Plant nutrient management

Learn Grain legumes and Oil seed production with Rahul

Plant nutrient management

FYM @ 10-15 t/ha 15-20 days prior to sowing.
On soils of low inherent soil fertility, N in seed bed or a small top dressing on young plants can be beneficial and improves uptake of other nutrients as well.
Excess N usually depress the oil content and increase protein in kernels thus, for oil purpose, apply less N than those destined for eating.
P: essential for root and kernel development, increase the number, density and efficiency of root nodules.
K: relates to the availability of other nutrients (particularly Ca and Mg and also N), apparently increase the amount of pods/plant.
NPK 10-20:25-50:20-50 Kg/ha is recommended.
Ferrous Sulphate: 10 kg/ha, Sodium molybdate: 15-25 kg/ha., Zinc sulphate: 10-20 kg/ha., Borax: 5-20 kg/ha, Manganese Sulfate: 10-15 kg/ha.
In Nepal, the general recommendation in 20:40:20 kg NPK/ha.
Avoid excess B because it leads to toxicity and inhibits Fe uptake.

Irrigation Requirement

pre-sowing irrigation for uniform and better germination and seedling establishment.
Higher moisture affects elongation and penetration ability of carpophore.
Critical stages: flowering, pegging and pod formation.
Maximum requirement: at peak flowering (6-8 weeks after sowing).
For high yields, 8-9 irrigation is necessary.
Stop irrigation for the last 15-20days of maturity.

Intercultural operations

Extent of loss due to weeds: 40-50%
Normally 1-2 hand weeding; 1st at 14-21 DAS and 2nd at 45-60 DAS.
Manually operated spike toothed harrows or rotary hoe are effective as these implements are effective in weed control, improving soil aeration and creating dust mulch.
Spray Tok-E-25 @ 4 l dissolved in 600 l of water/ha as pre-emergence.
Pre-plant spray of Fluchloralin (Basalin) @ 1 kg a.i./ha dissolved in 800-1000 l of water.

Harvesting and threshing

Ready to harvest when 75% of the pods ripe or mature.
Should be done at bright sunshine days as it facilitates to dry pods and plants.
In bunch type, lift out veins from soil, left for some days in the field to dry and pod ends of plants are knocked against a cross bar to dislodge the plants.
In runner type, Veins with pods are allowed to dry and then beaten with flails and pods are separated from the beaten mass by winnowing.
Separated pods should be cured under the sun or using forced warm air to achieve 10% moisture in kernels.
Aspergillus flavus causes production of aflatoxin on groundnut kernels which are both toxic and carcinogenic.
So, drying has to be done rapidly after harvesting in order to prevent molding, aflatoxin production and other forms of deterioration.

Yield