Population buildup of mustard aphid, Lipaphis Erysimi (Kalt.) on Indian mustard in relation to same abiotic factors

To study the population buildup of mustard aphid, Lipaphis erysimi (Kalt.) on Indian mustard, the field experiments were conducted at Meerut, Uttar Pradesh, during 2010–11 and 2011–12. Studies revealed that the incidence of mustard aphid started in the 51st standard week i.e. 3rd week of December during both the years and reached to peak level in 5th standard week i.e. 1st week of February and 8th standard week i.e. 4th week of February, during 2010–11 and 201112, respectively. During the period of maximum activity period of mustard aphid the maximum temperature, minimum temperature and mean relative humidity ranged from 13.35 to 24.71OC, 3.41 to 9.58OC and 51.14 to 72.13 per cent, respectively. The studies reveled positive correlation with maximum temperature that is non significant during 2010–11 and significant during 201112, positive and non significant correlation existed with minimum temperature and a negative and non significant correlation was observed with mean relative humidity during both the years.