Histological studies were conducted on cowpea pods fed upon by the coreoid pod-sucking bugs, Anoplocnemis curvipes (Fabricius), Clavigralla tomentosicollis Stå;l, C. shadabi Dolling, Riptortus dentipes (Fabricius) and Mirperus jaculus (Thunberg). Various degrees of tissue and cellular disruption were apparent, especially in the brachysclereids. They were manifested in terms of plasmolysis, cell enlargement and cell wall disintegration depending on the coreoid species involved. The feeding site and its periphery had all the cells of the brachysclereids plasmolysed, with the parenchyma having broken cell walls in the case of A. curvipes. Riptortus dentipes and M. jaculus showed similar patterns of feeding activity but less extensive levels of damage. The Clavigralla spp., however, caused cell enlargement in the brachysclereids, and broken cell walls in both the brachysclereids and the parenchyma. Damage symptoms were observed in cells far away from the feeding sites of the bugs, suggesting the possibility of sucrase activity which has been reported to cause osmotic pump feeding in the Coreidae.

Laboratory studies with Megalotomus parvus (Hemiptera: Alydidae), feeding on seeds or pods of legumes, and on different parts of the soybean plant, Glycine max, demonstrated that nymphal survivorship, developmental time and body weight at adult emergence, and adult reproductive parameters, survivorship, longevity and body weight changes, exhibited differences depending on the food source utilized. In general, mature soybean seeds (R8 stage) were the most suitable food. The greatest nymph and adult survivorship and the greatest adult longevity were obtained from this food source. Body weight at certain ages and fecundity of females was also greater on mature soybean seeds than on the other foods. Immature soybean seeds for nymphs, and soybean pods for adults, were the second most suitable food, followed by green beans, Phaseolus vulgaris and immature lupin, Lupinus luteus seeds (for nymphs) and lupin pods (for adults); nymph and adult performance was drastically reduced on lupin seeds'pods and no nymphs survived to adult on soybean stems or leaves. On all foods tested, duration of the nymphal stages differed significantly, with the first stage being the shortest, and the fifth the longest. Females achieved significantly greater body weight than males on all foods, except on lupin pods. Results of these laboratory studies and those of field observations suggest that mature soybean seeds are the most important food source in the seasonal phenology of M. parvus.