Effect of potato planting dates on the population build up of Myzus persicae (Sulzer)

Aphid population on potato planted at monthly intervals on four dates, starting from 15th October, remained below the critical level i.e. 20 aphid/100 leaves upto 60, 50, 40 and 20 days of crop age. The aphids number was found varying on all the four planting dates on the similar crop stage. The 15th October planted crop was found most suitable for growing seed potatoes than other dates. The relationship between population of M. persicae and crop age for the crop planted on 15th October was quadrate, the equation being Y=334.29−16−9974 + 0.1811 x² (R²=0.43).