Abstract:To investigate the mechanism of wing dimorphism of rice white-backed planthopper (WBPH), Sogatella furcifera Horvth, experiments were carried out with pure-bred strains of both macropterous and brachypterous S.furcifera and compared the differentiation of wing dimorphism under gradient temperature, photoperiod, nymphal density, host plants, rice growth stages and nutrition of host plant, etc. The results showed that short-day was beneficial to brachypterous male S.furcifera; when nymphal density was ≥15 nymph/tube (3cm×20cm), brachypterous differentiation rate was lower than 16.9%. Host plant nutrition dominated the way of wing dimorphism, and there was a positive correlation between the total-protein of host plant and the differentiation ratio of brachypterous S.furcifera. Jointing time of rice was the most beneficial to the incidence of brachypterous S.furcifera, the differentiation rate was 45.2%; while the filling time was suitable for the occurrence of macropterous S.furcifera. The relationship between the wing dimorphism of F1 generation and parent biotypes was close, when parents were both brachypterous S.furcifera, the differentiation rate was 47.7％ in F1 generation. Whenever, the ratio of macropterous was always higher than that of brachypterous, and especially the number of brachypterous male was extremely low. Wing dimorphism of S.furcifera was not only dominated by genes but influenced by environmental factors as well.