Allelopathic Influence of Chenopodium murale Aqueous Extracts on Early Seedling Growth of Lettuce and Radish

Abstract

Allelopathic influence of Chenopodium murale aqueous extracts on early seedling growth of lettuce (Lactuca sativa) and radish (Raphanus sativus) was investigated to assess its phytotoxic potential and implications for weed–crop interactions. Laboratory bioassays were conducted using varying concentrations of leaf and stem aqueous extracts, and their effects on germination percentage, root elongation, shoot growth, and seedling vigor index were evaluated under controlled conditions. Results indicated a concentration-dependent inhibitory effect of C. murale extracts on both test species, with higher extract concentrations causing significant reductions in germination rate and seedling growth parameters. Root growth was more sensitive than shoot growth, suggesting greater susceptibility of meristematic tissues to allelochemicals. Lettuce seedlings exhibited higher sensitivity compared to radish, indicating species-specific variation in allelopathic response. The inhibitory effects are attributed to the presence of bioactive secondary metabolites that interfere with cell division, nutrient uptake, and enzymatic activity during early growth stages. At lower concentrations, mild stimulation of certain growth parameters was occasionally observed, reflecting a hormetic response. The study highlights the strong allelopathic potential of C. murale and its role in shaping plant establishment dynamics in agroecosystems. These findings contribute to understanding weed–crop interactions and suggest the importance of managing allelopathic weed species to reduce negative impacts on crop establishment and productivity.