Population dynamics of Myzus persicae (Sulzer) on potato crop under cropping systems prevalent in three different potato growing belts in India

Abstract

Population dynamics of peach aphid, Myzus persicae (Sulzer), on untreated/unsprayed potato crop was studied under cropping systems prevalent in three different potato growing regions, vb, north-western hills (Shimla), north-western plains (Jalandhar), and north-eastern plains (Patna). Observations consecutively recorded for three years revealed that M. persicae commenced appearing on potato crop in Shimla between the 3rd week of June and 1st week of July, and crossed the critical level of 20 aphids/100 compound leaves between 3rd week of July and 2nd week of August. Its population increased progressively till haulms cutting. At Jalandhar, M. persicae appeared on autumn crop (grown for seed) in the 4th week of November and crossed the critical level by the 4th week of December. Its maximum population was seen during the first fortnight of January at haulms cutting. On the other hand, it appeared soon after the emergence of spring planting, used for table potatoes in February and quickly crossed the critical level between 1st and 2nd week of February itself. An increasing trend in its population was evident till the 2nd week of March. Thereafter, it declined. Under agro-climatic conditions of Patna, M. persicae starts appearing in main winter (rabi) potato crop between the 3rd and 4th week of December. It crossed the critical level between 2nd and 4th week of January. Maximum population of aphids was seen between 2nd and 4th week of February. Thereafter it declined, probably, due to rise in atmospheric temperature and maturity of crop.