Changes in pathogenesis-related gene expression in response to bioformulations in the apoplast of maize leaves against <i>Fusarium oxysporum</i>

<p>In present study, we initially tested four different plant species <i>Aristolochia indica</i> (leaf)<i>, Cuscuta pedicellata</i> (stem)<i>, Melilotus indicus</i> (leaf) and <i>Tribulus terresteris</i> (leaf and fruit) for their antifungal potential against <i>F. oxysporum.</i> Among the studied plant species, <i>T. terresteris</i> (fruit) and <i>C. pedicellate</i> showed the maximum antifungal potential by 92% and 89%, respectively. We then investigated the potential of CHI, MeJA, and plant extracts (<i>C. pedicellate</i> and <i>T. terristris</i>) alone as well as in combinations in pot experiment. Treatments with the extracts of <i>C. pedicellata</i> and <i>T. terresteris</i> in combination with MeJA resulted in decrease in disease severity by 93% and 89%, respectively, and enhanced the plant growth. We observed significant elevated levels of expression of pathogenesis-related (PR-1) proteins (β-1-3-glucanase, chitinase, phenyl-alanine ammonia lyase (PAL), lipoxygenase, lipid transfer protein and PR protein) and defense enzymes (β-1-3-glucanase, chitinase, peroxidase, polyphenoloxidase and PAL) in the CHI and MeJA in combination with plant extracts-treated plants for defense signaling pathways in the apoplast of maize leaves compared to the inoculated control. We found CHI in combination with <i>C. pedicellata</i> most effectively induced the plant defense mechanisms against <i>F. oxysporum</i> through increased induction in the level of expression of PR-proteins.</p>