After reading this article you will learn about the concept of integrated nutrient supply to plants.
Fertilizers alone cannot meet the vast requirement of plant nutrients. This is largely because of the rising cost of fertilizers and partly because of inherent draw backs with the fertilizers themselves. It calls our attention towards the concept of “integrated nutrient supply”.
The concept of integrated nutrient supply is a broad one which embraces following considerations:
i. Nutrient cycle between the soil, the crop and the animal and atmosphere.
ii. The question of correct nutrient balance in fertilizer use including micro-nutrients.
iii. Combined use of organic manures and fertilizers i.e. at least 40% of nutrient requirement of a crop should be met in the form of organic manure.
iv. The exploitation of biological sources of nutrients.
v. The matching of nutrient supply to the clopping system as a whole and not merely to the needs of specific crops.
If the farm wastes (urine dung and crop residues) are used in biogas plants, greater part of their nitrogen content can be preserved, while large amount of organic can also be made available for improving properties.
The manurial benefits of biogas slurry are two-folds. In the first place the organic matter improves. Biological activity in the soil and promotes the stability of soil aggregates thereby improving the moisture retention capacity of the soil. Secondly, the direct nutrient effects are considerable.
Biological nitrogen fixation has a tremendous potential to meet the nutrient needs. Although bio-fertilizers are becoming popular among poor and marginal farmers but still there are miles to go in that direction. Azolla and blue-green algae have been found to replace nitrogenous fertilizer as much as 30-35 per cent.
They supply not only nitrogen but also many tonnes of organic matter (vital component of the soil) to a hectare of land. The utility of green manuring by dhaincha, sun-hemp and other crops is already well established and the practice is very popular in some parts of the country. Millions of litres of sewage effluent, if used properly, can supply handsome amount of nutrients to the soil.