Effect of Different Rates of Phosphorus and Sulphur Fertilization on the Growth, Yield, and Protein Content of Mung Bean (Vigna radiata L.)

This study aimed to evaluate the effects of different rates of phosphorus (P) and sulphur (S) on the growth, yield, and protein content of mung bean (Vigna radiata L.), to determine the combined effects, and to identify the optimal combination for maximum productivity and protein content of mung bean. The field experiment was conducted at the Department of Soil and Water Science Farm, Yezin Agricultural University, Myanmar, during the monsoon season from May to August in 2025, and post-monsoon season from October 2025 to January 2026. The experiment was laid out in a 4 × 3 factorial arrangement in a randomized complete block design (RCBD) with three replications. Four P levels (0, 30, 60, and 90 kg P₂O₅ ha⁻¹) and three S levels (0, 20, and 40 kg S ha⁻¹) were tested. Growth parameters (plant height, crop growth rate (CGR), and branches plant-1), yield components (pods plant-1, seeds pod-1, and 100-grain weight), grain yield, and protein content were recorded. The tallest plants (71.60 and 60.40 cm), maximum CGR (15.56 and 13.08 g m-2 day-1), branches plant-1 (2.20 and 2.0), pods plant-1 (30.73 and 27.10), seeds pod-1 (12.47 and 11.23), highest yield (1632.20 and 1712.20 kg ha-1 ) and protein content (24.33 and 25.37 %) were recorded at the application of 90 kg P₂O₅ ha⁻¹ + 40 kg S ha⁻¹ (P₃S₂) during both the monsoon and post-monsoon seasons. These parameters were not significantly different from those of 60 kg P₂O₅ ha⁻¹ + 20 kg S ha⁻¹ (P2S1).  Therefore, P2S₁ is suggested as the most suitable nutrient combination for maximizing mung bean productivity and protein content in the study area.