Management of Whitefly: Bemisia tabaci

Whitefly adults are tiny (about 1 mm long) moth-like insects. They are white to slightly yellowish in colour and their bodies and both pairs of wings are covered with a powdery and waxy secretion. They suck cell sap from the lower surface of the leaves. The symptoms of whitefly infestation are yellowing of leaves, withered plant parts and reduced flowering and fruiting. Sticky substances appear on the leaf surface and sooty mold develops on leaves and fruits, giving the plant a sickly black appearance. In severe infestation, plants start wilting and if the plant is shaken, a cloud of tiny moth-like insects flies out but rapidly resettles.

Whitefly is a common insect pest in Nepal. It is polyphagous, meaning it has a wide host range. It is a serious insect pest of many vegetables particularly tomatoes, eggplants and cucumber. Both nymphs and adults causes damage on crops. Whiteflies also transmit the viruses that cause yellow mosaic and leaf curl disease. They affect the seedling, vegetative growth and flowering stages of the plant.