INM also known as IPNS (Integrated Plant Nutrient System), is a system which aims at improving and maintaining soil health to sustain the desired crop productivity involving combined use of chemical fertilizers, organic manures/wastes, coupled with inputs through biological processes.
The basic objectives of INM are;
INM is based on a concept that, the crop received their nutrients from natural pathways i.e. soil, air, water and among them soil is most important and the major nutrients supplier. But, the natural pathway can’t met the total nutrient requirement of the crops which result in increasing the nutrients consumption gaps. And it has to be met immediately in-order to sustain the crop productivity at the desired level. This nutrient consumption gaps generally met either through the application of chemical fertilizers or organic manure or recombination of both. It has been found that, total removal of nutrients by the Crops in the years is more than the addition of nutrient from different sources like chemical fertilizers, FYM, compost, bio-fertilizers through other agriculture wastes which shows nutrient consumption gaps increases. If chemical fertilizers are not use judiciously, they effect the health of the soil. The chemicals fertilizers are costly and have limited supply of nutrient. There are several pollution hazards which are associated with the use of the chemical fertilizers but the organic sources has long term beneficial effects on crop productivity, on soil productivity and at the same time in-terms of protection of the environment.
Therefore, INM system is the very broaden and very efficient system of nutrient management in agriculture. There are basically four components of INM system.
It is also called chemical fertilizers. Due to nature of rapid release of nutrients, farmers use it excessively which deteriorate the health of soil. It should be applied at right time, right place and right amount to avoid losses. Farmers should select appropriate fertilizers depending on soil condition. Urea, DAP, SSP, DSP, TSP etc are the sources of inorganic fertilizers.
It is low nutrient content and slow nutrient releasing fertilizers. All the organic sources are eco-friendly and they improve soil health and increase crop productivity. FYM, compost, vermin, manure, fish meal, bone manure, dried blood, rape cake, soybean cake etc are the sources of organic fertilizers.
There are numerous bacteria, algae, fungi which improves nutrient status of soil by fixation and mobilization of nutrient in the soils. And there is sets of micro-organisms which is very use full and helpful in the decomposition of organic residues. In the process of decomposition, these organic residues release certain growth promoting hormones which is essential and very important in the growth of the crops plants. That’s why, eco-friendly bio-fertilizers are one of the most important component of INM.
Leguminous crops have the advantage and characteristics of fixing atmospheric nitrogen in the soil through bacteria which are present in nodules of leguminous crop. These crops can be used directly as green manures or they can be inter-crop with other crops or they can be included safely in the prevailing crop rotation.