HOSTPLANTTESTINGOFTHESPITTLEBUG CARYSTOTERPA FINGENSBYSTYLETPENETRATION BEHAVIOUR

Carystoterpa fingens (Walker) is an endemic xylem feeder. It was chosen as a model insect for the glassy winged sharp shooter (Homalodisca coagulata (Say)). The electrical penetration graph (EPG) technique was used to measure real-time stylet penetration and feeding behaviour of 48 adult C. fingens on four plant types, hebe (Hebe pubescens), rengarenga lily (Arthropodium cirratum), wild iris (Dietes bicolor) and cabbage (Brassica oleracea), over �2 days. EPG waveforms were recorded for �2 hours and the duration of the main penetration events (pathway, ingestion and non-probing phases) of the insects were analysed to compare host preferences. There were no significant differences in the duration of ingestion, indicating that all the plants were potential hosts for C. fingens . Insects on hebe showed the shortest non-probing time, suggesting that hebe was the most preferred host, as expected from observations in the wild.