Spatiotemporal Dynamics of Bemisia tabaci MEAM1 (Hemiptera: Aleyrodidae) in Commercial Soybean Crops

Spatiotemporal dynamics studies of crop pests enable the determination of the colonization pattern and dispersion of these insects in the landscape. Geostatistics is an efficient tool for these studies: to determine the spatial distribution pattern of the pest in the crops and to make maps that represent this situation. The aim of this study was to determine the spatiotemporal distribution of B. tabaci adults and nymphs in commercial soybean crops from planting to harvest using geostatistics. Infestation by adults and nymphs of B. tabaci started between 30 and 50 days after the emergence of the plants. The maximum population density of ten adults per plant and two nymphs per leaf was registered between 90 and 101 days after plant emergence. The colonization of soybean plants by B. tabaci may be divided into three stages: beginning infestation (at the outermost parts of the crop), whole area colonization, and dispersion colonization (when the whole crop area is infested). The density of adult insects was positively correlated with rainfall and relative humidity. Wind speed positively affected the dispersion of adult whiteflies. The distribution pattern of B. tabaci in the soybean crop was aggregated.