Rice is staple food for more than half of the world population but the pest insects play havoc with the crop and in case of severe infestation failure of the crop occurs. Amongst these notorious insect pests, leaffolder and stem borer attained their peak occurrence in September while whitebacked planthopper, green leafhopper and white leafhopper in October. However, the maximum and minimum temperature (except stem borer having positive effect) and rainfall (except green leafhopper having positive effect) were proved vital for bringing a change in the population of green leafhopper, leaffolder, stem borer, whitebacked planthopper and white leafhopper. Similarly, relative humidity has shown a positive response on their population. Curaterr 3G @ 10 kg/ acre gave effective control of leaffolder who attained the economic threshold level of 4 larvae/ hill than Asomido 60SL @ 400 ml/ acre under the calendar-based schedule as compared to need-based control with more yield and better cost-benefit ratio (1:5.53). The present findings will be helpful in understanding the behavior of the captioned insect pests in relation to their environment and ultimately their control.