Sunday, December 9, 2007 - 9:17 AM
0031

Impacts of disturbance on soil-dwelling microarthropod communities and entomopathogenic nematodes in winter wheat in Oklahoma

Trisha Dubie, trishd@okstate.edu and CM. Greenwood, carmen.greenwood@okstate.edu. Oklahoma State University, Entomology and Plant Pathology, 127 Noble Research Center, Oklahoma State University, Stillwater, OK

Soil communities and their relationship to soil quality and nutrient cycling have not been thoroughly explored with respect to agricultural practices. Arthropods and other organisms found in the soil contribute greatly to the soil quality and success of cultivated plants. Disturbance, such as tillage has an effect on the species complex contained in a given area thus having an effect on the soil quality in that area. Examining and comparing the species complex in conventionally tilled winter wheat plots to winter wheat plots that have not been tilled could provide valuable information on the effect of decades of tillage in the state of Oklahoma and elsewhere. Microarthropods are vital to the decomposition of organic matter and nutrient turnover in the soil. Changes in the environment such as tillage and other types of disturbance will alter these microarthropod assemblages. Agroecosystems that have not been tilled contain an entirely different species complex than areas that have been tilled. Studies on no-till agroecosystems have shown greater invertebrate species richness, greater soil organic matter, and greater resilience in the system. The soil community also contains many naturally occurring entomopathogens. These pathogens can be used as an effective biological control method against soil dwelling agricultural pests. Much like the variance in soil arthropod species, the types of entomopathogens present may also vary between conventional till and no-till systems.



Species 1: Mesostigmata Ascidae Protogamasellus massula
Species 2: Rhabditida Steinernematidae Steinernema carpocapsae