Laboratorio Nacional de Innovación Ecotecnológica para la Sustentabilidad (LANIES), Instituto de Investigaciones en Ecosistemas y Sustentabilidad (IIES), UNAM, Mexico; IIES-UNAM, Antigua carretera a Pátzcuaro No. 8701, Col. Ex-Hacienda de San José de la Huerta, 58190 Morelia, Michoacán, Mexico.
Division of Terrestrial Ecosystem Research, Department of Microbiology and Ecosystem Science, Centre of Microbiology and Environmental Systems Science, University of Vienna, Vienna, Austria.
Microbiol Res. 2024 Apr;281:127621. doi: 10.1016/j.micres.2024.127621. Epub 2024 Jan 18.
Trichoderma spp. are free-living fungi present in virtually all terrestrial ecosystems. These soil fungi can stimulate plant growth and increase plant nutrient acquisition of macro- and micronutrients and water uptake. Generally, plant growth promotion by Trichoderma is a consequence of the activity of potent fungal signaling metabolites diffused in soil with hormone-like activity, including indolic compounds as indole-3-acetic acid (IAA) produced at concentrations ranging from 14 to 234 μg l, and volatile organic compounds such as sesquiterpene isoprenoids (C), 6-pentyl-2H-pyran-2-one (6-PP) and ethylene (ET) produced at levels from 10 to 120 ng over a period of six days, which in turn, might impact plant endogenous signaling mechanisms orchestrated by plant hormones. Plant growth stimulation occurs without the need of physical contact between both organisms and/or during root colonization. When associated with plants Trichoderma may cause significant biochemical changes in plant content of carbohydrates, amino acids, organic acids and lipids, as detected in Arabidopsis thaliana, maize (Zea mays), tomato (Lycopersicon esculentum) and barley (Hordeum vulgare), which may improve the plant health status during the complete life cycle. Trichoderma-induced plant beneficial effects such as mechanisms of defense and growth are likely to be inherited to the next generations. Depending on the environmental conditions perceived by the fungus during its interaction with plants, Trichoderma can reprogram and/or activate molecular mechanisms commonly modulated by IAA, ET and abscisic acid (ABA) to induce an adaptative physiological response to abiotic stress, including drought, salinity, or environmental pollution. This review, provides a state of the art overview focused on the canonical mechanisms of these beneficial fungi involved in plant growth promotion traits under different environmental scenarios and shows new insights on Trichoderma metabolites from different chemical classes that can modulate specific plant growth aspects. Also, we suggest new research directions on Trichoderma spp. and their secondary metabolites with biological activity on plant growth.
木霉属真菌是一种广泛存在于所有陆地生态系统中的自由生活真菌。这些土壤真菌可以刺激植物生长，增加植物对大量和微量营养素以及水分的吸收。通常，木霉对植物的生长促进是真菌信号代谢物在土壤中扩散的结果，这些代谢物具有激素样活性，包括吲哚类化合物，如吲哚-3-乙酸（IAA），其浓度范围为 14 至 234μg/L，以及挥发性有机化合物，如倍半萜类异戊二烯（C）、6-戊基-2H-吡喃-2-酮（6-PP）和乙烯（ET），在六天的时间内，其产生水平分别为 10 至 120ng，这反过来又可能影响植物激素调控的植物内源性信号机制。这种植物生长刺激不需要两种生物之间的物理接触，也不需要在根定植期间发生。当与植物相关联时，木霉可能会导致植物中碳水化合物、氨基酸、有机酸和脂质的含量发生显著的生化变化，如在拟南芥、玉米、番茄和大麦中检测到的那样，这可能会改善植物在整个生命周期中的健康状况。木霉诱导的植物有益效应，如防御和生长机制，可能会遗传给下一代。根据真菌在与植物相互作用过程中感知到的环境条件，木霉可以重新编程和/或激活通常由 IAA、ET 和脱落酸（ABA）调节的分子机制，以诱导对非生物胁迫（包括干旱、盐度或环境污染）的适应性生理反应。本文综述了这些有益真菌在不同环境条件下参与植物生长促进特性的典型机制，并展示了不同化学类别的木霉代谢物在调节特定植物生长方面的新见解。此外，我们还对木霉属及其具有生物活性的次生代谢物在植物生长方面的新研究方向提出了建议。
