Suboptimal nutrient and water management are major constraints to sustainable wheat production in semi-arid regions in Pakistan. The field experiment was conducted during the 2023-2024 winter season to assess the interactive effects of potassium rates and tillage management under contrasting irrigation regimes. Irrigation was assigned to the main plots and comprised of two regimes: limited irrigation which consisted of two irrigations applied at crop emergence and booting stages and full irrigation which involved four irrigations applied at emergence, tillering, booting and grain filling stages. Tillage practices were assigned to the sub-plots, comprised of three treatments: deep tillage (0-30 cm), conventional tillage (0-20 cm) and shallow tillage (0-10 cm). Four potassium (K) levels (0, 40, 80 and 120 kg K ha -1) were allocated to sub-sub plots. Deep tillage significantly improved wheat productivity by enhancing key yield components and overall grain yield compared with reduced tillage practices. Potassium rates increased yield and yield related traits up to 80 kg K ha -1 with no significant additional benefits at 120 kg K ha -1. Full irrigation further maximized grain yield and yield related components relative to limited irrigation. Notably, a significant interaction between irrigation and potassium was observed for leaf biomass and thousand grain weight which indicates that higher potassium levels were more effective under full irrigation than limited irrigation. Economic analysis supported these findings, as the highest value cost ratio (VCR = 2. 51) was recorded under full irrigation combined with deep tillage at the highest level of potassium. In conclusion, integrating deep tillage with 80 kg K ha -1 under full irrigation provides a productive and economically efficient strategy for wheat cultivation under the agro-climatic conditions of Peshawar.
Khan et al. (2026) studied this question.