Behavior of pomegranate fruit borer, Deudorix isocrates (Fab.) (Lepidoptera: Lycaenidae)

Abstract

Deudorix isocrates is one of the serious pests of pomegranate, Punica granatum. The present study was undertaken as behavioral understanding of pests has crucial significance in pest management. The present study deals with larval behavior like searching period, selection of site to enter in the fruit, increase in size of entrance hole, selection of sites for pupation and adult behavior with respect to oviposition and fecundity. It was found that the gravid female rarely lays egg on a flower, the twigs and the underside of leaves. The calyx end of fruit is the most preferred site of egg laying (68.65%) than other parts like the lower half (11.56%), the stalk base (8.31%), the upper half (7.49%) and the middle region (3.97%) of the fruit. After hatching, the most of the neonate larvae (32%) consumed 16 to 30 minutes of period to search suitable site to enter in the fruit. The searching period ranges between less than 15 minutes (6%) to more than 4 hours (2%) in the rare cases. The lower half of the fruit is the most suitable site for larval entry (57.77%) while the stalk base region of the fruit was rejected for larval entry (0%). The larvae cut the fruit rind to increase dimeter of entrance hole from the early to the late instar stages. It was found 0.84 mm in the first instar, 1.43 mm in the second instar, 2.68 mm in the third instar and 5.76 mm in the fourth instar stage of larva. While studying pupation sites it was revealed that maximum number of larvae (62.60%) pupated inside the fruit, least number (1.56%) of larvae pupated on the fruit surface. 2.43% of the larvae pupated inside the calyx while 33.39% of the larvae pupated somewhere else.