Mealy bug causes increasing threat to grape cultivation which leads to considerable yield loss.
Life cycle and appearance
Mealy bugs are found in crevices of stem, on leaves and berries. Mealy bugs are pinkish and covered with white mealy wax. Female lays 300-500 eggs in loose cottony ovisac and eggs are orange in colour. First instar nymphs also called as crawlers are mobile, start sucking the plant sap and form colonies and are orange in colour. Female mealy bugs are abundantly found causing damage to the crop while males are very rare. Females reproduce partheno-genetically without mating with males. Mealy bug completes its life cycle in 30 days. Ants are get attracted to honey dew secreted by mealy bug and helps in spreading of mealy bugs.
Adults and nymphs suck the sap from the leaves, shoots, flowers and grape bunches. Malformation of leaves and shoot tips due to infestation of growing points. Honey dew secretion of mealy bugs support sooty mould growth on infected area. Young vines often die due to severe infestation of mealy bugs. Feeding damage in grapes is minimal but the marketability is greatly affected due to its cottony egg mass, honey dew, sooty mould and dead mealy bugs on grape berries. Infected bunches are not suitable for making raisins.