Seed Treatment of Green Gram with Molybdenum and Cobalt: Effect on Nodulation, Biomass Production and N Uptake in an Acid Soil

A field experiment on seed treatment of green gram with micronutrients (0.16 mg Mo and 0.008 mg Co per gram of seed as sodium molybdate and cobalt chloride, respectively) and Rhizobium culture showed significant increase in nodule number, nodule weight, N concentration, leghaemoglobin content, grain yield, N uptake and total biomass production over uninoculated treatment in a moderately acid soil. The grain yield and total biomass increased by 74.5 and 97.5 per cent, respectively over a control yield of 3.4 and 7.9 q ha⁻¹. The total N gain through micronutrient and inoculation treatment was 45.4 kg ha⁻¹ and additional N uptake was 24 kg ha⁻¹. The APR and AKR were 14.4 and 38.2 per cent which resulted in 15.3 and 8.3 kg grain per kg of applied P and K, respectively.