- Agronomic: sorghum (milo), wheat, grass (misc. perennial), hay
- Animal Production: feed/forage
- Crop Production: conservation tillage, fallow
- Education and Training: display, workshop
- Natural Resources/Environment: biodiversity
- Pest Management: biological control, chemical control, cultural control, economic threshold, physical control, precision herbicide use
- Production Systems: agroecosystems
- Soil Management: soil chemistry
- Sustainable Communities: sustainability measures
Continuous monocultures, soil cultivation, and overuse of pesticides decrease the presence of natural enemies of pests in agricultural systems. Natural enemies have a regulating effect on pest populations in winter wheat, alfalfa, cotton, and sorghum in the Southern Great Plains. In Oklahoma and Texas, aphid damage results in increased pesticide applications and yield losses. Greenbugs cause heavy losses which can range from $3.8 to $135 million in grain wheat grown in Oklahoma. Regulation of pest populations by natural enemies is an essential element of integrated pest management plans (IPM). Carabid beetles are an important component of natural enemy assemblages that reduce populations of agricultural pests and consume weed seeds. Carabids react to environmental changes quickly and measurably, are relatively easy to trap, are persistent in disturbed systems, and are identified as biological control agents in scientific literature. Producers lack the necessary information regarding carabid feeding behavior and its impact on pest populations. Additionally, producers need a better understanding of carabid dispersal and colonization abilities as it relates to tillage. Sustainable agricultural practices such as diversification of agroecosystems and reduced tillage will ultimately conserve carabids that consume insect pests and weed seeds and will result in reduced pesticide applications while increasing net profits. Through the use of pitfall trapping and stable carbon isotope analyses the relationship of carabid dispersal, habitat use, and prey consumption will be evaluated. Results from this study will be presented to producers and IPM professionals via extension publications, research journals, field days, and presentations at professional meetings.
Project objectives from proposal:
It has been noted that carabids are an important component of natural enemy assemblages consuming agricultural pests. Through the use of pitfall trapping and stable carbon isotope analyses the relationship of carabid dispersal and prey consumption can be better understood (Teeri and Schoeller 1979, Peterson and Fry 1987, Ostrom and Fry 1993).
The first objective has been completed:
Quantify carabid colonization of annual crops (sorghum/winter wheat) from a semi-permanent habitat (alfalfa) as it relates to disturbance(tillage);
The second objective is in process:
Elucidate carabid dispersal powers through prey selection, diet changes within and among habitats, and larval habitat utilization;
The third objective will begin after data analysis:
Provide results of this research to producers and IPM professionals.
Objective 1: I have evaluated colonization of sorghum (conventional tillage vs. no-till) by carabids from a semi-permanent refugia habitat (alfalfa). Using standard pitfall traps spaced at specific distances within sorghum strips, we were able to calculate distances traveled over time for targeted carabid species.
Objective 2: Pending funding, I will elucidate the dispersal power of carabids between a semi-permanent refugia habitat (alfalfa) and an annual crop (sorghum) using stable carbon isotope analyses. This data coupled with results from objective one will be used to estimate carabid dispersal power among habitats and will be used to determine natal origins and therefore source of refuge.
Objective 3: Results from this study will be presented to producers and IPM professionals via extension publications, research journals, field days, and presentations at professional meetings.