Allelopathic Potential of Datura stramonium Aqueous Extracts on Germination and Radicle Growth of Glycine max

Abstract

Allelopathic interactions play a significant role in regulating crop establishment and early seedling growth in agricultural ecosystems. Laboratory experiments were conducted to evaluate the allelopathic potential of aqueous leaf extracts of Datura stramonium on seed germination and radicle growth of Glycine max. Different concentrations of leaf extracts were prepared and applied to soybean seeds under controlled germination conditions to assess their effects on germination percentage, seedling vigor, and early root development. Results indicated a concentration-dependent inhibition of germination, with higher extract concentrations causing significant reductions in germination rate compared with the untreated control. Radicle length and seedling vigor index were markedly suppressed in treated seeds, indicating strong inhibitory effects on early root elongation. Phytotoxic responses were attributed to the presence of secondary metabolites such as alkaloids, phenolics, and terpenoids in D. stramonium leaf extracts, which may interfere with enzymatic activity, cell division, and water uptake during germination. Morphological observations revealed reduced seedling vigor, shortened radicles, and impaired plumule development at higher treatment levels. Lower extract concentrations showed comparatively moderate effects, suggesting dose-dependent allelopathic activity. The findings demonstrate that D. stramonium possesses strong allelopathic potential capable of influencing the early growth stages of G. max. Such interactions may have important implications for weed–crop competition in field conditions where D. stramonium co-occurs with soybean crops. Understanding these biochemical interactions is essential for developing integrated weed management strategies and evaluating the ecological impact of allelopathic weeds in agroecosystems.