转换寄主前后扶桑绵粉蚧取食行为的EPG分析

EPG analysis of feeding behavior of the solenopsis mealybug,Phenacoccus solenopsis(Hemiptera: Pseudococcidae) before and after host shift

【目的】分析扶桑绵粉蚧Phenacoccus solenopsis在发生寄主转移前后的取食行为,以据此评价其寄主适应性。【方法】利用刺吸电位(EPG)技术,量化扶桑绵粉蚧转换寄主植物前后的取食行为并进行对比分析。【结果】寄主转换后,扶桑绵粉蚧的取食行为受到显著的影响,需要耗费更多的时间到达韧皮部,总取食时间显著变短,取食效率降低。但寄主转换后,下一代成虫的取食效率提高,总刺探数、取食刺探数、总刺探时间以及到达韧皮部的效率与时间均与寄主转换前的扶桑绵粉蚧个体不存在显著差异。【结论】扶桑绵粉蚧的取食行为存在高度可塑性,这种特性利于扩大其寄主植物范围,有可能是促其成为重要农业入侵生物的原因之一。

[ Aim ] To study the feeding behavior of Phenacoccus solenopsis during host shift for evaluating its host adaptability. [ Methods] Feeding behavior of the solenopsis mealybug was quantitatively analyzed by electronic penetration graph （EPG） technique to evaluate its resource utilization efficiency when transferred to a novel host. [ Results ] During host shift, feeding behavior were significantly affected, including more time needed to reach phloem, less total feeding time, and lower ingestion efficiency. The next generation adults on the transferred host, however, showed increased ingestion efficiency, together with similar feeding behavior as their mothers before host shift, including the total number and time of probes, time of feeding and the efficiency to reach phloem. [ Conclusion ] High plasticity of feeding behavior is advantageous for P. solenopsis to adapt the transferred host and should be beneficial to expand its host range, which is supposed to be one reason that P. solenopsis would be an important agricultural invasive pest.