Studies On Resistance Of Different Tomato Varieties To Bemisia Tabaci (Gennadius) And Its Mechanism

Bemisia tabaci (Gennadius) was a serious pest of tomato, which could significantly decrease yield and nutritional quality of tomato, causing serious economic losses. The control of whitefly, Bemisia tabaci is currently dependent on chemical pesticide, the resistant tomato against Bemisia tabaci is rarely reported. To explore the selectivity mechanism of Bemisia tabaci to different tomato varieties,20varieties of tomatoes was studied, and depended on the results,5main varieties of tomato was selected to study the physiological and biochemical difference, which provides theoretical basis for the resistance mechanism in tomato varieties.The major results are as follows:1.20different varieties of tomato were choosen to study whitefly, whitefly adults selectivity in indoor and outdoor environment. The results show that both in the indoor or outdoor environment, there was a significant difference on whitefly adults’selectivity:more writefly adults was found on the Lvjian2, the number is137.33outdoor and76.00indoor, while less on the Jingpinshujiao, the number is11.33outdoor. Both in indoor and outdoor environment, the result is similar, but whitefly adults’selectivity to Suhong2003、 Jinlinghongyu、Shitoudafen has some differences in different environment.2. The Chlorophyll, Soluble protein, total phenol and total alkaloid content of different tomato varieties was studied, whitefly adults prefer to the tomato varieties whos Chlorophyll, Soluble protein content is high and total phenol and total alkaloid content is low. But the Suhong2003、Jinlinghongyu are different. According to the result and population life table of writefly on different tomato varieties, Jinlinghongyu and Jingpinshujiao were selected as resistance varieties, Lvjian2as Sensitive varietie, and Suhong2003、Shitoudafen as Medium resistance varieties for the further study.3. Olfactory response of on whitefly adults to five varieties of tomatoes was studied, the results show that the writefly adults prefer to the Lvjian2and Jinlinghongyu, and there was a negative tropism of whitefly adults to the Suhong2003, and for the Shitoudafen and Jingpinshujiao there is no obvious tropism. Then the volatile content of the five tomato varieties was identified, the results show that the volatiles in Lvjian2are quite abundant, the peak area of Jinlinghongyu is only52.1, but the ratio of cineole, β-phellandrene, Myrcene, β-pinen, which show attraction to whitefly is hight, so whitefly adults have positive tropism to Lvjian2and Jinlinghongyu. There is little volatile in Jingpinshujiao, the volatile content of Shitoudafen is high, but β-caryophyllenewas and α-pinene which show negative tropism to whitefly was found, so there is no obvious selectivity of writefly adults to the two varieties. The volatile content of Suhong2003is low, but α-pinene was found, so writefly adults show negative tropism to it.4. Fitness of whitefly to different tomato varieties was studied. The results show that whitefly preferred Lvjian2, and had least preference for Jingpinshujiao. After writefly infestation, physiological and biochemical study results of the5different tomato varieties show that there are changes in the Soluble sugar, Soluble protein, Proline, Superoxide dismutase (SOD) and Peroxidase (POD) of different tomato varieties. But no significant change in total phenol and total flavonoids was found after the tomato was harmed by whitefly.