Characterisation of Chemical Signalling from Beneficial Trichoderma spp.

木霉菌是一种广泛存在于农业中的土壤腐生菌，具有生物防治活性。一些菌株还具有激活对多种病原体的诱导系统抗性(ISR)的能力。其他菌株已经被证明通过产生植物生长促进(PGP)化合物来刺激植物生长，尽管这两个特征很少同时被发现。该项目的重点是一种新的、自由生活的哈马特霉菌株，它在单子叶和双子叶植物中都表现出生防和促进植物生长(PGP)的能力，控制由出苗前和出苗后的病原菌引起的植物病害，可以诱导系统抗性和改变根构型，即使在冠层发育没有明显增加的物种(如玉米和小麦)中也是如此。与其他生物防治/PGP解决方案一样，现场应用面临许多挑战。复杂的串扰发生在有益的根际相互作用过程中，并受到气候、土壤类型、一年中的时间和寄主基因型的影响，例如在番茄-T。阿托维利和哈茨木霉的相互作用。因此，寻求了解和开发支持木霉在根际赋予有益特征的化学生态的研究具有重要的附加值。这个项目将使用跨学科的方法来阐明由钩端螺旋藻产生的新的生物活性化学物质，它有助于这些重要的农学特性。生物测定引导的分离(使用先进的色谱/光谱分析，即MS和核磁共振)将用于从保护生菜(Lactuca Sativa)或甘蓝(Brassicas)免受土壤病原菌核盘菌(Ssterotinia ssterotorum，SS)侵染的哈马特木霉(Trichoderma Hamatum)微宇宙提取物中鉴定生物活性天然产物。在土壤中捕获来自木霉分离物和寄主植物的已鉴定的化学信号将通过在存在或不存在SS的情况下将反相涂层纤维插入到木霉改良的植物土壤环境中进行，然后对捕获的化合物进行洗脱/分析。这项技术将阐明参与潜在增强对食草动物根部防御的因果代谢物的身份。三叶草根象甲Sitona Lepdus.这一跨学科项目将提供天然产物化学、化学生态学和微生物学方面的培训。该中心将设在Rothamsted的甲基溴实验室，在那里将提供生物化学方法方面的培训，包括生物测定指导的分馏和分析。第一年的轮换将在MG位于埃克塞特的实验室进行。应聘者将接受培训，以生成微观世界，从野生型和突变型钩端螺旋体中制备具有抗生素活性的提取物，并进行生物测试，以评估SS(或其他病原体)在提取物、组分和化合物背景下的表现。

Trichoderma species are ubiquitous soil saprotrophs utilized in agriculture for their biocontrol activities. Some strains additionally possess the ability to activate induced systemic resistance (ISR) to a broad range of pathogens. Other strains have been shown to stimulate plant growth through the production of plant-growth-promoting (PGP) compounds, although both traits are rarely found together. This project focuses upon a novel, free-living, strain of T. hamatum, which exhibits biocontrol and plant growth promotion (PGP) capabilities in both monocots and dicots, controls plant diseases caused by pre- and post-emergence pathogens, can induce systemic resistance and modify root architecture, even in species where no increase in canopy development is evident (e.g. maize & wheat). As with other biocontrol/PGP solutions, field application presents many challenges. Complex cross-talk occurs during beneficial rhizosphere interactions and is influenced by the climate, soil type, time of year and host genotype, e.g. in tomato-T. atroviride and T. harzianum interactions. Therefore, there is significant added value in studies that seek to understand and exploit the chemical ecology that underpins beneficial traits conferred by Trichoderma in the rhizosphere. This project will use an interdisciplinary approach to elucidate the novel bioactive chemistry produced by T. hamatum that contributes to these agronomically important traits. Bioassay-guided fractionation (using advanced chromatographic/spectroscopic analysis i.e. MS and NMR) will be used to identify bioactive natural products from microcosm extracts of Trichoderma hamatum that provide protection of lettuce (Lactuca sativa) or brassicas against the soil pathogen Sclerotinia sclerotorium (Ss). In-soil capture of the identified chemical signals, from Trichoderma isolates and the host plants will be carried out by the insertion of reverse-phase coated fibres into Trichoderma-amended soil environment of plants, in the presence or absence of Ss, and then elution/analysis of the captured compounds. This technique will shed light on the identity of the causal metabolites involved in potential enhancement of root defence against herbivores eg. clover root weevils, Sitona lepidus. This interdisciplinary project will provide training in aspects of natural product chemistry, chemical ecology and microbiology. It will be based in Rothamsted in the lab of MB, where training in biological chemistry methods including bioassay-guided fractionation and analysis will be provided. The first year rotation will be based in MG's lab in Exeter. The candidate will train in generating microcosms, preparation of extracts with antibiotic activity from wild-type and mutant T. hamatum and undertake biological assays to evaluate Ss (or other pathogen) performance in a background of extracts, fractions and compounds.