SUSCEPTIBILITY OF SOYBEANS TO DAMAGE BY <i>NEZARA VIRIDULA</i> (L.) (HEMIPTERA: PENTATOMIDAE) AND <i>RIPTORTUS SERRIPES</i> (F.) (HEMIPTERA: ALYDIDAE) DURING THREE STAGES OF POD DEVELOPMENT

Abstract

Abstract Caged Davis soybean plants were infested with Nezara viridula (L.) and Riptortus serripes (F.) (4.4 adults/m) at 3 stages of pod development in 3 experiments in 1987, 1988 and 1989. Bug feeding reduced seed yield and oil content during pod fill, but not during pod elongation or pod ripening. N. viridula reduced yields significantly in 1987 and 1988, (183 and 494 kg/ha) but R. serripes reduced yields significantly only in 1988 (353 kg/ha). Both species damaged more seeds during pod fill than during any other pod stage, but N. viridula damaged more seeds than R. serripes . Mean seed weight was reduced only during pod fill. In contrast, the mean weight of undamaged seeds increased during pod fill. This indicated partial compensation by Davis soybeans for damage caused by the above bug species at a density of 4.4 adults/m. Seed oil content, recorded only in 1988, was reduced significantly by N. viridula , but not by R. serripes .