Effects of host plants on selection behavior and biological parameters of Bemisia tabaci Gennadius biotype B

Based on the observation of free diffusion in petri dish and biology,the selection behavior and biological parameters of Bemisia tabaci Gennadius biotype B on host plants cucumber,eggplant,pepper,cotton,and sweet potato were investigated.No difference was observed in the individual number of B.tabaci on the five host plant leaves during the early period of free diffusion(within 2 h),but changes were found within the following periods(4-48 h),i.e.,the B.tabaci individuals increased on cucumber,decreased on pepper,and were relatively stable on eggplant,cotton,and sweet potato,which indicated that there were significant differences in the selectivity of B.tabaci on the five host plants,with the highest selectivity to cucumber and the lowest selectivity to pepper.Pretreatment by starvation and imidacloprid did not affect the selectivity of B.tabaci.There were significant differences on the honeydew excretion of female B.tabaci adults on the host plants,which was in the order of cucumbersweet potatocottoneggplantpepper.The average longevity of B.tabaci adults on cucumber,eggplant,sweet potato,and cotton was significantly longer than that on pepper,and the total number of eggs laid per female on cucumber,eggplant,sweet potato,and cotton(224.33,182.33,191.73,and 172.60 respectively)was significantly larger than that on pepper(only 47.83).No significant differences were observed in the hatching rate and development period of the eggs on the five host plants.The development period of nymphs on cucumber,eggplant,sweet potato,and cotton was 10.60 d,11.96 d,11.11 d,and 13.20 d,and the mortality was 5.21%,27.78%,17.24%,and 37.11%,respectively.The nymphs failed to develop normally on pepper.