Abstract:  【Aim】 Oviposition is vital for the survival and development of insect populations. Our previous study demonstrated that Serangium japonicum prefer to lay eggs on eggplant (Solanum melongena) leaves. This study aims to explore the oviposition preference of S. japonicum to eggplant varieties with different leaf trichome densities, so as to further clarify the mechanisms regarding to leaf trichome-related oviposition preference in S. japonicum. 【Methods】 Leaf discs and plants of four eggplant varieties (Heidaodi, Heiniu, Riyouchangzhizhuang and Luoxing) were provided for S. japonicum to determine the oviposition preference. The offspring performance including the growth and development, and adult fecundity, predation capability and attachment force of S. japonicum on leaves of each of the four eggplant varieties was tested. Microstructure of the abaxial leaf surface of the four eggplant varieties, the preference of S. japonicum female adults to leaf odours, the length and width of Bemisia tabaci eggs on eggplant leaves, and the cannibalism risk of S. japonicum eggs by its female adults were examined. 【Results】 S. japonicum preferred to lay eggs on Heidaodi, where the shortest offspring developmental duration (15.41±0.21 d) and the highest fecundity (877.44±15.27 eggs laid per female) were found. However, the proportion of S. japonicum eggs had no significant correlation with offspring performance (developmental duration, survival rate and adult body weight) and adult performance (fecundity and predation capability), but was significantly positively correlated with the density and length of leaf trichomes on the abaxial leaf surface (ALS). Furthermore, the proportion of S. japonicum eggs laid on leaf discs was significantly positively correlated with the attachment force of its female adults. The attachment force of S. japonicum female adults was positively correlated with leaf trichome density but had no significant correlation with adult performance. The leaf odour, prey quality, and cannibalism risk on the four eggplant varieties had no significant effects on the oviposition preference of S. japonicum. 【Conclusion】 The density of ALS leaf trichome and the attachment force of S. japonicum mediated by leaf trichomes play an important role in the oviposition preference of S. japonicum.

Key words: Serangium japonicum, oviposition preference, leaf, leaf trichome density, preference-performance hypothesis, attachment force