Скачать или смотреть Rakshk..... Whiteflies (Aleyrodidae) Control in brinjal (वांगे) !! 

Description and Life Cycle: Whiteflies are small insects (1 to 3 millimeter). Adults have four broad wings of approximately the same size. The adult is the most mobile stage and is responsible for colonizing the host plant. Whiteflies can move and disperse over long distances by flying upward and being picked up and carried by air currents. Eggs are usually laid on the underside of young leaves and may be deposited randomly throughout the leaf, in circles, arcs or spirals, depending on the species. The eggs hatch into mobile first instars called crawlers, which search and find a suitable feeding site. They then insert their mouthparts and remain in one place for the rest of their immature stages. Second to fourth instars are called nymphs and resemble small scale insects. Nymphs are oval and may be pale yellow to black, depending on the species. The late fourth instar is also known as “pupa” because mobile adults emerge from the exoskeleton of sessile nymphs after development is complete. Silverleaf whitefly fourth instars are also known as “red-eye nymphs” because the relatively large eyes of the developing adult are already visible through the nymph integument (skin) during this stage. The complete life cycle varies from about 21/2 to 5 weeks according to temperature conditions and species. Many overlapping generations can occur each year. Adults and nymphs feed by inserting their mouthparts into plant tissue and sucking phloem sap. Damage: Whiteflies can damage plants directly or indirectly. Direct damage is caused through their feeding, which removes plant sap and stunts plant growth, especially in young plants. Silverleaf whitefly feeding has been associated with several plant disorders, including silverleaf of squash, stem blanching and whitening of poinsettia and cruciferous vegetables, and irregular ripening of tomatoes. Indirect whitefly damage is caused by the large amounts of sticky honeydew secreted during feeding. Honeydew may cover plants and support the growth of sooty mold, which reduces the plant’s ability to use light for photosynthesis. In addition to direct and indirect damage, whiteflies may carry and transmit viral diseases that can severely damage susceptible plants.