The allelopathic potential of sorghum (Sorghum bicolor L. Moench) was evaluated on maize (Zea mays L.) seedlings as allelopathic influence may be inhibitory or promotive, depending upon concentration and dose. Seeds of hybrid maize (DK-919) were sown in pots containing acid-washed sand. The pots were moistened exogenously with different concentrations of sorghum leachate, viz. 100%, 50%, 25%, 10%, 5% and 3%, with and without adjuvant (Emulan @ 5%) after 7 d of seedling emergence. The seedlings were harvested 30 d after sowing. Based on the results, application of sorghum allelopathic extract (SWE) at the lowest doses (5% and 3%) without adjuvant was the most beneficial for improvement of maize seedling growth. Addition of adjuvant in sorghum allelopathic extract showed inhibitory influence on the seedling growth of maize. Maximum increase in chlorophyll, carotenoids, proteins and sugar content was observed at lower (5% and 3%) sorghum water extract concentrations. The activities of catalase, superoxide dismutase, and peroxidase were decreased at higher concentrations of sorghum allelopathic extract. Application of sorghum allelopathic extract at lower concentrations (5% and 3%) offers a pragmatic and eco-friendly option to improve the growth of maize crop.