Enhancing the fertility of soil and the yield of soybean in a dry climatic area of Vertisol South Lombok using combination of bioorganic-phosphate and inorganic fertilizers

Abstract

Abstract Vertisol of South Lombok is the center of soybean production on Lombok Island which is productively vulnerable due to climate change. Erratic pattern of rainfall may threat the production of soybean in this dry climatic area which may be exaggerated by climate change. Therefore. it is needed efforts to maintain or even to increase the yield of soybean through adding both bioorganic and inorganic fertilizers. This study aimed to assess the effect of combination of bioorganic and inorganic fertilizer on enhancing the fertility of soil and the yield of soybean. This experiment used a randomized block design (RBD) with 4 treatments and 5 replications. The treatments were 50% of the recommended dosage of inorganic fertilizers plus 10 g per plant of bioorganic-phosphate (P1), 75% of the recommended dosage of inorganic fertilizers plus 10 g per plant of bioorganic-phosphate (P2), 100% of recommended dosage of inorganic fertilizers (P3), and control. Parameters observed consisted of soil pH, available-P. Exchangeable-K, organic-C, cation exchange capacity (CEC), base saturation (BS), and the yield of soybean. The results showed that the treatment of 75% of the recommended dosage of inorganic fertilizers plus 10 g per plant of bioorganic-phosphate (P2) increased the soil P-available from 10.71 on the control to 22.59 ppm on the P2 treatment, and resulted from the highest yield of soybean. Thus, this treatment is recommended if the combination of the fertilizers to be applied in the Vertisol South Lombok for adapting to climate change.