Effect of Using Fertilizer on Yield and Economic Return of Mung Bean in Sandy Loam Soil at Chai Nat Province

The research aimed to investigate how fertilizer application affects soil properties, primary nutrient uptake, yield and compare cost and return of mung bean cultivar Chainat–3 production, grown in sandy loam soil in Chai Nat province. The study used a randomized complete block design (RCBD) and included five replications. Four treatments were applied: 1. control (no fertilizer use), 2. foliar spray (Fertilizers 25–5–5 and 15–30–15 at a rate of 50 g/20 liters of water), 3. chemical fertilizer at a rate of 4.5–3–3 kg N–P2O5–K2O/rai, and 4. chemical fertilizer at the rate of 4.5–3–3 kg N–P2O5–K2O/rai + rhizobium biofertilizer. The collected data included measurements of soil properties, above-ground biomass, primary nutrient uptake, yield component, and yield. The results indicated that there were no significant differences among treatments regarding soil properties, yield components, dry matter, and nutrient uptake (p>0.05), with the except of soil organic matter. The application of chemical fertilizer at a rate of 4.5–3–3 kg N–P2O5–K2O/rai + rhizobium biofertilizer, significantly increased plant height (p<0.01) and yield (p<0.05). The experimental results showed that growing the Chainat 3 variety of mung beans in the sandy loam soil of the Doem Bang soil series requires the application of fertilizers. This can be achieved through several methods: using only foliar fertilizers (specifically, 25–5–5 and 15–30–15 formulations), applying chemical fertilizers at a rate of 4.5–3–3 kg N-P2O5-K2O/rai, or a combination of chemical fertilizers with rhizobium biofertilizer. An economic analysis indicated that the use of foliar fertilizers yielded the highest return on investment, which was calculated to be 4.20.