Abstract
Volatiles produced by the leaves of medicinal plants are increasingly used as a new plant disease management strategy due to their induction of diverse antimicrobial activities, it is highly essential for the development of a new phyto-fumigant product to sustain crop production. The present study attempted to find the active role of Mentha spicata-associated volatile formulation in the suppression of the growth of Pythium aphanidematum under pot culture and field conditions. Damping off disease-causing P. aphanidermatum is a devastating disease that infects the tomato crop from seed sprouting to the seedling stage. To mitigate the damping off incidence, the nature of volatile molecules produced by M. spicata was completely suppressed during di-trophic interaction with P. aphanidermatum. Molecular docking of volatile compound reported carvone as a ligand recorded with the highest binding energy of - 8.5 kcal/mol against the target protein structure of P. aphanidermatum. Application of M. spicata immobilized vermiculite ball in tomato revealed that pathogenesis-related protein (SlPR1) (2.69 folds) and jasmonic acid signaling (SlLOX) (2.65 folds) genes were highly expressed after 48 HPT on tri-trophic interaction of pathogen inoculated tomato plants while the gene SlWRKY and SlTLP exhibited a lower level of gene expression. A significant reduction in the severity of damping off incidence was observed due to the exposure of volatiles of M. spicata in the tomato plant's raised beds with relatively abundant control of P. aphanidematum. This is the first study that attempted to develop the volatile-based formulation and its role in antifungal activities during di-trophic interaction with P. aphanidematum in tomato crops. The present study concludes that the volatiles produced from M. spicata leaves immobilized vermiculite ball could be explored for the management of soil-borne pathogens infecting vegetable crops. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s12088-023-01141-1.