Potential utilization of dried powder of Tagetes minuta as a natural herbicide for managing rice weeds

Tagetes minuta is an aromatic essential plant with wide range of biological activity including medicinal properties. A study was undertaken to explore the potential herbicidal activity of Tagetes minuta leaf powder (at 1, 2, and 4 t ha−1) towards two invasive weeds—Echinochloa crus-galli and Cyperus rotundus—of rice fields. It was observed that T. minuta leaf powder applied to rice field soil significantly reduced emergence and growth of both the weed species in pots under greenhouse and in rice field plots. At 1 and 2 t ha−1 dose of application, emergence and growth of weeds was severally affected, whereas there was no effect on the growth and yield attributes of rice. Rather, at this dose of application yield of rice increased significantly and the effect was similar to that observed with the herbicidal application under field conditions. Based on the study, it could be concluded that T. minuta possesses weed-suppressing ability and could be used as a natural herbicide.