State Key Laboratory of Hulless Barley and Yak Germplasm Resources and Genetic Improvement, Lhasa, 850002, China.
Research Institute of Agriculture, Tibet Academy of Agricultural and Animal Husbandry Sciences, Lhasa, 850002, China.
Sci Rep. 2018 Oct 8;8(1):14928. doi: 10.1038/s41598-018-33113-7.
Powdery mildew is a fungal disease that represents a ubiquitous threat to crop plants. Transcriptomic and metabolomic analyses were used to identify molecular and physiological changes in Tibetan hulless barley in response to powdery mildew. There were 3418 genes and 405 metabolites differentially expressed between the complete resistance cultivar G7 and the sensitive cultivar Z13. Weighted gene coexpression network analysis was carried out, and the differentially expressed genes were enriched in five and four major network modules in G7 and Z13, respectively. Further analyses showed that phytohormones, photosynthesis, phenylpropanoid biosynthesis, and flavonoid biosynthesis pathways were altered during Qingke-Blumeria graminis (DC.) f.sp. hordei (Bgh) interaction. Comparative analyses showed a correspondence between gene expression and metabolite profiles, and the activated defenses resulted in changes of metabolites involved in plant defense response, such as phytohormones, lipids, flavone and flavonoids, phenolamides, and phenylpropanoids. This study enabled the identification of Bgh responsive genes and provided new insights into the dynamic physiological changes that occur in Qingke during response to powdery mildew. These findings greatly improve our understanding of the mechanisms of induced defense response in Qingke and will provide new clues for the development of resistant Tibetan hulless barley varieties.
白粉病是一种真菌病，对作物构成普遍威胁。本研究采用转录组学和代谢组学分析方法，鉴定了青稞对白粉病的抗性反应中的分子和生理变化。在完全抗性品种 G7 和敏感品种 Z13 之间，有 3418 个基因和 405 个代谢物差异表达。进行了加权基因共表达网络分析，差异表达基因分别在 G7 和 Z13 中富集到五个和四个主要网络模块中。进一步分析表明，在青稞-禾本科布氏白粉菌（Bgh）互作过程中，植物激素、光合作用、苯丙烷生物合成和类黄酮生物合成途径发生了改变。比较分析表明，基因表达与代谢物谱之间存在对应关系，激活的防御反应导致与植物防御反应相关的代谢物发生变化，如植物激素、脂质、黄酮和类黄酮、酚酰胺和苯丙烷。本研究鉴定了 Bgh 响应基因，为青稞对白粉病反应中发生的动态生理变化提供了新的见解。这些发现极大地提高了我们对青稞诱导防御反应机制的理解，并为培育抗青稞品种提供了新的线索。
