Integrated nutrient management in soils for improving crop productivity
agriculture largely depends on the use of high cost inputs such as chemical fertilizers,
pesticides, herbicides, improved seeds, assured irrigation, scientific management and
labour saving but energy intensive farm machinery. The application of such high input
technologies increased the production but there is growing concern over the adverse
effects of the use of chemicals and soil productivity and environment quality. When
population pressure was low, mono-cropping was a rule, with the increase in population
various multiple cropping system have become popular.
from the use of single nutrient, application of multi-nutrient has adopted. Because no
single source of nutrient can satisfy the need of all the essential elements that crop
needs for growth and development. Nutrient management in multiple cropping system is more
efficient than in individual crop because there is a residual effect of nutrients for e.g.
phosphatic fertilizer and organic sources of plant nutrients.
the productivity of different crops and cropping systems, efficient nutrient management is
vital. There is a need to develop more efficient, economic and integrated system of
nutrient management for realizing high crop productivity without diminishing soil
strategy may be useful in nutrient management. First, to continue to encourage the use of
fertilizer for a faster growth in agriculture and second, to popularize the use of
recycled crop residues, green manures, use of compost (both urban and rural) and
biofertilizers as a supplementary source of nutrients, in conjunction with chemical form
of plant nutrients. There is need to add plant nutrients to the soil on the basis of soil
fertility states. The application of nutrients according to
soil-test-based-fertility-assessment ensures better efficiency and improved profitability.
Principle: (a) basic soil fertility and climate. (b) nature of crop in cropping system.
(c) atleast 30% of the total nutrient levels NPK in organic form.
sources of nutrients are supplementary to chemical fertilizers and use of biofertilizers
considered as environment friendly, in terms of protecting the quality of underground
waters, soil property and environment in general. Complete depends on organic sources can
sustained a yield target equivalent to that prevailed during pre green revolution era. It
would be able to meet only 1/3 of the nutrient requires for the present level of foodgrain
production, if the whole of organic resources utilised available for agricultural use.
low agricultural input environments friendly used as seed inoculation and also soil
inoculation. Inoculation of Rhizobium. Azotobactor and Azospirillum substitute,
19,22 and 20 kg N/ha, respectively. Blue green algae (BGA) applied @ 10 kg/ha gave a
saving of 20-30 kg N/ha and Azolla @ 6-12 t/ha had an N equivalent of 3-4 kg/t.
potential of rural and urban compost in India is estimated to be 800 and 16 mt
respectively. Less than 50% of the manurial potential of the livestock population is
utilised at present in crop production. The major contributor of rural compost is animal
dung, which has a potential are about 7 mt of NPK. Night soil if properly exploited can
provide about 5 mt of NPK nutrients. About 1/3 of the residue potential is available for
utilization in agricultural production about 400 mt of crop residues are produced in the
country which have potential of supplying about 7.3 mt of NPK.
practice of green manuring for improving soil fertility and supplying apart of nutrient
requirement of crop is aged old. Depending on the crop grown the N contribution by green
manure crops varies from 60-280 kg/ha. Leguminous green manures can fix large quantity of
atmospheric N2 which generally can accumulate about 100 kg N ha-1 in
50-55 days but can reach up to more than 200 kg N ha. The problem with green manure crops
is that they compete with cash crops for space, time, water and other inputs.
assess on farm and off-farm resource availability through survey related to soil and
yield target depending on the resource availability.
test based estimation of nutrient requirement with due consideration on soil amendments.
of all nutrient resources available for a given circumstances.
determine time, method, mode of application considering the type of crops involved in the
efficient soil and water conservation measures to check soil erosion, soil organic C &
soil fertility in terms of soil physical, chemical and biological properties and
average size of an operational holding is 1.57 ha. small farm size has major implications
for fertilizer and water management practices.
there are 519 soil testing laboratories. The total analysing capacity of these
laboratories is about 6.5 million samples per annum. In order to provide soil test-based
fertilizer recommendations the existing analysing capacity of the soil testing
laboratories needs to be augmented almost 15-20 times.
fertility will only be maintained and enhanced by the actions of farmers. Farmers
knowledge is essentially local, based on observation and experience within specific
farming systems and agro-ecological contexts. Hence farmers participation is important.
availability of organic resources
potential of organic resources ranges between 10.5-16.2 mt of NPK, only around
of plant nutrients can be made available for agricultural use. Average organic manure use
at present is about 2 tonnes ha-1. The coverage under green manure crop is
about 6 m ha and the use of bio-fertiliser, against a total bio-fertiliser demand of 1 mt,
the current supply is less than 10,000 tonnes. Only 25% nutrient needs of Indian
agriculture can be met by utilising various organic resources namely FYM (200 mt), crop
residue (30 mt), urban/rural wastes (10 mt) and green manuring (25 m ha).
mobilisation, processing and application, because of low nutrient content and bulkiness it
requires high labour.
awareness needs to be created among the farmers for the use of farm resources on
generation and its proper recycled and encouragement for the production of compost and
for major components
components of the system needs attention are: recycling of solid wastes and crop residues
by composting and vermi composting, more popularisation of janata bio-gas plants,
encouraging growth of legumes as part of the crop rotation for grain and fodder purposes,
using sewage sludge and effluents for agriculture, integration of green manures, green
leaf manures. BGA and azolla in rice culture.
bio-fertilizers to augment N and P supply by improving/strengthening transportation,
distribution and storage infrastructure. Also enhancement of shelf life of
development of new strains and easy technique for viability test for bio-fertilizers.
to be refined so as to reduced the time, manpower and cost of chemicals during estimation
and soil test laboratories should be strengthened and up graded for soil and plant
analysis, promoting balanced use of chemical fertilizers on soil testing and correction of
secondary and micro nutrients deficiencies in soils.
of introduction of green legumes in the cropping systems should be promoted. Use of
phospho-compost should be promoted to supplement phosphatic fertiliser to a great extent.
Research on incorporation N fixing ability in non-legumes need to be accelerated.
of appropriate soil, water and nutrient management and other agronomic practices to
maximize nutrient use efficiently and economically.