Eugenol is a phenylpropanoid with a wide range of documented biological activities. Due to its versatility, it is incorporated as an active ingredient in numerous products including those intended for agriculture. We assessed the phytotoxic potential of the vapor phase of eugenol tested at 2 and 20 µl against the seeds of five weeds, both monocots and dicots. The lowest dose was able to prevent the germination of Echinochloa oryzoides, while the highest amount fully inhibited the germination of Lolium multiflorum and Sinapis alba. Trifolium incarnatum and Vicia sativa were significantly controlled only by the effect of 20 µl of eugenol. Their germination was reduced by 58.6% and 62.1%, respectively, with values of the seedling vigour index lower by more than 80% than those of the controls. It is reasonable to think of eugenol as a lead molecule in the development of new bioformulates useful in integrated weed management programs.
Keywords: Bioactive compounds; phenylpropanoids; pre-emergence application; seed germination; seedling growth; vapor phase; weed control.