Abstract:In order to understand host selective mechanism of Bemisia tabaci Gennadius biotype B, the insect feeding and oviposition behaviors on cotton (Gossypium hirsutum L.), cucumber (Cucumis sativus L.), cabbage (Brassica oleracea L.), tobacco (Nicotiana tobacum L.) and velvetleaf (Abutilon theophrasti Medic) were studied under controlled conditions using electrical penetration graph (EPG) technique and normal ecological methods, respectively. The results from EPG experiments indicated that the feeding graphs of the whitefly consisted of six waves (A, B, C, E, G and np) on all of the five host plants, but there were significant differences in the feeding percent ratio, frequency and average duration of E wave. While the insect fed on velvetleaf, its actual feeding percentage reached 83.8% with a feeding duration of 20.2min, which was significantly higher than that on other hosts. In general, the feeding adaptability of the B.tabaci adults on the plant species ranked as velvetleaf>cucumber>cotton>tobacco>cabbage. There was a positive relationship between fecundity of the adults and the duration they lived on the host plants, but the increasing rate of eggs was much lower in comparison with the first 24 hours. B.tabaci adults showed a stronger preference to oviposit on velvetleaf than that on cotton, but there were not significant differences among velvetleaf and cabbage, cucumber or tobacco. There was a positive relationship between fecundity of the adults and their density on the hosts in this experiment. However, the eggs on the plants of cabbage and velvetleaf at high adult densities were significantly higher than those on cucumber, cotton and tobacco.