Abstract:
Trichoderma spp. is known for its ability to enhance plant growth and suppress disease, but the mechanisms for its interaction with host plants and pathogens remain unclear. This study investigated the transcriptomics and metabolomics of peanut plants (Arachis hypogaea L.) inoculated with Trichoderma harzianum QT20045, in the absence and presence of the stem rot pathogen Sclerotium rolfsii JN3011. Under the condition without pathogen stress, the peanut seedlings inoculated with QT20045 showed improved root length and plant weight, increased indole acetic acid (IAA) production, and reduced ethylene level, with more active 1-aminocyclopropane-1-carboxylate acid (ACC) synthase (ACS) and ACC oxidase (ACO), compared with the non-inoculated control. Under the pathogen stress, the biocontrol efficacy of QT20045 against S. rolfsii was 78.51%, with a similar effect on plant growth, and IAA and ethylene metabolisms to the condition with no biotic stress. Transcriptomic analysis of peanut root revealed that Trichoderma inoculation upregulated the expression of certain genes in the IAA family but downregulated the genes in the ACO family (AhACO1 and AhACO) and ACS family (AhACS3 and AhACS1) consistently in the absence and presence of pathogens. During pathogen stress, QT20045 inoculation leads to the downregulation of the genes in the pectinesterase family to keep the host plant\'s cell wall stable, along with upregulation of the AhSUMM2 gene to activate plant defense responses. In vitro antagonistic test confirmed that QT20045 suppressed S. rolfsii growth through mechanisms of mycelial entanglement, papillary protrusions, and decomposition. Our findings highlight that Trichoderma inoculation is a promising tool for sustainable agriculture, offering multiple benefits from pathogen control to enhanced plant growth and soil health.
摘要:
木霉属。以增强植物生长和抑制疾病的能力而闻名,但其与宿主植物和病原体相互作用的机制尚不清楚。这项研究调查了在不存在和存在茎腐病病原体的情况下,接种哈茨木霉QT20045的花生植物(ArachishypogaeaL.)的转录组学和代谢组学。在无病原体胁迫的条件下,接种QT20045的花生幼苗显示出改善的根长和植株重量,吲哚乙酸(IAA)产量增加,和降低乙烯水平,具有更有活性的1-氨基环丙烷-1-羧酸(ACC)合酶(ACS)和ACC氧化酶(ACO),与未接种的对照相比。在病原体的胁迫下,QT20045对S.rolfsii的生物防治效果为78.51%,对植物生长有类似的影响,和IAA和乙烯代谢到没有生物应激的条件。花生根的转录组学分析显示,在不存在和存在病原体的情况下,木霉属接种上调了IAA家族中某些基因的表达,但一致下调了ACO家族(AhACO1和AhACO)和ACS家族(AhACS3和AhACS1)中的基因。在病原体胁迫期间,QT20045接种导致果胶酯酶家族基因下调,保持寄主植物细胞壁稳定,与AhSUMM2基因的上调一起激活植物防御反应。体外拮抗试验证实QT20045通过菌丝缠结机制抑制罗氏球菌生长,乳头状突起,和分解。我们的发现强调木霉接种是可持续农业的一个有前途的工具,从病原体控制到增强植物生长和土壤健康提供多种好处。