番茄斑萎病毒侵染寄主植物有利于媒介昆虫西花蓟马的生理生化机制

The transmission of insect-vectored diseases entails extremely complex interplays among hosts, pathogens, and vectors, chemistry plays a key role in these interactions. Recently, we demonstrated the western flower thrips (WFT) Frankliniella occidentalis performed better on tomato spotted wilt virus (TSWV)-infected pepper plants than on healthy ones. As the performance of WFT is largely regulated by available nutrients and anti-herbivore defenses of the host plant, we hypothesize that the infection of TSWV significantly alters the key nutrient levels and ratios, as well as suppress anti-herbivore defenses in the host plant for WFT. In this study, the underlying physiological and biochemical mechanisms about the infection of TSWV benefit the reproduction and development of WFT on pepper plants will be investigated: 1) to explore the level of the carbohydrates and free amino acids in healthy and TSWV-infected pepper leaves; 2) to measure the level and gene expression profiles of JA and SA in healthy and TSWV-infected pepper leaves; 3) to determine the impact of exogenous JA or SA treatment of the healthy and TSWV-infected pepper on the biological characteristics of the WFT; 4) to investigate the impact of exogenous JA or SA treatment on the level and gene expression profiles of JA and SA in healthy and TSWV-infected pepper leaves. These results will provide a theoretical foundation for the efficient management of WFT and TSWV in the field.

媒介昆虫传播的病原体使寄主植物、病原体和媒介昆虫之间的互作变得极为复杂，化学物质在三者互作中起关键作用。最近，我们的研究发现西花蓟马在感染番茄斑萎病毒（TSWV）的辣椒上生物学表现更有优势。因为西花蓟马的生物学表现很大程度受寄主植物内营养物质水平和防御反应的调节。我们推测，TSWV感染辣椒显著改变了其体内的关键营养物质的水平和比例，也抑制了其体内的防御反应。本研究拟从寄主植物营养和防御的角度去探讨TSWV感染辣椒后有利于其传播媒介西花蓟马繁殖和发育的生理生化机制：1）测定健康和感染TSWV的辣椒叶片内游离氨基酸和碳水化合物的水平 2）测定健康和感染TSWV的辣椒叶片内JA和SA的水平及合成途径中相关基因的表达；3）测定外源JA或SA处理对取食健康和感染TSWV辣椒的西花蓟马生物学特性的影响；4）测定外源JA或SA处理对健康和感染TSWV的辣椒叶片内JA和SA水平及相关通路基因的表达的影响。

媒介昆虫传播的病原体使得寄主植物、病原体和媒介昆虫之间的互作变得极为复杂，化学物质在三者互作中起关键作用。我们前期研究发现西花蓟马在感染番茄斑萎病毒（TSWV）的辣椒上生物学表现更有优势。因为西花蓟马的生物学表现很大程度受寄主植物内营养物质水平和防御反应的调节。我们推测，TSWV感染辣椒显著改变了其体内的关键营养物质的水平和比例，也抑制了其体内的防御反应。本研究从寄主植物营养和防御的角度出发，探讨了TSWV感染辣椒后有利于其传播媒介西花蓟马繁殖和发育的生理生化机制：1）测定了健康和感染TSWV的辣椒叶片内游离氨基酸和碳水化合物的水平 2）测定了健康和感染TSWV的辣椒叶片内JA和SA的水平及合成途径中相关基因的表达；3）测定了外源JA或SA处理对取食健康和感染TSWV辣椒的西花蓟马生物学特性的影响；4）测定了外源JA或SA处理对健康和感染TSWV的辣椒叶片内JA和SA水平及相关通路基因的表达的影响。研究结果为田间TSWV和西花蓟马的有效防控提供了相应的理论依据。