Integrated nutrient management

1. Integratednutrientmanagement

2. Integrated plant nutrition system(IPNS)
Aims at maintenance of soil fertility and plant nutrient supply to an
optimum level for sustaining desired crop productivity through
optimization of benefit from all sources of plant nutrients in an
integrated manner.
Integrated plant nutrient supply system
A method to achieve objective of IPNS
Nutrient reserve in soil
(soil fertility and
fertilization)
Organic sources
INM

3. Integrated Nutrient Management(INM)
Definition:
Refers to the maintenance of soil fertility and of plant
nutrient supply at an optimum level for sustaining the
desired productivity through optimization of the benefits
from all possible sources of organic, inorganic and
biological components in an integrated manner.

4. Goals of INM
To maintain soil productivity
To ensure productive and sustainable agriculture
To reduce expenditure on costs of purchased inputs by using farm
manure and crop residues.
To utilize potential benefits of green manures, leguminous crops,
biofertilizers, indigenous sources (FYM, compost)
To prevent degradation of environment.
To meet the social and economic aspirations of farmers without
harming natural resource base of agricultural production.

5. Basic principles of INM
 Technically sound
 Ecologically stable
 Environmentally safe
 Economically viable
 Socially acceptable
 Practically feasible
 Agronomically efficient
 Sustainable Soil productivity
 Saving of Inputs (Fertilizers)
 Eco-friendly

6. Determinants of INM
Nutrient requirement of cropping system as a whole.
Soil fertility status and special management needs to overcome soil
problems, if any.
Local availability of nutrients resources (organic, inorganic and
biological sources)
Economic conditions of farmers and profitability of proposed INM
option.
Social acceptability.
Ecological considerations.
Impact on the environment

7. Basics of nutrient management in INM
Crop characteristics:
nutrient utilization
root proliferation
species and varietal difference
nutrient extraction
Soil characteristics (nutrient status, nutrient loss, SOM)
Plant nutrient effects:
type of nutrient
method of placement
time of placement
Specific nutrient considerations (N,P,K,MNs)

8. Components of INM:
 Soil nutrients/soil fertility
 Chemical fertilizers
 Organic Manures (FYM, compost, bonemeals)
 Crop residues
 Green manures
 Crop rotations with legumes

9.  Bio-fertilizers (Rhizobium, VAM, PSB, Azolla,
Azospirillum, Azotobactor, BGA)
 Cheap Nutrient supplying minerals (pyrites/rock phosphate)
 Soil amendments and industrial wastes
 Efficient crop genotypes
 Irrigation water
 Integrated pest management

10. A. Organic manures
Organic manures are available in the form of green and dry plant
residues fresh animal wastes, decomposed materials of plant and
animal origin and biologically active preparations.
When added to soil they undergo microbial decomposition. In this
process, the nutrients held in organic combinations are slowly released
in available forms
improves the availability of nutrient elements present in the soil. It also
promote the microbial and soil enzyme activities.

11. Farmyard manures
This manure is produced in the farm mainly with animal
excreta.
It is made up of the excreta of farm animals the litter or
bedding provided for them and miscellaneous farm and house hold
wastes.
Cattle dung, excreta of other animals like sheep, horses, goats,
poultry, etc. are collected and can be utilized as a manure.
Litter is a bedding material that is spread in animal houses and
the urine get absorbed into the bedding material.
Straw, sawdust, peat, dry leaves etc are used as bedding
materials.

12. Composts
Includes organic farm wastes, stubbles of crops waste straw,
sweepings, threshing floor collection, dry weeds etc.
used for augmenting the organic matter supplies and required to be
decomposed before application.
The process of decomposing wastes is called composting and the
decomposed material is called 'compost'.
Enriched form of compost-Vermicompost

13. Green manures
 Growing a crop purposely and incorporating it in the soil for
manuring is called green manuring.
 Collecting green leave from all available sources and using it for
manuring is green leaf manuring,
 Legumes alone are used as green manure crops usually.
Ex. Dhaincha, Sesbania speciosa, S. rostrata, wild Indigo (Tephrosia
purpurea), indigo (Indigofera tinctoria), Phaseolus trilobus, sunhemp,
etc.

14. Concentrated organic manures
Concentrated organic manures are the organic manures which are rich in
nutrients than bulky organic manures. Ex. guanos, fish manures, bone
meal, oil cakes, etc. can be used in integrated nutrient management.
Legume planting
Including legumes in crop rotation is a very beneficial practice. Legumes
are the plants which have nodules on their roots in which Rhizobium (a
bacteria) lives. This bacteria have the ability to fix atmospheric nitrogen
into the root nodules.
Many other free living bacteria like Azotobacter, Beizerinckia,
Clostridium, etc. and blue green algae like Anabaena, Nostoc etc. are
also beneficial in terms of BNF.

15. Bio-fertilizers
Bio-fertilizers are defined as biological preparations containing live or
latent cells of efficient strains of microbes
Includes nitrogen fixing or phosphorus mobilizing micro organisms.
also known as microbial inoculants.

16. 1. Rhizobium
The largest contribution of biological nitrogen fixation to
agriculture is derived from the symbiosis between legumes and
Rhizobium species. Inoculation with efficient strains of Rhizobium
specific to each crop is essential for the nitrogen gains and better
crop yields.
Nitrogen fixed by legume-Rhizobium symbiosis is 100- 300 kg.
nitrogen per hectare.
2. Blue green algae (BGA)
In Indian soils, the predominant genera are Anabaena, Nostoc,
Calothrix sp.
 BGA inoculation add up to 50 t/ha of organic matter and
contributes 20-30 kg. nitrogen per hectare.

