ENTO 331 :: Lecture 19 :: Pests of Guava, Pomegranate and Sapota

Pests of Apple :: Major Pest :: Apple Woolly Aphid

1. Apple woolly aphid: Eriosoma lanigerum (Pemphigidae: Hemiptera) Distribution and status: Hilly tracts in India and world Host range: Apple Damage symptoms

Sap sucking by nymphs and adults results in weakening and death of the smaller plants; galls on the roots and white woolly patches on the trunk. Aphids suck cell sap from the bark of the twigs and from the roots underground. Swelling or knots appear on the roots which hinder the normal plant functions. Aphids crowd together covered with wooly white patches on the trunk. Bionomics

Reproduction is both sexual and asexual but mostly by parthenogenesis. Aphid is active throughout the year except in cold months of December and January. Wingless forms are present throughout the year whereas winged forms are seen from July to October. Alate form disperses by flight and gives rise to apterous forms by sexual reproduction. In winter, colonies on the tree trunks move to the base of the trunk just below the soil. Female produces 116 young ones, nymphal period 35-42 days with four instars. Management Use resistant root stock like Golden delicious, Morton stock 778, 779 or 793. Release eulophid parasitoid viz., Aphelinus mali during December and June to obtain maximum parasitization. Select healthy plants in the nursery and spray chlorpyriphos 20 EC 0.05% (2.5 ml per L of water) before planting in the main field. During leaf fall, spray diazinon 3.75 L 20 EC in 1500 -2000 L of water / ha against aerial forms. spray methyl demeton 25 EC or malathion 50 EC 2.0 L in 1500-2000 L of water per ha For controlling root forms during winter and summer respectively. Apply the fumigant paradichlorobenzene at 30-110 g/tree in a 15 cm deep trench around the tree about two meters away from the base of the affected tree.