AUTHOR=Aamir Mohd , Kashyap Sarvesh Pratap , Zehra Andleeb , Dubey Manish Kumar , Singh Vinay Kumar , Ansari Waquar Akhtar , Upadhyay Ram S. , Singh Surendra 

TITLE=Trichoderma erinaceum Bio-Priming Modulates the WRKYs Defense Programming in Tomato Against the Fusarium oxysporum f. sp. lycopersici (Fol) Challenged Condition

JOURNAL=Frontiers in Plant Science

VOLUME=10

YEAR=2019

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2019.00911

DOI=10.3389/fpls.2019.00911

ISSN=1664-462X

ABSTRACT=<p>The beneficial association and interaction of rhizocompetent microorganisms are widely used for plant biofertilization and amelioration of stress-induced damage in plants. To explore the regulatory mechanism involved in plant defense while associating with beneficial microbial species, and their interplay when co-inoculated with pathogens, we evaluated the response of tomato defense-related <italic>WRKY</italic> gene transcripts. The present study was carried out to examine the qRT–PCR-based relative quantification of differentially expressed defense-related genes in tomato (<italic>Solanum lycopersicum</italic> L.; variety S-22) primed with <italic>Trichoderma erinaceum</italic> against the vascular wilt pathogen (<italic>Fusarium oxysporum</italic> f. sp. <italic>lycopersici</italic>). The tissue-specific and time-bound expression profile changes under the four different treatments “(unprimed, <italic>Fol</italic> challenged, <italic>T. erinaceum</italic> primed and <italic>Fol</italic>+ <italic>T. erinaceum</italic>)” revealed that the highest upregulation was observed in the transcript profile of <italic>SlWRKY31</italic> (root) and <italic>SlWRKY37</italic> (leaf) in <italic>T. erinaceum</italic> bioprimed treated plants at 24 h with 16.51- and 14.07-fold increase, respectively. In contrast, <italic>SlWRKY4</italic> showed downregulation with the highest repression in <italic>T. erinaceum</italic> bioprimed root (24 h) and leaf (48 h) tissue samples with 0.03 and 0.08 fold decrease, respectively. Qualitative expression of PR proteins (chitinases and glucanases) was found elicited in <italic>T. erinaceum</italic> primed plants. However, the antioxidative activity of tomato superoxide dismutase and catalase increased with the highest upregulation of <italic>SOD</italic> and <italic>SlGPX1</italic> in <italic>Fol + T. erinaceum</italic> treatments. We observed that these expression changes were accompanied by 32.06% lesser H<sub>2</sub>O<sub>2</sub> production in <italic>T. erinaceum</italic> bioprimed samples. The aggravated defense response in all the treated conditions was also reflected by an increased lignified stem tissues. Overall, we conclude that <italic>T. erinaceum</italic> bio-priming modulated the defense transcriptome of tomato after the <italic>Fol</italic> challenged conditions, and were accompanied by enhanced accumulation of defense-related <italic>WRKY</italic> transcripts, increased antioxidative enzyme activities, and the reinforcements through a higher number of lignified cell layers.</p>