Optimizing Cotton-Wheat System Productivity Through Resource Conserving Techniques

Cotton-wheat cropping system contributes significantly to Pakistan's food security and economy. However, the system productivity is low because of soil degrading tillage, irrational use of irrigation, and potassium which delay cotton maturity and affect succeeding wheat crop. Conservation tillage (MT) with appropriate irrigation and potassium may improve the system's productivity and stability. Experiments were conducted at Gomal University, Pakistan. Treatments included tillage (conventional (CT) and conservation tillage (MT)) and three irrigation intervals viz. 5, 4, and 3 weeks for cotton in first year, while in second year tillage was same and best irrigation interval observed in first year was kept constant. In second year besides tillage, potassium (0, 50, 100, 150, 200, and 250 kg K ha-1) was included in cotton. For succeeding wheat, treatments were tillage (MT & CT) and six irrigations applied at crown root initiation, tillering, jointing, booting, 50% spike emergence, milk and dough stage. Results revealed that MT was better than CT regarding yield and net economic return. Five-week irrigation interval increased yield, improved fiber quality, and caused earlier cotton maturity. 150 kg K ha-1 produced higher net return and benefit-cost ratio (BCR) for cotton under MT than CT. Wheat grown with MT produced higher yield, net return, and BCR when irrigated 4 times at jointing, booting, 50% spike emergence, milk and dough stage. MT accumulated more soil organic matter and total soil N than CT. The results suggest that MT with appropriate irrigation and potassium can improve cotton-wheat system productivity and economics besides conservation of resources.