Effect of temperature, relative humidity and food material on the biology of Sitophilus oryzae Linnaeus and Rhizopertha dominica Fabricius (Coleoptera: Curculionidae and Bostrichidae).

Abstract

A study of the developmental period and mortality of Sitophilus oryzae and Rhizopertha dominica was carried out at temperatures of 18°C, 25°C and 30°C and 50%, 60%, 75% and 80% r.h. levels. Observations from the above study revealed that time taken by Sitophilus oryzae to become adult at 18°C 80% r.h. and by Rhizopertha dominica at 18°C 75% r.h. was maximum. Mortality was minimum in Sitophilus oryzae at 25°C 75% r.h. and in Rhizopertha dominica at 25°C 60% r.h. in both wheat and maize. It was further observed that mortality was higher in case of maize than in wheat.