Population Dynamics of Aphid [Lipaphis Erysimi (Kaltenbach)] on Mustard

Studies on the population dynamics of aphid, Lipaphis erysimi (Kaltenbach) on mustard revealed that the pest was active from November to February (flowering stage to harvest of the crop) and ranged between 0.43 and 4.67 aphid index/plant. The pest population exhibited highly significant negative correlation with maximum temperature and minimum temperature. Evening relative humidity and sunshine hours were also negatively correlated. whereas, morning relative humidity showed significant negative correlation. On the other hand, wind velocity exhibited highly significant positive correlation with the pest.