Journal of Advances in Biology & Biotechnology

Mustard is an important rabi oilseed crop in India that is attacked by several major insect pests such as aphid, sawfly, cabbage butterfly, and painted bug, which cause significant yield losses. Their population dynamics are strongly influenced by weather factors like temperature and relative humidity, making it important to study their seasonal incidence for better pest management and forecasting. The present investigation was conducted at the Entomology Research Farm, Institute of Agriculture and Natural Sciences, Deen Dayal Upadhyay Gorakhpur University, Gorakhpur, Uttar Pradesh during the rabi season of 2022–23 to study the seasonal incidence of major insect pests of mustard in relation to weather variables. Mustard aphid, Lipaphis erysimi first appeared during the 48^th SMW and attained peak population (185.06 aphids/10 cm central shoot) during the 6^th SMW. Mustard sawfly, Athalia lugens proxima reached peak population of 8.29 larvae/plant during the 7^th SMW, while cabbage butterfly, Pieris brassicae and painted bug, Bagrada hilaris recorded maximum populations of 2.36 larvae/plant and 5.33 bugs/plant during the 6^th and 4^th SMW, respectively. Correlation analysis revealed that aphid population showed significant negative correlation with maximum (r = -0.599; p<0.05) and minimum temperature (r = -0.614; p<0.05), while painted bug also exhibited significant negative correlation with maximum (r = -0.768; p<0.01) and minimum temperature (r = -0.725; p<0.01). Evening relative humidity showed positive association with aphid (r = 0.558; p<0.05) and painted bug (r = 0.683; p<0.01) populations. The study indicated that weather parameters considerably influenced pest population dynamics in mustard crop.