Xu Wenjing, Xu Xiaoyi, Han Ran, Wang Xiaolu, Wang Kai, Qi Guang, Ma Pengtao, Komatsuda Takao, Liu Cheng
Crop Research Institute, Shandong Academy of Agricultural Sciences, Jinan, Shandong, China.
National Engineering Laboratory of Wheat and Maize, Jinan, Shandong, China.
Front Plant Sci. 2023 Feb 1;14:1125194. doi: 10.3389/fpls.2023.1125194. eCollection 2023.
Powdery mildew is a fungal disease devastating to wheat, causing significant quality and yield loss. Flavonoids are important secondary plant metabolites that confer resistance to biotic and abiotic stress. However, whether they play a role in powdery mildew resistance in wheat has yet to be explored. In the present study, we combined transcriptome and metabolome analyses to compare differentially expressed genes (DEGs) and differentially accumulated flavonoids identified in plants with and without powdery mildew inoculation. Transcriptome analysis identified 4,329 DEGs in susceptible wheat cv. Jimai229, and 8,493 in resistant cv. HHG46. The DEGs were functionally enriched using Gene Ontology and Kyoto Encyclopedia of Genes and Genomes, revealing the flavonoid synthesis pathway as the most significant in both cultivars. This was consistent with the upregulation of flavonoid synthesis pathway genes observed by quantitative PCR. Metabolome analysis indicated flavone and flavonol biosynthesis pathways as the most significantly enriched following powdery mildew inoculation. An accumulation of total flavonoids content was also found to be induced by powdery mildew infection. Exogenous flavonoids treatment of inoculated plants led to less severe infection, with fewer and smaller powdery mildew spots on the wheat leaves. This reduction is speculated to be regulated through malondialdehyde content and the activities of peroxidase and catalase. Our study provides a fundamental theory for further exploration of the potential of flavonoids as biological prevention and control agents against powdery mildew in wheat.
白粉病是一种对小麦具有毁灭性的真菌病害，会导致显著的品质和产量损失。黄酮类化合物是重要的植物次生代谢产物，赋予植物对生物和非生物胁迫的抗性。然而，它们是否在小麦对白粉病的抗性中发挥作用尚待探索。在本研究中，我们结合转录组和代谢组分析，比较了接种和未接种白粉病的植物中鉴定出的差异表达基因（DEG）和差异积累的黄酮类化合物。转录组分析在感病小麦品种济麦229中鉴定出4329个DEG，在抗病品种HHG46中鉴定出8493个DEG。利用基因本体论和京都基因与基因组百科全书对DEG进行功能富集，发现黄酮类化合物合成途径在两个品种中最为显著。这与通过定量PCR观察到的黄酮类化合物合成途径基因的上调一致。代谢组分析表明，接种白粉病后黄酮和黄酮醇生物合成途径的富集最为显著。还发现白粉病感染诱导了总黄酮含量的积累。对接种植物进行外源黄酮类化合物处理导致感染较轻，小麦叶片上的白粉病斑点更少、更小。据推测，这种减少是通过丙二醛含量以及过氧化物酶和过氧化氢酶的活性来调节的。我们的研究为进一步探索黄酮类化合物作为小麦白粉病生物防治剂的潜力提供了基础理论。
