Seasonal incidence of major insect pests of rice (Oryza sativa L.) and its correlation with weather parameters

Abstract

The present investigation was carried out to study the seasonal incidence of major insect pests of rice (Oryza sativa L.) at the Agricultural Research Farm, Institute of Agricultural Sciences, BHU, Varanasi. The studies revealed that the pest activity commenced from 31st Standard meteorological week (SMW) and continued to 49th SMW. The leaf folder reaches a peak level at 49th standard week with 17.6 larva/10 hills. The dead heart noticed to reaches the peak level of infestation during the 42nd standard week with 6.23 per cent of dead. The rice white ear reaches the peak level of infestation during 49thstandard week with 10.93%. The rice brown plant hopper reaches the peak level during the 41st standard week with 19.33 insects per 10 hills. The correlation of yellow stem borer for dead heart shows significant positive correlation with the relative humidity and non-significant negative correlation with highest temperature, significant negative correlation with minimum temperature, average temperature, rainfall. The correlation of% white ears shows non-significant negative correlation with rainfall, significant negative correlation for maximum temperature, minimum temperature, average temperature, and relative humidity. The correlation of rice leaf folder shows non-significant negative correlation with rainfall, significant positive correlation with relative humidity, non-significant positive correlation for highest temperature, lowest temperature and temperature average. The correlation of rice brown plant hopper shows non-significant negative correlation with rainfall, highest temperature, lowest temperature and temperature average.