Seasonal incidence of insect pests on rice and impact of various abiotic factors on their incidence

Abstract

The incidence of brown plant hopper (Nirparvata lugens (Stal.) was started from 32nd MW i.e. first week of September with its peak during 42nd MW i.e. third week of October. The continuous increase in population of brown plant hopper was recorded since 36th MW to 42nd MW. Incidence of brown plant hopper showed significant negative correlation with rainfall (r = -0.488), morning relative humidity (r = -0.614) and positive correlation with maximum temperature. The incidence of stem borer was commence during 34th MW and increased gradually 37th MW. The incidence of leaf folder was initiated in 37th MW and reached to its peak in 40th MW. The correlation analysis regarding leaf folder and stem borer revealed a significant positive correlation with maximum temperature and significant negative correlation with evening humidity, respectively.