Allelopathic influence of Parthenium aqueous leaf extract on seed germination percentage and seedling growth of different crops

A lab experiment was conducted at NAU, Navsari, Gujarat, India during the year 2024to evaluate the impact of aqueous leaf extracts of Parthenium on the germination and seedling development of rice (Oryza sativa cv. GRH-2) and green gram (Vigna radiata cv. CO 4) under controlled laboratory conditions. The experiment was laid out in CRD with six treatment and four replications. Aqueous extracts at concentrations of 2%, 4%, 6%, 8%, and 10% were applied to seeds, and their effects on germination percentage, plumule and radicle lengths, and dry matter accumulation were assessed. Results revealed a concentration-dependent inhibition, with complete suppression of germination and growth at 10% concentration. Compared to the control, significant reductions were observed even at lower concentrations, with rice showing greater sensitivity in germination, while green gram exhibited greater reductions in radicle length and biomass accumulation. The findings confirm that allelochemicals present in Parthenium notably parthenin and phenolic compounds interfere with physiological processes essential for early seedling development.