B型烟粉虱和温室白粉虱分别为害烟草后对烟草生长特性的影响

Different Effects on Growth Characteristics of Tobacco Plants Infested by Bemisia tabaci Biotype B and Trialeurodes vaporariorum

为比较B型烟粉虱和温室白粉虱分别取食烟草后对烟草生长特性的影响,明确2种粉虱取食诱导的烟草防御反应的差异和时间效应,探讨B型烟粉虱诱导的烟草防御反应在竞争取代温室白粉虱中的作用,采用直尺测量和烘箱烘干称重的方法,研究比较B型烟粉虱和温室白粉虱分别取食烟草不同时间后对烟草自身生长指标影响的差异。结果表明:在诱导寄主防御的虫口密度下,B型烟粉虱和温室白粉虱分别取食烟草不同时间后对烟草自身生长的影响存在显著差异,且具有时间效应。与对照烟草相比,B型烟粉虱取食烟草5天后对烟草生长没有明显的不利影响,但从取食10天开始出现显著不利影响,随着取食时间的延长对烟草的不利影响逐渐增加。烟粉虱取食15、20天后烟草株高分别降低了6.9、8.5 cm,平均节间距分别缩短了0.6、0.53 cm,叶片数量分别减少了2.1、2.6叶/株,系统叶叶面积明显增大,叶片变薄,单位面积干重分别降低了0.99、1.01 mg/cm2。温室白粉虱取食烟草不同时间后对烟草生长没有明显的不利影响。与温室白粉虱为害烟草后相比,B型烟粉虱为害烟草后产生了对烟草的特异性抑制反应,这可能与B型烟粉虱诱导烟草表达的特异性防御反应对自身资源的消耗有关。

The paper aims to compare the effects on growth characteristics of tobacco infested by Bemisia tabaci Biotype B and Trialeurodes vaporariorum, to determine the different defense responses of tobacco plantsand the temporal effect induced by the two kinds of whitefly, and to explore the interspecific competitionbetween B. tabaci and T. vaporariorum and the possible mechanism. The different effects on growthcharacteristics of tobacco after feeding different times by B. tabaci and T. vaporariorum were obtained throughusing ruler measurement and oven drying and weighing method. The results showed that there were significantdifferences of tobacco growth and temporal effect after feeding by B. tabaci and T. vaporariorum, respectively,under the whitefly population density reached plant induced defense. Compared with the control, tobaccofeeding by B. tabaci had no negative effect on plant growth for 5 d, but there was negative effect on plant growthfrom 10 d after feeding by B. tabaci, and the adverse effect gradually increased with the extension of B. tabaci feeding time. After previous feeding by B. tabaci for 15 d and 20 d, the tobacco plant height was decreased by6.9 and 8.5 cm, the average internode was shortened by 0.6 and 0.53 cm, the leaf number of tobacco plant wasdecreased by 2.1 and 2.6 leaf/plant, and the dry weight of per unit area was decreased by 0.99 mg/cm^2 and 1.01mg/cm^2, respectively. The tobacco feeding different times by T. vaporariorum had no negative effects.Compared with T. vaporariorum, B. tabaci can induce specific inhibition responses, B. tabaci-elicited declinesin growth may result from the re-allocation of resources from growth to defense.