Maize Grain Extract as a Plant-Derived Biostimulant for Improving Growth and Yield of Chinese Cabbage

Maize grain extract (MGE) is a low-cost plant-derived input with potential to improve crop performance. This study evaluated the effects of foliar-applied MGE on the growth and yield of Chinese cabbage (Brassica rapa var. chinensis) under field conditions in Peshawar, Pakistan. Plants were treated with MGE at 0, 50, 100, and 150 g L⁻¹ in a randomized complete block design with three replications. MGE significantly (P < 0.01) improved all measured growth and yield traits, with responses increasing with application concentration. The 150 g L⁻¹ treatment produced the highest plant weight (739.72 g) and marketable yield (56.68 t ha⁻¹), compared with 373.97 g and 28.66 t ha⁻¹ in the control, representing a 97.6% increase in yield. It also resulted in the greatest plant height, leaf development, chlorophyll content, and root length. Overall, foliar MGE showed potential as a low-cost input for enhancing Chinese cabbage productivity. Further multi-season trials with nutrient-matched controls are required to confirm its biostimulant effects.