【作者】 史晓斌；

【导师】 张友军； 高希武；

【作者基本信息】 中国农业大学 ， 农业昆虫与害虫防治， 2014， 博士

【摘要】 烟粉虱是一种分布最广的世界性农业害虫。近年来,Q型烟粉虱入侵中国,在许多地域逐渐取代B型烟粉虱,并且在多数地区,烟粉虱爆发后随之产生了番茄黄化曲叶病毒病(TYLCV)的大爆发。本文以烟粉虱-植物-病毒互作关系为研究对象,通过比较B、Q型烟粉虱带病毒前后取食引起的植物防御反应的变化,以及增加植物防御反应对B、Q型烟粉虱产生的不同影响,寻找造成B、Q型烟粉虱与病毒互作差异的机制。测定了烟粉虱取食引起的植物内源茉莉酸(JA)和水杨酸(SA)含量及基因相对表达量,发现带毒Q型烟粉虱取食后JA含量显著低于不带毒Q型及带毒B型和不带毒B型烟粉虱取食,JA相关的上下游基因LOX和PIⅡ也表现出相同趋势。与JA不同,带毒B型取食后SA显著高于带毒Q型烟粉虱取食后的SA,然而不带毒B、Q型烟粉虱取食后无显著差异,带毒B型取食引起了较高的SA相关的基因相对表达量,而带毒Q型烟粉虱取食没有引起显著变化。测定了烟粉虱在带毒和不带毒时,其中一种烟粉虱取食后的植物对后取食的另外一种烟粉虱的产卵量、寿命及选择性的影响。结果发现,不带毒B型和Q型烟粉虱取食后的植物没有显著影响后来取食的另一种烟粉虱。带毒B型烟粉虱取食也没有影响带毒Q型烟粉虱,相反,带毒Q型取食后显著增加了带毒B、Q型烟粉虱的产卵量和寿命。且带毒Q型烟粉虱取食后叶片酶抑制剂活性显著低于其他三种烟粉虱取食后的酶抑制剂活性。外源SA对烟粉虱的生长发育有显著不利作用。在SA处理过的植物上,烟粉虱产卵量下降,寿命缩短,发育历期延长,卵存活率降低。与对照相比,在SA处理植物上烟粉虱的卵巢发育速度减慢,卵子数目减少,且带毒B型烟粉虱卵子数显著低于带毒Q型烟粉虱。外源SA处理增加了挥发物浓度,改变了挥发物成分,因此改变了烟粉虱的选择性。外源JA处理结果表明外源JA能降低烟粉虱的产卵量、寿命、发育历期和卵存活率,其中带毒Q型烟粉虱比其他三种烟粉虱表现出较好的生物学特性。外源JA处理增加了挥发物的浓度,改变了挥发物的成分,因此改变了烟粉虱的选择性。利用JA过表达的突变体研究了烟粉虱取食植物引起的不同反应。结果表明不带毒Q型烟粉虱取食降低了JA升高了SA,而带毒Q型烟粉虱取食更大程度抑制了JA却没有升高SA。不带毒Q型烟粉虱取食增加了挥发物的含量,然而,带毒Q型烟粉虱取食没有显著增加挥发物的含量,却改变了挥发物的成分。在突变体和对照植物上,带毒Q型烟粉虱的生物学特性都高于不带毒Q型烟粉虱,但是对两种植物的选择性却低于不带毒Q型烟粉虱。更多还原

【Abstract】 The whitefly, Bemisia tabaci (Hemiptera:Aleyrodidae), is one of the most widely distributed agricultural pests. In recent years, B, tabaci Q has invaded China, and Q has gradually displaced B in many areas now. In a number of regions of the world, invasion by B and/or Q has been followed by outbreaks of tomato yellow leaf curl virus (TYLCV).In this study, we investigated the interaction of whitefly-plant-virus. We compared the plant defense responses induced by B and Q Bemisia tabaci with virus or not, and determined the different effects of increased plant defense on whiteflies, to find the mechnism of the mutualistic relationship between TYLCV and Q Bemisia tabaci.We quantified the jasmonic acid (JA) and salicylic acid (SA) titers and relative gene expression of JA and SA in tomato leaves that were infested with viruliferous or non-viruliferous B and Q. Jasmonic acid content was significantly lower in leaves infested with viruliferous Q than in noninfested leaves or in leaves infested with nonviruliferous Q, viruliferous B, or nonviruliferous B. The expression of LOX and PI Ⅱ genes showed the same trend, i.e., the expression was much lower with viruliferous Q than with nonviruliferous Q, viruliferous B, or nonviruliferous B. SA titer was always higher in leaves that were infested with viruliferous B than with viruliferous Q, whereas the SA titer did not differ between leaves infested with non-viruliferous B and Q. The relative gene expression of SA signaling was increased by feeding of viruliferous B but was not increased by feeding of viruliferous Q.We examined the performance and effects of B. tabaci B and Q on plants previously attacked by nonviruliferous or viruliferous Q or B. Fecundity and longevity were similar for nonviruliferous whiteflies on plants previously attacked by nonviruliferous whiteflies. Fecundity and longevity were also similar for viruliferous Q on plants previously attacked by viruliferous B. In contrast, fecundity and longevity were greater for viruliferous B and Q on plants previously attacked by viruliferous Q. With regard to protease inhibitor (PI), PI activity was significantly lower in leaves infested with viruliferous Q than in noninfested leaves or in leaves infested with nonviruliferous Q, viruliferous B, or nonviruliferous B.The life history traits of B and Q were adversely affected on SA-treated plants. On SA-treated plants, both B and Q had lower fecundity, shorter longevity, longer developmental time and lower survival rate than on untreated plants. Compared with whiteflies feeding on control plants, those feeding on SA-treated plants had fewer oocytes and slower ovary development. On SA-treated plants, viruliferous B had fewer oocytes than viruliferous Q. Exogenous SA also increased the content and changed the composition of plant volatiles, resulting in altered choice behavior of whiteflies.The exogenous JA treatment showed reduced whitefly fecundity, longevity, developmental time, and survival rate. Viruliferous Q showed a higher performance than nonviruliferous Q, viruliferous B, or nonviruliferous B. Exogenous JA also increased the content and changed the composition of plant volatiles, resulting in altered choice behavior of whiteflies. The JA-overexpress plant was used to determine the difference defense response induced by non-viruliferous and viruliferous Q. The results showed that non-viruliferous Q reduced endogenous JA and induced endogenous SA However, viruliferous Q greatly reduced the endogenous JA while not induced endogenous SA compared with non-viruliferous Q. Infestion of non-viruliferous Q increased level of plant volatile substance. In contrast, infestion of viruliferous Q didn’t induce the content but changed the component of plant volatiles. Furthermore, on JA-overexpress plant and control plant, viruliferous Q B. tabaci showed a higher fecundity, longevity and survival rate but a lower preference than non-viruliferous Q B. tabaci.更多还原