Pest Management in Horticultural Ecosystems

Studies were carried out at Citrus Research Station, Tirupati to record the extent of natural parasitisation of the larvae of citrus butterfly, Papilio sp. infesting sweet orange (cv. Sathgudi) and acid lime (cv. Balaji). During the period of study, three braconid parasitoids, viz., Apanteles pailionis Viereck, Apanteles sp. and Bracon hebetor were observed as larval parasitoids of citrus butterfly. The parasitisation was negligible on sweet orange and acid lime in the months of June, July, 2002 and April, May, 2003 which was due to absence of larval population. Peak parasitisation increased with peak infestation of the citrus butterfly and highest rate of parasitisation (33.33 to 82.45%) was observed on sweet orange during the months of October 2002 to January 2003 and on acid lime, highest rate of parasitisation (38.46 to 77.77%) was observed during the months of November 2002 to January 2003. The extent of natural parasitism was observed to be negatively correlated with maximum and minimum temperature.