To assess the impact of weather parameters on mustard aphid, a field experiment was conducted during Rabi season 2011-12 to 2017-18 at Main Castor-Mustard Research Station, . Agricultural University, Sardarkrushinagar. The experiment was laid down in randomized block design consisting five varietal treatments viz. BSH-1, GSC-6, T-27, GS1 and GDM-4 with three replications. The crop was sown during 24th – 30th Sept as timely sown crop and 15th – 21st Oct as late sown crop. The results revealed that the maximum incidence of aphid was observed in late sown crop as compared to early sown crop. The correlation study between aphid population and weather parameters revealed that the maximum temperature (Tmax), minimum temperature (Tmin) and growing degree days (GDD) had significant negative correlation with aphid population. Morning relative humidity, evening relative humidity, sunshine hours and wind speed did not have significant correlation with aphid population. The regression models were developed with Tmax and GDD could explain 72 to 87 percent variation in aphid population in different cultivars. | Effect of weather parameters on population dynamics of mustard aphid
