| Sweetpotato whitefly, Bemisia tabaci Gennadius, also known as the cotton whitefly, is an important invasive pest of cropping systems worldwide, and has been identified one of the most harmful pest in fourteen invasive species by the International Union for Conservation of Nature (ICUN). With recent outbreaks, control of B. tabaci in crop fields mainly relies on the pesticide, but whiteflies appear to be resistant to many of the pesticides employed in their control, so biological control is becoming increasingly important. Mi-1 gene is an important resistance gene in tomato. The Mi-1 gene was intogressed from Lycopersicon peruvianum to L. esculentum. The tomato Mi-1 gene confers resistance to three species of root-knot nematode, potato aphid and sweetpotato whitefly, and it has broad application prospects. In the present study, two biotype of B. tabaci and tomato species with Mi-1 were used to evaluate the effect of tomato with Mi-1 on controlling the B. tabaci, to provide a scientific basis on use the Mi-1 gene in agricultural production. The results and conclusion were as follows,1. The development time of two biotypes B. tabaci were significant delayed after fed on tomato with Mi-lcompared with B.tabaci fed on tomato without Mi-1,3.5～4 days and 4.5～y4.8 days were delayed each. There are no difference of development time of B. tabaci in different genenrations after fed on tomato with Mi-1 in each biotype (PB-biotype=0.7762, PQ-biotype=0.9507). The development time of Q-biotype were delayed 0.3-1.3 days compared with B-biotype after fed on tomato with Mi-1 in same genenration, and the development time of Q-biotype were significant delayed after fed on tomato with Mi-1 compared with B-biotype in 15th generation((P=0.0450)). So tomato with Mi-1 could delay the development time of B. tabaci larval steadily and long-term. And the effect on Q-biotype B. tabaci is better than B-biotype B. tabaci after fed on tomato with Mi-1.2. The survival rate of two biotype B. tabaci larval is decreased after fed on tomato with Mi-1 compared with B.tabaci fed on tomato without Mi-1,10.1～14.3% and 17.6～22.7% were decreased in each biotype in different generations. After fed on tomato with Mi-1 in multi-generation, the survival rate of egg to adult of two biotypes B. tabaci is not significant difference in different generations (PB-biotype=0.3071, PQ-biotype=0.2042), and the survival rate of two biotype B.tabaci larval still lower after fifteen generation, Mi-1 is an useful gene for control the B. tabaci. And the survival rate of Q-biotype B.tabaci fed on is significant lower than B-biotype B. tabaci fed on tomato with Mi-1 in same generation,5.7%～9.2% were decreased after fed on tomato with Mi-1 in same generation, so the effect of Mi-1 gene on controlling the Q-biotype B. tabaci is better than B-biotype B. tabaci.3. Compared with B. tabaci fed on tomato without Mi-1, there is no significant difference of longevity of two biotype B. tabaci after fed on tomato with Mi-1, but the fecundity of female adult fed on tomato with Mi-1 is significant lower than the female adult fed on tomato without Mi-1, the number of egg laid on leaf of tomato with Mi-1 by two biotypes B.tabaci is decreased about 35%. After feeding on tomato Mi-1, the energy of B. tabaci must be "trade-off", the more energy for survival, while reducing the energy used for laying eggs, resulting in two biotypes of B. tabaci fertility decline.In this study, it is showed that the ability of B. tabaci is hard to adapt the resistance of tomato induced by Mi-1. Two biotypes of B.tabaci fed on tomato with Mi-1 would delay the development time, reduce the survival rate and decrease the fecundity, especially the Q-biotype. So the Mi-1 gene is the useful gene for controlling the B. tabaci and a wide prospect for using in agricultural production for control the B. tabaci.
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