Abstract: The relationships between ovarian development, body size and take-off behavior as well as the indicator significance of wax on the abdomen in the spiraling whiteflies (Aleurodicus dispersus) were studied by dissecting their ovaries and measuring their body size, in order to analyze the influence of the ovarian development and body size on take-off behavior. The results showed that the ovarian development of A. dispersus could be divided into 6 stages based on the morphological characteristics of ovaries and eggs, i.e., stage 0 (No oocyte stage), stage Ⅰ (Pre-vitellogenic stage), stage Ⅱ (Vitellogenesis stage), stage Ⅲ (Egg maturation stage), stage Ⅳ (Ovipositing stage), and stage Ⅴ (Post-oviposition stage). The ovaries of most take-off female adults were at stageⅣ (Ovipositing stage). The number of ovarioles of takeoff adults with wax was less than that of non-take-off adults, while the number of eggs was more than that of non-take-off adults, and the body size of take-off adults was different from that of non-take-off adults. The number of eggs and the body length of adults with wax were both correlative with their body size, but those of the other type of individuals were not. Most female adults with wax had mature spermatothecae. Therefore, the ovarian development had an effect on take-off activity, and the wax on the abdomen of A. dispersus was an important indicator of its body growth and reproductive maturity.

Key words: Aleurodicus dispersus, ovarian development, body size, wax, take-off behavior