Roundup Ready~R soybean, Glycine max (L.) Merrill, in wide-row planting systems were investigated in 1997 and 1998 in Mississippi to determine effects of the transgenic crop and glyphosate herbicide on pest and beneficial insects. Populations of adultbean leaf beetle, Cerotoma trifurcata (Forster), and threecornered alfalfa hopper, Spissistilus festinus (Say), and larvae of green cloverworm, Hypena scabra (F.), and velvetbean caterpillar, Anticarsia gemmatalis (Hübner), were not affected by genetically altered Roundup Ready soybean or by applications of glyphosate. Numbers of adult big-eyed bug, Geocoris punctipes (Say), also were not affected by the transgenic soybean but were influenced by glyphosate applications in 1 of 2 years. G. punctipes adults were not directly affected by glyphosate applications, but glyphosate indirectly influenced G. punctipes densities in 3 of 11 weeks. These effects were attributed to increased weed densities having a positive effect on G. punctipes numbers during this 3-week period. Increased numbers of G. punctipes were also found in soybeans receiving delayed applications of glyphosate compared to those receiving glyphosate sprays at recommended times in 1 of 2 years. These elevated numbers, however, were also related to higher densities of weeds. The results presented herein demonstrated that the Roundup Ready soybean system, including applications of glyphosate, had no detrimental effects on pest and beneficial insects in wide-row soybean plantings. Knowledgeof the influence of herbicide-tolerant cropping systems on the occurrence, density, and behavior of pest and beneficial insects in soybean should be beneficial in making future insect pest management decisions.
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