Seasonal Dynamics of Insect Community Structure in Texas High Plains Cotton

Insect pests are one of the limiting factors in cotton production systems in the Texas High Plains. The potential insect damage to a crop is a combined effect of the entire insect community rather than of the effect of a single pest species. Knowledge of the seasonal dynamics of the insect community structure in cotton is essential for the development of ecologically intensive pest management strategies for cotton. The effect of cotton phenology in the insect community structure in Texas High Plains cotton had not been well characterized. Therefore, a season-long species diversity and community structure characterization was performed in a furrow-irrigated cotton field located near Lubbock in 2007. Insect samples were collected weekly from 300 row-feet of cotton using a blower sampler for 11 weeks during the growing season. The seasonal pattern of species composition, richness, and diversity of the insects inhabiting the High Plains cotton field was determined. The seasonal change in insect community structure in cotton was also determined. Insect diversity was very low during the early vegetative growth stage. Species diversity increased as the foliage and crop canopy increased and the highest species diversity was observed during the cotton blooming stage. The community structure of the insect fauna also changed with the changes in the crop phenology. Information on the community structure dynamics will be useful in development of holistic approaches of pest species management by managing the insect community as a whole.