ĐẶC ĐIỂM HÌNH THÁI VÀ SINH HỌC CỦA BỌ PHẤN TRẮNG HẠI LÚA (ALEUROCYBOTUS INDICUS DAVID AND SUBRAMANIAN) TẠI ĐỒNG BẰNG SÔNG CỬU LONG

Whiteflies feeded on rice leaves collected in the Mekong River Delta (Long An, An Giang and Can Tho provinces) have scientific name Aleurocybotus indicus David and Subramaniam, belong to the order Hemiptera and family Aleyrodidae. The metamorphosis of whiteflies is different from that of other members of the suborder Homoptera as the last instar is quiescent and is called a pseudopupa. The results in laboratory showed that life cycle of whitefly is about 21.93 days. Adults of whiteflies are minute insects measuring 0.83 - 0.98 mm in length. The adults resemble tiny white moths with their wings covered by a white waxy powder. Adults are active and readily fly from leaves of rice when disturbed. Eggs are laid on the undersides of leaves or near the base of leaves in group 2 - 10 eggs or scattered. The larvae are also minute insects measuring 0.27 - 1.00 mm in length. Each female could lay about 96.9 eggs, especially to 240 eggs. Rate of eggs hatched and survive are very high (87.5%). Rate of changing from larvae to pupae and from pupae to adults are also high (81.6 and 97.5%, respectively). Thus, the growth rate of whitefly from egg to adult is 70.1%. It showed that each female could lay 68 whiteflies in next generation.