Demographic parameters of Helopeltis antonii Signoret (Heteroptera: Miridae) on neem, cocoa and henna

Helopeltis antonii is a polyphagous pest causing considerable economic damage for cashew in South India. Relative multiplication of H. antonii was studied on its three important alternate host plants; neem, cocoa and henna. Life tables and population parameters for the mirid were constructed based on unlimited food condition and a natural enemy-free environment. The preoviposition period was between 19 to 23, 20 to 23 and 17 to 21 days of pivotal age, respectively on neem, cocoa and henna. The survivorship (lx) of H. antonii for three hosts shows similar pattern with high mortality occurring during egg, nymphal growth particularly in the early instar which then gradually decreases throughout the life span. The life expectancy (ex) of H. antonii declined gradually with the advancement of growth development in all three host plants. The net reproductive rate indicating the total female births (Ro) was 43.8, 45.9 and 16.1; the population increased with a intrinsic rate (rm) of 0.1425, 0.1505 and 0.1218: and finite rate (λ) of 1.1531, 1.1624 and 1.1295 female per day and a generation was completed in 26.52, 25.42 and 22.81 days on neem, cocoa and henna, respectively. Percent contribution of different growth stages in stable age-distribution revealed that the immature stages (eggs and nymphs) contributed maximum.   Key words: Helopeltis antonii, neem, cocoa, henna, life table.