Effects of Different Levels of DAP on Agronomical Characteristics and Yield of Mung bean

Phosphorus deficiency is one of the main factors restricting mung bean (Vigna radiata L.) production in many parts of the world, including Afghanistan. Therefore, a field experiment was carried out in the 2025 growing season at the Research Farm of the Faculty of Agriculture, Kabul University, to determine the influence of different diammonium phosphate (DAP) fertilizer levels on mung bean growth and yield. The experiment was arranged in a randomized complete block design (RCBD) with three replications, consisting of four DAP rates: 0, 30, 60, and 90 kg ha⁻¹. The collected growth and yield data were analyzed using analysis of variance (ANOVA), and mean comparisons were performed using the Least Significant Difference (LSD) test at a 5% probability level. The application of DAP fertilizer significantly improved plant height, shoot dry matter, number of branches, pods per plant, pod length, seeds per pod, and 100-seed weight. However, leaf number, grain weight per square meter, seed yield, and harvest index did not show significant differences among fertilizer treatments, although higher values were generally observed compared with the control treatment. The maximum seed yield (870.83 kg ha⁻¹) was obtained from the application of 60 kg DAP ha⁻¹, while the highest performance for most growth and yield-related traits was recorded under 90 kg DAP ha⁻¹. The findings suggest that DAP fertilizer application enhances mung bean growth and yield performance under the environmental conditions of Kabul. Among the tested fertilizer levels, 60 kg DAP ha⁻¹ was found to be the most effective rate for achieving higher grain yield.