Effectiveness of Reducing P Fertilizer and Adding Fish Pond Mud Waste on Growth and Yield of Soybean in Peatland

Abstract

The objective of the study was to assess the effectiveness of P fertilizer reduction and the addition of fish pond sludge waste on the growth and yield of soybean crop in peatland. Research used Complete Randomized Design factorial with two factors. The first factor was the reduction of P fertilizer from the dose of 150 kg.ha-1 consisting of 4 levels, namely P0: 100% (2.944 g/polybag), P1: 75% (2.208 g/polybag), P2: 50% (1.472 g/polybag), and P3: 25% (0.736 g/polybag). The second factor was the addition of fish pond mud waste (L) from the dose of 15 ton.ha-1 consisting of 4 levels, namely L0: 25% (73.595 g/polybag), L1: 50% (147.19 g/polybag), L2: 75% (220.78 g/polybag), and L3: 100% (294.38 g/polybag). Each treatment combination was replicated 3 times to obtain 48 experimental units. The results showed that (1) fish pond mud waste was effective to reduce the use of P fertilizer, (2) the reduction of P fertilizer up to 50% from recommendation dosage by addition of fish pond sludge waste at 75% dose of 15 ton/ha was the best combination due to providing the best plant growth and the highest P concentration of plant tissue. The highest number of pods and weight of seed obtained in the combination were 60.33 pods/plant and 7.30 g/plant, respectively.