Spatial distributions of thrips in cotton

The degree of aggregation of thrips and injury in cotton and their spatial association with NDVI and soil apparent electrical conductivity (ECa) was determined using the Spatial Analysis by Distance IndicEs analyses (SADIE). Significant (P < 0.05) aggregation occured in four out of 24 analyses for adult thrips (17%), four out of 24 analyses for immature thrips (17%), and two out of 15 analyses for injury (13%). Using the SADIE association tool, NDVI was associated with adult thrips in two out of 20 paired datasets (10%), with immature thrips in three out of 20 paired datasets (15%), and with thrips injury in one out of 14 paired datasets (7.1%). Shallow soil ECa was positively associated with adult thrips in six out of 21 paired datasets (28.6%), with immature thrips in eight out of 21 paired datasets (40.0%), and with thrips injury in eight out of 14 paired datasets (57.1%). Soil ECa may have a greater potential for site-specific management of thrips in cotton than NDVI, particularly in the Coastal Plain of the southeastern United States, where soil types are highly variable.