番茄黄化曲叶病毒对温室白粉虱适合度的影响

Effects of tomato yellow leaf curl virus on the fitness of greenhouse whitefly

【目的】温室白粉虱Trialeurodes vaporariorum(Westwood)是为害北方地区花卉蔬菜的主要粉虱种类,烟粉虱Bemisia tabaci(Gennadius)则在近些年逐渐频繁的花卉贸易活动中扩散至黑龙江省部分地区并取代了白粉虱成为当地温室害虫的优势物种,番茄黄化曲叶病毒(Tomato yellow leaf curl virus,TYLCV)是烟粉虱传播的一种重要双生病毒,对作物的危害十分严重,然而该病毒对本地白粉虱的影响及对烟粉虱与白粉虱种间竞争关系的影响尚待研究。【方法】本研究观察记录感染番茄黄化曲叶病毒的番茄植株上温室白粉虱和烟粉虱的种群动态及番茄形态和部分生理指标的变化。【结果】结果表明:1)有烟粉虱滋生的番茄植株矮小,根系发达;2)有白粉虱滋生的番茄略微矮粗,影响较小;3)感染病毒的番茄矮粗或矮小,根部无明显变化;4)染毒带虫相对于带虫处理而言,在白粉虱试验中,番茄植株矮小,根系生物量也骤减;与此相反,在烟粉虱试验中,番茄的反应相对缓和;5)此外,不同酶类对植株染毒的响应不同:Ach E酶活高不利于植株,而GST酶活高则有利于植株。【结论】总体而言:烟粉虱单独作用很不利于苗期番茄,白粉虱对苗期番茄没有明显的直接影响;而感染病毒会缓解烟粉虱对番茄的强烈刺激,而加重白粉虱对番茄的作用,即染毒使带白粉虱的苗期番茄生长发育受到明显抑制。与番茄变化情况相对应的是,染毒番茄上烟粉虱产卵较少,但在发育前期(从卵到伪蛹)存活率较高;染毒番茄上白粉虱产卵较多,但在前期存活率较低。本研究可为高纬度地区粉虱综合防控提供参考。

[Objectives] The greenhouse whitefly is a major insect pest of multiple horticultural and vegetable crops in Northern China. The sweet potato whitefly species complex is another pest species that has recently spread into parts of Heilongjiang Province as a result of the flower trade and is rapidly replacing native species to become the new dominant species. The tomato yellow leaf curl virus （TYLCV） is a begomovirus transmitted by the sweet potato whitefly that can cause serious damage to plant crops. There has been little recent research on the effect of this virus on the greenhouse whitefly, or on competition between these two whitefly species. [Methods] We observed the population dynamics of both whitefly specieson infected and un-infected tomato plants and related these to host plant＇s morphological and physical indices. [Results] 1） Tomato plants infested by the sweet potato whitefly became short and thin with more root biomass; 2） Plants infested with the greenhouse whitefly became a little shorter but thicker; 3） Infected plants became shorter and thicker （or thinner）, without significant root variance; 4） Compared with infested plants, plants that were both infected with the virus and infested with the greenhouse whitefly became shorter and thinner with a sharp decrease in root biomass, whereas those infested with the sweet potato whitefly showed much reduced symptoms; 5） Different enzymes responded differently to plant infection; higher Ache activity injured plants but higher GST was beneficial. [Conclusion[ Infestation by the sweet potato whitefly injured tomato seedlings, but the greenhouse whitefly didn＇t directly affect tomato plants; virus infection reduces the plant response to sweet potato whitefly infestation, but enhances the response to infestation by the greenhouse whitefly, that is to say, the growth and development of infected plants infested by the greenhouse whitefly was significantly suppressed. The sweet potato whitefly laid less eggs with a higher hatching rate on infected tomato plants whereas the greenhouse whitefly laid relatively more eggs with a lower hatching rate. These results have implications for the integrated management of whitefly pests in high latitude areas.