In this study, we explored the impact of vermicompost on phenylpropanoid metabolism in basil's Peltate glandular trichomes (PGTs). We tested 0, 10%, and 25% doses of solid and tea forms of vermicompost on the methylchavicol chemotype of basil. Gene expression (PAL, 4CL, EGS, EOMT, CVOMT) and phenylpropene accumulation (eugenol, chavicol, methyleugenol, methylchavicol) were analyzed
... [Show full abstract] post-treatment. Solid vermicompost (SV) at 10% and 25% doses significantly reduced EOMT and CVOMT expression and decreased methyleugenol and methylchavicol levels by up to 76% and 52%, respectively. Conversely, 10% vermicompost tea (VT) significantly increased chavicol and methyleugenol levels by 243% and 613%, respectively, and upregulated EOMT and CVOMT expression. A 25% VT dose also increased eugenol and methylchavicol levels while downregulating the same genes. Our findings indicate that VT modulates phenylpropene accumulation through gene regulation, enhancing basil's aroma and antimicrobial properties. This study underscores the utility of PGTs in plant secondary metabolism research and the potential of vermicompost in phytoremediation.