INFLUENCE OF MOLYBDENUM IN ASSOCIATION WITH RHIZOBIUM ON ENHANCED BIOLOGICAL NITROGEN FIXATION, GROWTH AND YIELD OF SOYBEAN UNDER DRIP IRRIGATION SYSTEM

Soybean ( Glycine max) is one of the most important legume crops which fix atmospheric nitrogen in symbiotic association with bacteria through nodules. A study was conducted to investigate the effect of molybdenum and pre-inoculation of Rhizobium on biological nitrogen fixation and yield of soybean under drip irrigation system. A total of six treatments were used in this experiment which included control, 1 kg of Mo/ha, 1.5 kg of Mo/ha, 10 kg of Mo/ha, Rhizobium isolate UPMR020, UPMR020 + 1 kg of Mo/ha, UPMR020 + 1.5 kg of Mo/ha, UPMR020 + 10 kg of Mo/ha. Application of 1kg of Mo/ha along with bacterial inoculum produced the highest (51) nodules per plant. This treatment also produced the highest nodule's weight (199 mg/plant) and plant dry weight (72 g/ plant). Application of 1 kg of Mo/ha in association of UPMR020, produced significantly high yield (29.46 g/plant) compared to control which produced only 9.15 g/plant, thus indicating the potential of this treatment to be used for soybean with drip irrigation system. Key words: Glycine max, Growth, Molybdenum, Nodulation, Rhizobium, Yields