| The hidden feeding habits of Bactrocera dorsalis in larval stage reduce the efficiency of chemical control, which is exacerbated by the widespread insecticide resistance. In order to develop more fertile repellent plant sources, four rounds of experiments were conducted on 23 non-host plant essential oils selectedas candidate materials. First, eight non-host essential oils with high repellent rate and significant difference between selection response rate and repellent response rate (P<0.01) were selected by behavioral tactic response experiment, which included Melaleuca viridiflora, Litsea cubeba, Pogostemon cablin, Angelica sinensis, Melaleuca alternifolia, Foeniculum vulgare, Mentha canadensis, Artemisia argyi. Then, through the oviposition repellent activity experiment, four plant essential oils with high repellent rate and extremely significant difference (P<0.01) between the treatment group and the control group were further screened. Then through the concentration gradient experiment, the repellent rate of M.viridiflora, P.cablin, A. sinensiswas the highest when the concentration was 5 000 μg/mL. When the concentration was 3 000 μg/mL, the repellent rate of M. alternifolia essential oil was the highest. Finally, the oviposition repellent effect of B. dorsalis was analyzed at the optimal concentration. The results showed that the oviposition holes and oviposition amount of B. dorsaliswere increased gradually, the repellent rate was decreased gradually, and the repellent oviposition activity of B. dorsalis was disappeared gradually with the propioning time of the fruits treated with the four essential oils at the optimal concentration. The rate of decline was faster in the first 3 days and then slowed down gradually. On the whole, M. viridiflora essential oil shows better performance in all aspects, and have higher oviposition repellent activity against B. dorsalis. It is expected to be developed into plant repellent agents in the future through the improvement measures. |
