Abstract:

In order to find a new plant pesticide, the petroleum ether extract, ethyl acetate and ethanol extracts from aerial parts of Tithonia diversifolia were isolated. The stomach action, repellent action, contact action, fumigation action of different Tithonia diversifolia extracts were studied and compared with drosophila as test object. The results showed that: the ethyl acetate extracts had very strong stomach effect on drosophila in the 10 mg/mL concentration and the stomach rate could reached 93.33% at 72 h. In the 50 mg/mL concentration, the three extracts had very strong repellent effect, the ethyl acetate and ethanol extracts could reached 100%, the petroleum ether extract could reached 85%; The ethyl acetate and ethanol extracts had stronger fumigation effect than the petroleum ether extract and both of them can reached 100% at 120 min. The contact action on drosophila of three extracts were all lower. Therefore, the secondary metabolites of Tithonia diversifolia showed that it has some development potential.