Comparative Transcriptomics Suggests Early Modifications by Vintec® in Grapevine Trunk of Hormonal Signaling and Secondary Metabolism Biosynthesis in Response to Phaeomoniella chlamydospora and Phaeoacremonium minimum

Abstract

Given their well-known antifungal abilities, species of the genus <i>Trichoderma</i> are of significant interest in modern agriculture. Recent studies have shown that <i>Trichoderma</i> species can induce plant resistance against different phytopathogens. To further extend this line of investigation, we investigate herein the transcriptomic response of grapevine trunk to Vintec^®, which is a <i>Trichoderma atroviride</i> SC1-based commercial formulation for biological control of grapevine trunk diseases and which reduces wood colonization. The aim of the study is to understand whether the biocontrol agent Vintec^® modifies the trunk response to <i>Phaeoacremonium minimum</i> and <i>Phaeomoniella chlamydospora</i>, which are two esca-associated fungal pathogens. An analysis of transcriptional regulation identifies clusters of co-regulated genes whose transcriptomic reprogramming in response to infection depends on the absence or presence of Vintec^®. On one hand, the results show that Vintec^® differentially modulates the expression of putative genes involved in hormonal signaling, especially those involved in auxin signaling. On the other hand, most significant gene expression modifications occur among secondary-metabolism-related genes, especially regarding phenylpropanoid metabolism and stilbene biosynthesis. Taken together, these results suggest that the biocontrol agent Vintec^® induces wood responses that counteract disease development.