Key Laboratory of Horticultural Plant Biology, Ministry of Education, Huazhong Agricultural University, Wuhan, 430070, China.
Key Laboratory of Fruit Breeding Technology of Ministry of Agriculture, Zhengzhou Fruit Research Institute, Chinese Academy of Agricultural Sciences, Zhengzhou, 450009, China.
BMC Genomics. 2018 Nov 28;19(1):846. doi: 10.1186/s12864-018-5215-7.
The green peach aphid (GPA), Myzus persicae (Sülzer), is a widespread phloem-feeding insect that significantly influences the yield and visual quality of peach [Prunus persica (L.) Batsch]. Single dominant gene (Rm3)-based resistance provides effective management of this invasive pest, although little is known about the molecular responses of plants to GPA feeding.
To illustrate the molecular mechanisms of monogenic resistance in peach to young tissue-infecting GPAs, aphid-resistant/aphid-susceptible peach lines from a segregating population with Rm3/rm3 and rm3/rm3 genotypes were infested with GPAs for 3 to 72 h. Transcriptome analysis of the infested tissues identified 3854 differentially expressed genes (DEGs). Although the majority of the DEGs in the resistant line also responded to aphid attack in the susceptible line, the overall magnitude of change was greater in the resistant line than in the susceptible line. The enriched gene ontology of the 3854 DEGs involved in plant defence responses included redox situation, calcium-mediated signalling, transcription factor (e.g., WRKY, MYB, and ERF), MAPK signalling cascade, phytohormone signalling, pathogenesis-related protein, and secondary metabolite terms. Of the 53 genes annotated in a 460 kb interval of the rm3 locus, seven genes were differentially expressed between the aphid-resistant and aphid-susceptible peach lines following aphid infestation.
Together, these results suggest that the Rm3-dependent resistance relies mainly on the inducible expression of defence-related pathways and signalling elements within hours after the initiation of aphid feeding and that the production of specific secondary metabolites from phenylpropanoid/flavonoid pathways can have major effects on peach-aphid interactions.
绿桃蚜（GPA），桃蚜（Sülzer），是一种广泛的韧皮部取食昆虫，它显著影响桃的产量和视觉品质[Prunus persica（L.）Batsch]。基于单一显性基因（Rm3）的抗性为这种入侵害虫提供了有效的管理，尽管对植物对 GPA 取食的分子反应知之甚少。
为了说明桃对年轻组织侵染 GPA 的单基因抗性的分子机制，用具有 Rm3/rm3 和 rm3/rm3 基因型的分离群体中的抗蚜/感蚜桃系进行了 3 至 72 小时的 GPA 侵染。侵染组织的转录组分析鉴定了 3854 个差异表达基因（DEGs）。尽管抗性系中大多数 DEGs 也对感蚜系中的蚜虫攻击有反应，但抗性系中的整体变化幅度大于感蚜系。3854 个 DEGs 的富集基因本体论涉及植物防御反应，包括氧化还原状态、钙介导的信号转导、转录因子（如 WRKY、MYB 和 ERF）、MAPK 信号级联、植物激素信号转导、病程相关蛋白和次生代谢物。在 rm3 基因座的 460kb 间隔区内注释的 53 个基因中，有 7 个基因在蚜虫侵染后在抗蚜和感蚜桃系之间差异表达。
综上所述，这些结果表明，Rm3 依赖性抗性主要依赖于蚜虫取食开始后数小时内防御相关途径和信号元件的诱导表达，而苯丙烷/类黄酮途径中特定次生代谢物的产生可能对桃蚜相互作用产生重大影响。
