Allelopathic effect of wedelia trilobata l., on the germination and growth of cicer arietinum, vigna unguiculata, and vigna radiata seedlings

Abstract

Allelopathy describes a natural process in biotic communities, wherein a plant species suppresses the growth and establishment of neighboring flora. Such plants can be used as sources of allelochemicals to control weeds. The proposed work evaluated the allelopathic activity of Wedelia trilobata L., against the seed germination and seedling growth of Cicer arietinum (chickpea), Vigna unguiculata (cowpea), and Vigna radiata (green gram) by the leaf extracts of W. trilobata L., by Petri dish bioassay. Inhibition in shoot and root growth and fresh and dry weights was tested by one-way analysis of variance. The aqueous extract of Wedelia significantly inhibited the growth of pulse seedlings with a more pronounced effect at higher concentrations. Further, bioassay-guided fractionation yielded the petroleum ether extract showing maximum growth inhibition indicating the non-polar nature of the allelopathic compound. This extract was further fractionated, and the allelo-compounds were identified by HR-LCMS-MSMS-QTOF analysis as 9-amino-nonanoic acid, colforsin, artelinic acid, Osthol, 4-Nonylphenol, Lagochilin, and Ophiobolin A. The present study suggested a promising tool for controlling weeds through allelopathic compounds isolated from Wedelia, which can be used as natural herbicides that are less disruptive to the ecosystem.