AUTHOR=Poveda Jorge , Hermosa Rosa , Monte Enrique , Nicolás Carlos 

TITLE=The Trichoderma harzianum Kelch Protein ThKEL1 Plays a Key Role in Root Colonization and the Induction of Systemic Defense in Brassicaceae Plants

JOURNAL=Frontiers in Plant Science

VOLUME=10

YEAR=2019

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2019.01478

DOI=10.3389/fpls.2019.01478

ISSN=1664-462X

ABSTRACT=<p>The fungal genus <italic>Trichoderma</italic> includes strains with biocontrol and/or biostimulant potential and is recognized as a source of genes with biotechnological value. In a previous study the Kelch domain protein, encoded by the <italic>Thkel1</italic> gene of <italic>Trichoderma harzianum</italic> T34, was found to confer tolerance to salt stress when expressed in plants of <italic>Arabidopsis thaliana</italic>. In the present work, we have overexpressed <italic>Thkel1</italic> in rapeseed plants in order to generate an additional biotechnological tool for analyzing the role of this gene in <italic>Trichoderma</italic>-plant interactions. The overexpression of this gene in Brassicaceae plants improves responses to pathogens through the induction of systemic defenses mediated by jasmonic acid, facilitates root colonization by modulating the myrosinase activity, and, as a result, increases plant productivity. These effects were also observed in <italic>Thkel1</italic> overexpressing plants subjected to abiotic stress conditions. Additionally, the differences detected in root colonization levels by <italic>T. harzianum</italic> wild type and <italic>Thkel1</italic> silenced transformants between <italic>Arabidopsis</italic> or rapeseed and tomato plants indicate that ThKEL1 interacts in different ways in Brassicaceae and non-Brassicaceae plants.</p>