Growth and Yield Response of Mung Bean (Vigna radiata L.) to Different Rates of Phosphorous and Potassium Application

Abstract

This study investigated the effects of phosphorus (P) and potassium (K) fertilization rates on the growth, yield attributes, and seed yield of mung bean (Vigna radiata L.) under pre-monsoon and monsoon seasons in Myanmar. Field experiments were conducted using a two-factor randomized complete block design with three replications, comprising four P levels (P0, P20, P40, P60: 0, 20, 40, 60 kg P ha-1) and four K levels (K0, K20, K40, K60: 0, 20, 40, 60 kg K ha-1). Results demonstrated that combined P and K application significantly enhanced mung bean productivity compared to single-nutrient treatments. During the pre-monsoon season, the optimal treatment was 60 kg P ha-1 with 40 kg K ha-1 (P₆₀K₄₀), yielding 1,126.87 kg ha-1, which was statistically comparable to P₆₀K₆₀. In the monsoon season, 60 kg P ha-1 with 40 kg K ha-1 (P₆₀K₄₀) produced the highest yield (1,561.17 kg ha-1), showing no significant difference from P₆₀K₂₀ or P₆₀K₆₀. In both seasons, the combined application of P and K fertilizers significantly enhanced yield and yield components, including pods per plant and seeds per pod. While P₆₀K₄₀ is recommended for pre-monsoon cultivation, reduced K input (P₆₀K₂₀) is sufficient during the monsoon, likely due to increased nutrient solubility under wetter conditions. The findings highlight the combined application of P and K in optimizing mung bean yields compared to the single application. Therefore, to optimize mung bean production, growers should consider the combined application of P and K fertilizers rather than single applications. However, to reach a precise conclusion and recommendation, more research work on mung bean should be conducted in different agro- ecological zones.