Trehalose: A mycogenic cell wall elicitor elicit resistance against leaf spot disease of broccoli and acts as a plant growth regulator

•Mycogenic cell wall elicitor was isolated from trichoderma atroviride.•The isolated elicitor was identified as trehalose by LC-MS analysis.•Seed priming with elicitor enhanced early germination and vigour.•Primed plants induced resistance against leaf spot disease of brocolli.•Trehalose sugar act as a bio-stimulant for growth promotion and plant defence. Elicitors are biochemicals, and the cell wall-derived elicitors from fungi can trigger defence mechanisms in plants by increasing the phytoalexin accumulation when they encounter the pathogens. The main objective of this research was to purify and characterize a cell wall elicitor from Trichoderma atroviride (TaCWE) and evaluate the seed priming effect of that elicitor for inducing systemic resistance in broccoli plants against leaf spot disease. Amongst the tested TaCWE concentrations of the seed priming (5, 10, & 25 mg ml−1), 10.0 mg ml−1 showed significantly (P