Introduction to Major Field Crops

Nutrient Management

For obtaining good yields of soybean 15-20 tons of farm yard manure or compost per hectare should be applied. Like other leguminous crops, requirement of nitrogen is substantially fulfilled from symbiotic nitrogen fixation through Rhizobium. Seed treatment with rhizobium not only enhances the yield but enriches the soil also. Rhizobium inoculation can fix 150 kg N/ha in soybean.An application of 20 kg nitrogen per hectare as a starter doseis sufficient to meet the nitrogen requirement of the crop in the initial stage.

Soybean requires relatively large quantity of phosphorus. Phosphorus is taken up by soybean plant throughout the growing season. The period of great demand starts just before the pod formation till ten days prior to seed development. A dose of 60-80 kg P2O5/ha is generally recommended for the crop.

Soybean also requires a relatively large amount of potassium. The rate of potassium uptake climbs to a peak during the period of rapid vegetative growth then slows down about the time bean begins to form. Application of 50-60 kg K2O/ha is sufficient to meet the requirement of soybean crop. The fertilizers should preferably be placed, at sowing time, about 5-7 cm away from the seed at a depth of 5-7 cm from seed level.