Allelopathic Potential of the Essential Oil of Wild Marigold (Tagetes minuta L.) Against Some Invasive Weeds

Abstract

Tagetes minuta is an aromatic plant native to Tropical America. It exhibits wide range of biological activity against insects, nematodes, microbes including medicinal properties. It also creates nuisance for agricultural land. This may be attributed to its allelopathic properties. Therefore, the present study investigated the allelopathic potential of volatile oil of T. minuta on other invasive weeds - Chenopodium murale L., Phalaris minor Retz. and Amaranthus viridis L. It was observed that the volatile oil of T. minuta significantly reduced the germination, growth, chlorophyll content and respiratory ability of recipient weeds in a dose dependent manner. Mitotic studies revealed a complete arrest of mitotic activity in cells of treated root tips of Allium cepa with various aberrations like distorted, trinucleolated and binucleated cells. Thus, it can be concluded that the volatile oil of T. minuta shows allelopathic potential on other plants and this property could be further explored for weed management.