Enhancing Drought Resilience and Yield of Maize through Foliar Application of Vermicompost Derived Bio-Liquids

Abstract

Drought stress severely limits maize productivity, necessitating sustainable approaches to improve crop resilience and yield under water-deficit conditions. Therefore, a two-year field experiment was conducted during 2019 and 2020 at the research farm of the Plant Physiology Section, Ayub Agricultural Research Institute, to evaluate the effectiveness of vermicompost-derived bio-liquids in enhancing drought tolerance and productivity of maize. The experiment was arranged in a split-plot RCBD with two soil moisture levels (70% and 35% field capacity) and nine foliar-applied bio-liquid treatments, including alligator weed, alfalfa, rice straw, their combinations, water spray, and untreated control. Bio-liquids were applied at 30, 45, and 60 days after sowing. Growth, physiological, biochemical, yield, and economic parameters were recorded. Foliar application of bio-liquids significantly (p ≤ 0.05) improved leaf area index, crop growth rate, chlorophyll fluorescence, relative water content, proline accumulation, grain yield, and benefit–cost ratio under both moisture regimes. Among all treatments, 15% alligator weed bio-liquid performed best and produced the highest grain yield under drought stress (6.26 and 6.44 t ha⁻¹ during 2019 and 2020, respectively) compared with control and water spray treatments. The superior performance of alligator weed bio-liquid was attributed to its higher nutrient content and presence of beneficial growth-promoting substances. Overall, foliar application of vermicompost-derived bio-liquids, particularly alligator weed bio-liquid, proved to be an eco-friendly and economically viable strategy for improving maize productivity and drought resilience.