The Effect of Rhizobium and N Fertilizer on Growth and Yield of Black Soybean (Glycine max (L) Merril)

The study aimed to find out the growth response and yield of black soybeans (Glycine max (L) Merril) on Rhizobium inoculation, N fertilization and the interaction of both. This research was carried out in the Experimental Farm of the Faculty of Agriculture, Jenderal Sudirman University on May to October 2018. This study arranged in factorial completely randomized design (FCRD) with two factors. The first factor is the species rhizobium (R) consisting of Rhizobium radiobacter, Rhizobium pusenses, Rhizobium nepotum. The second factor is the N Fertilizer (N) consisting of 0, 25%, 50%, 75%, and 100% fertilizer dosage of N recommendations (100% dosage recommendation is similar to 120 kg). Variables observed were plant height, number of leaves, leaf area, stem diameter, dry weight of root, seed weight, 100 seed weight, number of pods, pod weight, and pod weight per plant. The results showed that: Application of the type of Rhizobium neoptum isolate gave the best results on leaf area, pod weight and number of pods, The treatment of 25% N fertilizer dosage recommendations gave the best results on variable stem diameter and pod weights, N 50% fertilizer dosage recommendations gave the best results on plant height, leaf area, number of leaves and number of pods. There was no interaction between the type of isolate and dose of N. fertilizer.