Submitted to: National Entomological Society of America Annual Meeting
Publication Type: Abstract Only
Publication Acceptance Date: 8/31/1999
Publication Date: N/A
Technical Abstract: The feeding and digestive processes of phytophagous heteropteran species significantly impacts the interaction of the insect with its plant hosts. We investigated the ingestion, absorption, degradation, excretion, and salivation of GFP by the western tarnished plant bug, Lygus hesperus. Analysis of GFP, administered through the diet, indicated that L. hesperus is a discrete intermittent feeder, with a maximum volume of ca. 10 l for each meal. The time from ingestion to excretion is about 3 hr, while GFP was found in the hemolymph and saliva at 5 hr and 6 hr, respectively. Brightfield and fluorescence images showed that GFP bound to the anterior part of the midgut and posterior part of the hindgut and caused disruption of epithelial cells in second instar nymphs. However, no effect (binding or tissue disruption) was observed in adult females. Changes were noted in the composition of the acidic and basic proteins in the hemolymph with the addition of GFP to the diet. Electrophoretic analysis revealed that fecal material from insects fed diet containing GFP had a higher composition of dietary proteins than fecal material from insects fed diet alone. Hence, incorporation of GFP in the diet may interfere with the digestion and absorption of dietary proteins.