Bioherbicidal potential of plant species with allelopathic effects on the weed Bidens bipinnata L.

Plant species with allelopathic effects against weeds have emerged as a potential strategy for the development of ecologically friendly bioherbicides. In this study, the allelopathic effects of the plant species Dipteryx lacunifera Ducke, Ricinus communis L., Piper tuberculatum Jacq., and Jatropha gossypiifolia L. on the weed Bidens bipinnata L. were investigated. In vitro bioassays revealed that aqueous extracts of selected plant species were able to inhibit seed germination and seedling growth of B. bipinnata, highlighting the strongest allelopathic effect evidenced by R. communis. The phytotoxicity of the aqueous extracts was evaluated in pot experiments, which indicated that the foliar application of R. communis and P. tuberculatum extracts on B. bipinnata plants caused yellowing of leaves, affecting the chlorophyll content and reducing growth. The discrimination of the plant extracts by attenuated total reflectance Fourier transform mid-infrared (ATR FT-MIR) spectroscopy combined with principal component analysis (PCA) indicated the presence of allelochemical compounds, such as phenolics and terpenoids, which may be associated with allelopathic activity. Overall, this study provides valuable information about the substantial allelopathic inhibitory effects of the plant species R. communis and P. tuberculatum on the weed B. bipinnata, which may be used for the development of eco-friendly bioherbicides.