Plant growth is affected by a plethora of environmental factors including microorganisms. Trichoderma species are free-living fungi which are beneficial to plant by stimulating growth and disease resistance of plant, not only in the rhizosphere but also in the aerial parts. Here, we investigated the role of MAPK-mediated activation of plasma membrane (PM) H+-ATPase in regulating the leaf colonization of Trichoderma viride Tv-1511 and its growth-promoting effects in Arabidopsis. T. viride Tv-1511 colonized in the leaves of wild-type Arabidopsis leaves and induced the growth-enhanced phenotypes including increased biomass production, elevated nutrient uptake and stimulated leaf and seedling development. PM H+-ATPase plays an important role in the plant development and environmental responses. Results showed that PM H+-ATPase activity and expression of AHA1 gene was enhanced in T. viride Tv-1511-inoculated Arabidopsis. AHA1-deficiency inhibited the colonization of T. viride Tv-1511 in Arabidopsis leaves, and mutants in AHA1 gene were found to reduce the growth-promoting and developmental effects of T. viride Tv-1511 inoculation. Furthermore, MAP kinase 6 (MPK6) was determined to be activated by T. viride Tv-1511 inoculation, and involved in the leaf colonization and growth promotion induced by T. viride Tv-1511 by regulating the elevated expression and activity of PM H+-ATPase in Arabidopsis inoculated by T. viride Tv-1511. Taken all, our results highlighted the important role of MPK6-mediated increase of PM H+-ATPase expression and activity in the regulation of leaf colonization and plant growth promotion of T. viride Tv-1511.

中文翻译：

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Trichoderma viride Tv-1511 通过调节 MAP 激酶 6 介导的质膜 H+-ATPase 活化来定植拟南芥叶片并促进拟南芥生长

植物生长受到多种环境因素的影响，包括微生物。木霉属物种是自由生活的真菌，通过刺激植物的生长和抗病性对植物有益，不仅在根际而且在地上部分。在这里，我们研究了 MAPK 介导的质膜 (PM) H+-ATPase 激活在调节绿色木霉 Tv-1511 的叶片定植中的作用及其在拟南芥中的生长促进作用。T. viride Tv-1511 在野生型拟南芥叶片中定植，并诱导生长增强表型，包括增加生物量产量、增加养分吸收以及刺激叶片和幼苗发育。PM H+-ATPase 在植物发育和环境响应中起重要作用。结果表明，在T. viride Tv-1511 接种的拟南芥中，PM H+-ATPase 活性和AHA1 基因表达增强。AHA1 缺陷抑制拟南芥叶片中 T. viride Tv-1511 的定植，并且发现 AHA1 基因中的突变体降低了 T. viride Tv-1511 接种的生长促进和发育作用。此外，确定 MAP 激酶 6 (MPK6) 被 T. viride Tv-1511 接种激活，并通过调节 PM H+- 的升高表达和活性参与 T. viride Tv-1511 诱导的叶片定植和生长促进T. viride Tv-1511 接种的拟南芥中的 ATP 酶。总而言之，我们的结果强调了 MPK6 介导的 PM H+-ATPase 表达和活性增加在调节 T. viride Tv-1511 的叶片定植和植物生长促进中的重要作用。