Involvement of Trichoderma harzianum Epl-1 Protein in the Regulation of Botrytis Virulence- and Tomato Defense-Related Genes

Abstract

Several Trichoderma spp. are well known for their ability to: (i) act as important biocontrol agents against phytopathogenic fungi; (ii) function as biofertilizers; (iii) increase the tolerance of plants to biotic and abiotic stresses; and (iv) induce plant defense responses via the production and secretion of elicitor molecules. In this study, we analyzed the gene-regulation effects of Trichoderma harzianum Epl-1 protein during the interactions of mutant Δepl-1 or wild-type T. harzianum strains with: (a) the phytopathogen Botrytis cinerea and (b) with tomato plants, on short (24 h hydroponic cultures) and long periods (4-weeks old plants) after Trichoderma inoculation. Our results indicate that T. harzianum Epl-1 protein affects the in vitro expression of B. cinerea virulence genes, especially those involved in the botrydial biosynthesis (BcBOT genes), during the mycoparasitism interaction. The tomato defense-related genes were also affected, indicating that Epl-1 is involved in the elicitation of the salicylic acid pathway. Moreover, Epl-1 also regulates the priming effect in host tomato plants and contributes to enhance the interaction with the host tomato plant during the early stage of root colonization.

Deciphering Trichoderma–Plant–Pathogen Interactions for Better Development of Biocontrol Applications

“…T. harzianum Epl-1, a protein elicitor of the cerato-platanin protein family, elicited the expression of genes involved in the SA defense pathway in tomato plants in the presence or absence of the pathogen. This elicitor also downregulated the expression of virulence genes of Botrytis cinerea especially those involved in the biosynthesis of botrydial, an important phytotoxic sesquiterpene metabolite, suggesting a key role for this protein in T. harzianum biocontrol interactions [ 62 ].…”

Functional analysis of eliciting plant response protein Epl1-Tas from Trichoderma asperellum ACCC30536

“…harzianum ALL42 as a symbiotic fungus by beans 6 , but also the transcription of tomato defense-related genes during the T . harzianum- tomato interaction 13 , which indicated that Epl-1 could be important for plant protection in Trichoderma . Besides, EplT4 from T .…”

Nitric Oxide as a Beneficial Signaling Molecule in Trichoderma atroviride TRS25-Induced Systemic Defense Responses of Cucumber Plants Against Rhizoctonia solani

“…are the most common saprophytic fungi in the rhizosphere and they are very effective biological control agents (BCAs) impairing pathogens with different antagonistic strategies. Antibiosis, mycoparasitism, competition for niches and nutrients as well as induction of local and systemic defense responses in plants are suggested as the mechanisms by which Trichoderma controls infection process and disease development (Harman et al., 2004; Vinale et al., 2008; Elsharkawy et al., 2013; Gomes et al., 2017). Induction of plant defense mechanisms or “sensitization” of plants by prior application of Trichoderma is thought to be a promising plant protection strategy.…”

“…Induction of plant defense mechanisms or “sensitization” of plants by prior application of Trichoderma is thought to be a promising plant protection strategy. However, their beneficial influence on plants depends on the Trichoderma strain, plant species, pathogen, and soil-climate conditions (Harman et al., 2004; Singh et al., 2010; Hermosa et al., 2012; Yousef et al., 2013; Gomes et al., 2017).…”