The larvae and the adults consume the plant’s sap and cause chlorotic spots to appear on the leaf blade. These spots are later disfigured by honeydew and the sooty moulds that grow there. In heavy infections, the spots may coalesce and engulf the whole leaf, which eventually turns yellow, apart from the area around the veins. The leaves may later become deformed, curl or take a cupping shape. Silverleaf whiteflies transmit viruses such as tomato yellow leaf curl virus or cassava brown streak virus.
Silverleaf whiteflies measure about 0.8 mm and have the body and both pairs of wings covered with a white to yellowish powdery, waxy secretion. They are often found on the underside of the leaves, where females lay their eggs. Tiny, yellow to white larval scales later appear there and are visible to the naked eye. In severe infestations, numerous small and white adult whiteflies will emerge in a cloud when the plant is shaken. Between plantings, adults survive on alternative hosts plants.
Employ natural insecticides based on sugar-apple oil (Annona squamosa) for effective population control. Also introduce or stimulate natural antagonists such as the parasitoid wasp Eretmocerus eremicus, predatory mites or nematodes. Pathogenic fungi have also been used to control/eradicate the pest. A new group of environmentally-friendly insecticides with surfactant-like properties kill the pest by overcoming the protective waxes on larvae and adults.
Always consider an integrated approach with preventive measures together with biological treatments if available. Silverleaf whiteflies quickly develops resistance to all pesticides, so a rotation of different products is recommendable. If no alternative treatment is available, apply combinations of pesticides based on bifenthrin, buprofezin, fenoxycarb, deltamethrin, azadirachtin, pymetrozine or spiromesifen to control the insect.
Perform intercropping practices with non-hosts.,Check plants regularly for whiteflies, especially the young shots.,Remove leaves with eggs or larvae on them.