Spatial pattern of infestation risk and management of the invasive brown marmorated stink bug in soybeans
Recent increases in populations of the invasive brown marmorated stink bug (BMSB) Halyomorpha halys (Stål 1855) on farms of Mid-Atlantic United States has resulted in widespread economic losses. The ability of farmers to efficiently control BMSB by adjusting local farm practices requires knowledge of its spatial distribution within fields and across large landscapes. Also, prevailing environmental factors and regional land use may inhibit or
support outbreaks by impeding or facilitating connectivity of BMSB among fields. However, studies investigating the spatial distribution of BMSB in grain crops, throughout the season and at multiple spatial scales, are not available. Also, the influence of land uses, crop characteristics and environmental conditions on BMSB distribution patterns is not well understood. Employing a combination of field sampling, Geographic Information Systems (GIS) and spatial analysis techniques, the proposed project will – a) suggest spatially targeted timing and intensity of pest treatment solutions by documenting BMSB densities in soybean fields at different spatial scales for the entire season; b) inform manipulation of the phenology, placement, and suitability of types of vegetation and/or crops to counteract BMSB invasion by investigating influence of habitat, crop and environmental characteristics on BMSB densities in soybean fields; and c) provide a table of BMSB infestation risk factors and in
-field distribution associated with specific farmscapes, and identify areas vulnerable to higher infestation of BMSB. Thereby this research aims to inform field and landscape level pest management strategies and threat potentials of BMSB in soybean crops of Mid-Atlantic region in the United States.
The specific objectives of this research project are:
1. To assess the influence of adjacent habitats on spatio-temporal differences in densities of BMSB in soybean field edges.
The specific question addressed is
How do adjacent habitat types (woodlots, habitations, corn, and non-crop open areas) influence BMSB densities at different distances into soybean field from the edge (movement into field) throughout the crop season?
2. To assess the influence of field level environmental and crop characteristics on the spatio-temporal differences in densities of BMSB within adjacent corn-soybean fields;
The specific questions addressed are
a. How do the spatial distributional densities of BMSB vary within adjacent corn and soybean fields over the season?
b. How do the field level environmental and crop characteristics influence the spatio-temporal variation in BMSB densities?
3. To assess the influence of land use at multiple scales and environmental factors, on the landscape scale differences in relative abundances of BMSB in soybean fields.
The specific questions addressed are
a. How does the spatial distributional relative abundance of BMSB in soybean vary over the entire study area?
b. How do different landscape, environmental, and topographic variables influence observed stink bug abundances at different spatial scales?
4. To provide a table of infestation risk factors and in-field distribution patterns associated with specific farmscapes surrounding soybean fields and identify soybean production areas with higher vulnerability to outbreak of BMSB.
While the project is primarily designed to investigate the distributional variation in stink bug populations, the focal spatial scale is different across each objective. Objective 1 concentrates on densities at field edges, while Objective 2 focuses on entire field scale densities and Objective 3 samples the relative abundances across large landscape scale. Each objective address land use influences on the pattern of BMSB populations. Overall, these objectives intend to quantify the variation in densities of BMSB, at different spatial scales, and examine the factors influencing the populations. Objective 4 is dependent on the inferences from preceding objectives, and will be developed as a component with consolidated synthesis of results.
Field work for this research project will commence in May 2013.