objective 3, "Characterize flight behavior and dispersal of insect pests and natural enemies; elucidate relationships among landscape structure, pest and natural enemy biology and dispersal behavior", of the inhouse parent project. Sustainability of the nation’s biofuel feedstock production systems relies on the selection and production of energy crops that efficiently generate biomass without disrupting existing agricultural systems. Pest and beneficial organisms will certainly occur in these feedstock crops, but the net effect of these crops on population dynamics of pests and beneficials within the overall production system is unknown. Biofuel crops may serve as a nursery (source), producing pests or beneficial organisms that subsequently move to other crops, or may trap or attract these organisms from surrounding crops, thereby serving as a sink. These source/sink relationships can be beneficial or deleterious to the feedstock crop or to the surrounding agricultural production systems. The second year of a multi-year mark-capture study was completed in both Kansas and Oklahoma. Researchers from Oklahoma State, Kansas State, Arkansas, and USDA, ARS, Arid Land Agricultural Research Center (ALARC) in Maricopa, Arizona, are examining the impact of biofuel crops on areawide population dynamics of insect pests, natural enemies and pollinators. Specifically, we are studying these source/sink relationships in adjacent canola, switchgrass, and pasture fields by identifying the arthropod complex that inhabits them. In addition, we are determining the extent and timing of the movement of the important pest and beneficial species among the biofuel feedstock and conventional crops in the landscape using specific protein markers. To accomplish this, we sprayed large areas of each crop, each with a unique protein marker. This, in turn, marked the resident arthropod population. Sites at selected locations within the study area were then sampled for insects multiple times over the growing season, and the collected insects were assayed for the presence of each of the protein markers. This information indicated the origins of the collected insects, and the distances that they travelled. To date, we have assayed over 48,000 field-collected insects for the presence of each of the three protein marks (144,000 assays). The data generated by our research team will provide insight into the risks or benefits associated with the integration of large plantings of canola and switchgrass into established agricultural landscapes.