Effect of weather parameters on seasonal incidence of yellow stem borer [Scirpophaga incertulas (Walker)] on paddy

The present investigation was conducted to study the effect of weather parameters on incidence of yellow stem borer [(Scirpophaga incertulas Walker)] in paddy, during the Kharif season of 2024–25 at the Central Research Farm, Department of Entomology, Sam Higginbottom University of Agriculture, Technology and Sciences, Prayagraj, Uttar Pradesh. While study of incidence it was revealed that the initial infestation of dead hearts commenced in the 35th standard meteorological week (SMW) with an average 4.33% incidence, peaking at 27.33% in the 40th SMW under conditions of high temperature, humidity, low rainfall, and moderate sunshine. A positive but non-significant correlation was observed between dead hearts infestation and all meteorological parameters except sunshine, which showed a negative nonsignificant correlation. White earhead symptoms first appeared in the 39th SMW with an average 9.42% incidence and peaked at 28.44% in the 43rd SMW. White earhead infestation exhibited a highly negative significant correlation with minimum temperature and rainfall, while maximum humidity and sunshine showed significant positive correlations. Minimum humidity had a negative significant impact, indicating that environmental conditions played a crucial role in influencing the infestation dynamics of yellow stem borer in paddy.