OPTIMIZING DEFICIT IRRIGATION AND SOIL MULCH ADAPTATION STRATEGIES FOR COTTON (GOSSYPIUM HIRSUTUM L.) PRODUCTIVITY AND ECONOMIC GAINS UNDER WATER-LIMITED DRY CLIMATIC CONDITIONS

Abstract

Cotton is a major oil and fiber crop in many countries around the globe. The primary constraint in cotton cultivation is water scarcity. Thus, the adoption of economical and best management practices (BMP) are needed to improve productivity on a sustainable irrigation basis. We investigated the economic and agronomic benefits of sustainable irrigation [(control and partial rhizosphere drying (PRD)] and BMP (no-mulched, black plastic, wheat straw, and cotton stick) treatments, to find a combination of strategies towards a higher yield and economic return. Our findings revealed that PRD irrigation significantly increased cotton yield by 35%, improved water use efficiency (WUE) by 21%, and enhanced the economic returns of cotton production. Maximum expenditure was found in control irrigation treatment with wheat straw mulch. The control treatment, which involved full irrigation with cotton and wheat straw mulch, exhibited the highest recorded benefit-cost ratio (BCR) of 2.09:1. Conversely, the treatment that utilized PRD without the application of mulch material demonstrated the lowest BCR of 1.05:1. Maximum net field benefit (174514 Rs/ha) was recorded in a combination of control irrigation with wheat straw mulch. Among the PRD treatments, the maximum net field benefit was recorded in PRD with wheat straw mulch (89179 Rs/ha) followed by PRD with black plastic mulch (72236 Rs/ha), and minimum (84085 Rs/ha) net field benefit was recorded in PRD with cotton sticks mulch. The results showed that the combination of sustainable irrigation with BMP is a reliable strategy to increase WUE and economic gains to meet sustainable development goals in the era of global warming, climate change, and water crisis.