番茄黄化曲叶病毒对烟粉虱MED隐种取食行为的影响

Probing and feeding behaviors of the MED cryptic species of Bemisia tabaci (Gennadius) effected by TYLCV

为探究番茄黄化曲叶病毒(TYLCV)对烟粉虱刺探取食行为的影响并研究其与烟粉虱之间的互作关系。利用EPG记录了感染TYLCV的MED隐种在番茄寄主上的取食波形,并与未感染TYLCV的MED隐种的取食波形进行了比较研究。结果表明,烟粉虱开始取食行为后,带毒MED和未带毒MED平均刺探次数和非刺吸时间占总取食时间的比例方面没有显著差异。带毒MED从口针刺探开始至到达韧皮部的平均时间为46min,从记录开始至口针第一次到达韧皮部的平均时间为135min,未带毒MED相对应的平均时间分别为19min和25min,两者结果差异显著;在烟粉虱取食番茄韧皮部阶段,带毒和未带毒MED的唾液分泌总时间分别为9min、3min,第一次韧皮部持续吸食平均时间分别为143min、26min,带毒MED显著高于未带毒MED。带毒MED在第一次持续吸食至第一次取食结束的平均时间为15min,显著高于未带毒MED的4min。综上所述,带毒MED完成整个刺探取食行为的平均时间较未带毒MED显著增加,特别是唾液的分泌时间以及第一次在韧皮部的持续吸食时间。表明,TYLCV能促进MED加强唾液分泌和韧皮部取食,从而促进病毒的传播。

Mediterranean （MED） cryptic species of Bemisia tabaci is one of most prevalent invasive insect in China. It was proved that MED is an important vector of Tomato Yellow Laf Curl Virus （TYLCV）. The probing and feeding behavior between TYLCV- infected and TYLCV- uninfected MED, has been studied with Electrical penetration graph （EPG）. In order to find out interaction between TYLCV and B. tabaci, the waves on feeding behavior from tomato leaves have been recorded and compared with each other. The results showed that there is no difference between TYLCV - infected and TYLCV- uninfected MED in probe numbers and percentage of non - probe time from the start of penetration to achieving phloem on tomato. All the time below is average time. The infected whitefly cost 46 rain from the beginning of pierce to leaf phloem, and 135 min to 1 s, reached phloem, both significantly more than uninfected whitefly （26 min, 20 min）. During the progress from salivation to first sustained feeding in phloem, the infected and uninfected MED take 9 m and 3 m on the total time of salivation, and 143 min and 26 min on the total time of 1^at sustained feeding in phloem. At the last period of feeding behavior, the time from 1 st sustained feeding in phloem to the end of feeding on the host plants are 15 min and 4 min between the infected whitefly and uninfected whitefly. It is concluded that the TYLCV - infected obviously used more time than TYLCV - uninfected MED to finish a whole process of the probing and feeding behaviors on tomato leaf in our studies, especially the time of salivary secretion and sustained feeding. It showed that TYLCV could strengthen salivary secretion and sustained feeding of MED, which consequently promoted virus transmission.