17. 3. Azotobacter
Azotobacter is a free living bacteria which not only provides
nitrogen but also produces a variety of growth promoting substances
like indole acetic acid, gibberillins, B-vitamins and anti-fungal
substances.
4. Azospirillum
Inoculation of Azospirillum has shown positive response in
several field crops like sugarcane, sorghum, millets with an average
response equivalent to 15-20 kg. nitrogen per hectare.

18. 5. Mycorrhiza
Vesicular Arbuscular Mycorrhiza (VAM) belonging to the genera Glomus,
Gigaspora, Entrophospora, etc.
It enhances the phosphorus availability and also the availability of other
elements like potassium, sulphur and micronutrients like copper, zinc,
aluminum, manganese, iron, etc
Mycorrhizal colonization also allows introduced population of beneficial soil
organisms like Azotobacter, Azospirillun and phosphate solubilizing bacteria to
thrive.
Reports showed that VAM fungi can reduce fertilizer requirement by 25-30
per cent.

19. 6. Phosphatic bio-fertilizers
 Phosphate solubilizing organisms such as Pseudomonas striata,
Bacillus polymixa, Asperigillus awamori, Pencillium digitatum
etc. are capable of solubilizing native insoluble forms of P in soil
and make them available to crops in form of phosphate ion.
 Major solubilizing mechanisms include: Organic acid production,
phosphatase enzyme, siderophore secretion, extrusion of proton
etc.
 Indian Agricultural Research Institute, New Delhi has prepared
carrier based inoculant known as ''IRRI Microphos" culture using
efficient strains of P. striata and B. polymixa.

20. Other Sources
Crop residues of annual grain legumes such as green gram, Cowpea,
black gram, horse gram and soybean can be ploughed back into soil
after the grain is removed.
Waste material, in the coir industry, coir pith is a potential source of
organic manure in India. Coir pith is rich in potassium and
micronutrients such as iron, manganese, zinc and copper, high
moisture use efficiency( in dry land).
Different industrial wastes like flyash, urban garbage, saw dust,
sewage sludge, biogas slurry, basic slag and press mud can also be
used as source of nutrients in INM.

21. Specific Considerations in INM
Soil test crop response (STCR) based fertilizer application
STCR equations for each crop and soils can be used correlating soil
test values to achieve target yield.
Drip Fertigation
Ensures regular and uniform flow of water and nutrients.
Distribution of nutrients at active root zone enhancing NUE.
Reduces nutrient losses like leaching, volatilisation.
Useful for MNs
Increase availability and uptake of nutrients.

22. Foliar spray
2-3 applications at short intervals
useful for horticultural crops
conc <1-2% to avoid injury to foliages
foliar spray of UREA in apple, citrus, pineapple.
Conservation tillage
chiseling
stubble mulching
zero or minimum tillage
It maintains soil moisture level, ensures minimum disturbances to soil,
reduces soil erosion.

23. Residual fertilizer availability
Residual availability of fertilizers should be included in evaluation of
fertilizer economics through soil testing.it is maximum for immobile
elements and less for mobile elements.
Utilization of nutrients from subsoil
It depends on ability of roots to explore nutrients at subsoil.
Soil K high in surface and subsurface soil.
Subsoils are low in P and MNs, so P and MNs fertilization at surface
soil is desirable.
Planting of deep rooted crops (alfa alfa, sweet clover)

24. Site specific nutrient management (SSNM)
SSNM improves NUE by spatially distributing nutrients based on
spatial variation in yield potential, soil test levels and other spatial
data.
Based on spatial distribution of soil N,P,K fertility
recommendation map is prepared followed by application of
fertilizers by computer controlled variable rate applicator.
Uses remote sensing technology, aerial photography (NDVI map)
to study spatial variability in fertility within the field.

25. Application timing:
Nutrient application timing depends on specific nutrients, nature of
soil. Mobile nutrients should be applied just prior to peak growth
period and they require split application to maximize NUE. For
immobile nutrients preplant applications are recommended.
Placement method: Placement decisions are based on specific
nutrient and intended crops. broad casting is desirable for N fertilizers
where as band applied P increase PUE.
Band application-row crops (sorghum, wheat)
seed drilling- widely spaced crops

26. Advantages of INM
 Enhances the availability of applied as well as native soil
nutrients
 Synchronizes the nutrient demand of the crop with nutrient
supply from native and applied sources.
 Provides balanced nutrition to crops and minimizes the
antagonistic effects resulting from hidden deficiencies and nutrient
imbalance.
 Improves and sustains the physical, chemical and biological
functioning of soil.
 Minimizes the deterioration of soil, water and ecosystem by
promoting carbon sequestration, reducing nutrient losses to ground
and surface water bodies and to atmosphere

27. Constraints in adoption of INM
Non availability of FYM
Difficulties for growing green manures
Non availability of biofertilizers
Non availability of soil testing facilities
High cost of chemical fertilizers
Improper irrigation facilities
Lack of knowledge and poor advisory services
Lack of improved seeds
No access to credit facilities

28. Recent advances in INM
Soil test based nutrient management (STCR based)
Optimum leaf N for high yield in rice using LCC or chlorophyll
meter
Site specific nutrient management (SSNM) for irrigated rice
Site specific crop management or precision farming
Use of decision support system-QUEFTS, MANAGE, DSSAT