Spatial Distribution of Adult Populations of Bactericera cockerelli Sulc.(1), in the Cultivation in Tomatillo (Physalis ixocarpa Brot.)

摘要

Tomatillo (Physalis ixocarpa Brot.) is grown throughout Mexico, United States, and Central America. Recently the production of tomatillo has suffered economic losses of 70 to 80% due to floral abortion, and yellowing by the presence of phytoplasma transmitted by the insect Bactericera cockerelli Sulc. Alternative control of the psyllid lacked effectiveness because it's spatial distribution in tomatillo fields was unknown. This study aimed to use geostatistics to determine the spatial distribution of adults in four plots of tomatillo. The experimental variogram was determined to conform to a theoretical model (spherical, exponential, or gaussian) through Variowin 2.2 programs. The adjustment was validated with the method of cross-validation and maps aggregation pest obtained through Kriging with Surfer 9.0 program. The short-term temporary space stability of the pest was determined by testing Cramer-von Mises and the index SADIE association. The results showed that populations of B. cockerelli have a distribution of aggregate type, which was corroborated by density maps. Infestations were not present in 100% of the surface of the experimental plots, which is important to know because control measures can be directed to specific areas of infestation.