ABSTRACT

Sweep net sampling was used to determine species composition, distribution and abundance of Lygus bugs in the northern Texas Rolling Plains. Samples were taken in 15 counties during May and July in 2001 and 2002. Samples taken in May were from alfalfa, vetch, and blooming roadside weeds, and samples taken in July were from alfalfa and cotton. Of the 409 Lygus spp. identified from 20,646 sweeps, 15.9, 32.3, and 51.8% were L. lineolaris (Palisot De Beauvois), L. hesperus Knight, and L. elisus Van Duzee, respectively. Lygus lineolaris was present in low numbers throughout the Rolling Plains, while both L. hesperus and L. elisus were most numerous in the northwestern region of the northern Rolling Plains. There was an apparent species ratio shift in alfalfa, and L. lineolaris was more abundant in July than in May, while L. hesperus and L. elisus were more abundant in May than in July. Sweep net sampling data taken in 1976 and 2001/2002 indicate that there has not been a significant change in Lygus abundance in cotton or alfalfa since the mid-1970's. Only 8 Lygus bugs, in 10,675 sweeps (0.07/100 sweeps), were detected in cotton in only four counties, and there was no evidence to suggest that Lygus bugs pose a current threat to cotton production in the Texas Rolling Plains.