Population dynamics of green apple aphid Aphis Pomi De Geer (Homoptera: aphididae) and Its Natural enemies in apple orchard of Kashmir

Abstract

Population dynamics of green apple aphid (Aphis pomi) in relation to the natural enemies and weather parameters was studied in three districts viz., Srinagar, Budgam, and Ganderbal of Kashmir during 2012–13 and 2013–14. The peak population of A. pomi was recorded as 39.5 and 37.0 aphids/shoot in Srinagar; 42.6 and 47.0 aphids/shoot in Budgam and 41.3 and 54.8 aphids/shoot in Ganderbal at 2nd fortnight of June during 2012–13 and 2013–14, respectively with exception during 2013–14 in Ganderbal the peak was attained at 1st fortnight of July. The natural enemies include coccinellids, syrphid fly and Chrysoperla and were recorded highest in 1st fortnight of July except Srinagar was on16th June during both years. Highest % of parasitization was found on 2nd fortnight of July and ranged 14.2 to 15.2% and 13.4–15.6% during 2012–13 and 2013–14, respectively. The A. pomi overwintering nymphs was 0.3 and 0.5/10 buds and their mean maximum population was 0.66 and 1.0/10 buds on 2nd fortnight of December during 2012–13 and 2013–14, respectively in Srinagar and trend was also similar in other locations of Kashmir. The temperature played major role to buildup the population of aphid, its predators and parasitoids and after attaining peak population of natural enemies, the aphid population tends to decrease. Relative humidity had a positive influence along with temperature on aphid population and rainfall had negative influence.