马铃薯应对马铃薯Y病毒与非介体昆虫胁迫的植物激素水平和基因表达变化

Changes in phytohormone levels and gene expression of potato plants in response to potato virus Y and a nonvector insect

马铃薯Y病毒(potato virus Y,PVY)及其非介体昆虫马铃薯块茎蛾(Phthorimaea operculella)是世界马铃薯产业的重要病虫害,为探究PVY是否影响马铃薯对马铃薯块茎蛾的生理响应,本研究分析了马铃薯块茎蛾在PVY侵染和健康对照植株上的生长表现,并对无病虫害、PVY侵染、模拟虫害处理(用马铃薯块茎蛾口腔分泌物涂抹),以及PVY侵染和模拟虫害协同处理的植株叶片进行了植物激素测定和比较转录组分析。结果显示:马铃薯感染PVY后对马铃薯块茎蛾的抗性显著提高;PVY侵染可抑制模拟虫害造成的脱落酸含量上升;与健康对照组相比,模拟虫害和PVY侵染处理分别诱导产生3998个和104个差异表达基因,而两者协同处理可诱导产生9178个差异表达基因,说明这2种胁迫共存对马铃薯产生了极大的生理影响。与模拟虫害处理相比,PVY侵染和模拟虫害协同处理诱导产生743个差异表达基因,而这些基因主要富集在转移酶活性、内质网中蛋白质加工、苯丙素生物合成等通路中,而脱落酸合成通路中众多基因表达下调,与该植物激素变化情况一致。综上所述,本研究系统分析了马铃薯应对PVY侵染、马铃薯块茎蛾模拟虫害以及两者协同处理的生理反应,为探究“植物-病毒-非介体昆虫”三者互作提供了科学依据。

Potato virus Y(PVY)and its nonvector insect of potato tuber moth(Phthorimaea operculella)are important disease and pest in global potato industry.In order to investigate whether PVY infection changed the physiological responses of potato plant to P.operculella,we studied performances of P.operculella on PVY-infected and non-infected healthy plants,and carried out the phytohormone analysis and comparative transcriptomic analysis for potato leaves which were affected by PVY infection and herbiory stimuli(dealing with the oral secretions of potato tuber moth),or co-stressed treatment.The results showed that the resistance to P.operculella was significantly increased in potato plants infected by PVY.Moreover,PVY infection also inhibited the increase of abscisic acid induced by herbivory stimuli.Compared with the healthy control plants,herbivory stimuli and PVY infection treatments produced 3998 and 104 differentially expressed genes(DEGs),respectively;while 9178 DEGs were induced by co-stressed treatment,suggesting that the co-stressed treatment may greatly affected the physiological responses in potato plants.Compared with the herbivory stimuli,the co-stressed plants had 743 DEGs,and many of them belong to the transferase activity,the protein processing in endoplasmic reticulum,and the phenylpropanoid biosynthesis pathways.And the expression levels of many genes in abscisic acid synthesis pathway were also down-regulated,which was consisted with the change of this phytohormone.In summary,this study systematically analyzed the physiological responses of potato plant confronted by the single-and co-stressed treatments of PVY infection and herbivory stimuli,which may provide scientific basis for exploring plant-virus-nonvector insect interactions.