author(s)
Edward George PJ

abstract
Three commonly used\r\norganophosphorus insecticides in the agro ecosystems namely, monocrotophos,\r\nquinalphos and dimethoate were studied for their efficacy on the life table\r\nparameters in the laboratory in a Harpactorinae reduviid predator Rhynocoris\r\nlongifrons (Stal). The LC₅₀ was calculated for all the three\r\ninsecticides for 24, 48, 72 and 96 hour durations. All the insecticides\r\nincreased their incubation period, stadial period, pre oviposition period and\r\nnymphal mortality and decreased their fecundity, hatchability and adult\r\nlongevity. Maximum reduction was noticed in the monocrotophos treated category\r\nfollowed by quinalphos and dimethoate. The Gross reproductive rate and Net\r\nreproductive rate of R. longifrons is 78.00 and 94.38 respectively which\r\nis reduced to 57.00 and 29.36, 69.00 and 34.54 and 64.00 and 31.58 respectively\r\nfor monocrophos, quinalphos and dimethoate treated category in R. longifrons.