strengthen understanding of various types of manures and fertilizers, their
manufacturing and application methodology.
focus on soil fertility and productivity with emphasis on nutrient deficiency
disorders and remedies.
acquaint with the nutrient absorption mechanism, outcome of nutrient
fertilizers applied to the soil and critical levels of nutrient elements in
soil and plants.
q Manures are organic materials added to the
soil to increase crop production.
q They are biological in origin.
q The organic matter content is bulky and
large and the nutrient content is small. They have the following effect on the
1. They supply nutrients to the soil. Since
the manures contain nutrients in small quantities they have to be used in bulk
2. Since the manure contains a lot of organic
matter, it increases the water holding capacity in sandy soils and drainage in
Farm yard manure
q This is the decomposed mixture of excreta
(dung) and urine of farm animals like cow, horse, goat and sheep along with
leftover hay and fodder.
q They are readymade manures and contain
nitrogen, phosphorus and potassium.
q Farmyard manure when collected in the
field and stored in an exposed condition over a long period shows considerable
loss of ammonia which is a loss of fertilizing value. To prevent this loss the
dung is stored in pits which are about a metre deep. When the pits are filled to
the top, the surface is sealed with mud slurry. The manure is ready for use in
about 4-5 months.
q This consists of a variety of farm wastes
such as farm weeds, straw, sugarcane refuse, rotting vegetables, kitchen
wastes, crop stubble, groundnut and rice husk.
q Composting is a biological process in which
aerobic and anaerobic microorganisms decompose organic matter.
trench of suitable size 4-5 m long, 1.5 to 1.8 m broad and 1.0 to 1.8 m deep is
dug. A layer of well mixed refuse of about 30 cm thickness is spread in the
pit. A slurry of cow dung, earth and water is poured over this layer to keep it
moist. Another layer of the mixed refuse is spread in the pit till the heap
rises to a height of 45 to 60 cm above ground level.
Nutrient content of farm and town compost
q Green manuring is the practice of growing
and ploughing in, the green crops, into the soil.
q It is a cheap and effective method that
increases soil fertility as it can supplement farmyard and other organic
manures and is more cost effective.
q Green manures add nitrogen and organic
matter to the soil for improving crop productivity.
q They also improve soil aeration and
Plants used as green manure are:
English and Hindi names
Sunn hemp (Sanai)
Egyptian clover (Berseem)
Cluster bean (Gaur ki phalli)
q This type of manuring is used in fields in
which crops like rice, maize, sugarcane, cotton, wheat etc., which require high
nutrient input are raised. There is 30 – 50% increase in the crop yield by
using green manure.
q The green manure crops are grown in the
field for about 6 – 8 weeks and ploughed into the soil during the flowering
stage. The plants are allowed to remain buried for about 1 – 2 months. During
this period, the plant gets totally decomposed. The soil is then tilled and the
next food crop is sowed. By alternating the green manure crop with food crop
the nitrogen and organic content of the soil is maintained.
q Vermicompost is a type of compost made by
earthworms and microorganisms as they feed on organic wastes.
q The compost thus produced is mainly worm
excreta and finely ground soil.
q Organic wastes can be collected and fed on
by worms so that the end product is the broken down version of the original
q Worm castings (excreta) in the
vermicompost have nutrients that are 97% utilizable by plants.
q The biofertilizers containing biological
nitrogen fixing organisms are of utmost importance in agriculture Advantages Of
help in the establishment and growth of crop plants and trees.
enhance biomass production and grain yields by 10-20 percent.
are useful in sustainable agriculture.
are suitable in organic farming.
play an important role in Agrotorestry/ Silvi- pastaural system.
TYPES OF BIOFERTILIZERS
q Rhizobium:-Most widely used biofertilizer is
Rhizobium which colonizes the roots of specific legumes to form tumor like
growths called root nodules. These nodules act as factories of ammonia
production. The Rhizobium – legume association can fix up to 100-300 KG/N. in
one crop season.
q Azotobacter:-Application of azotobacter has been found
to increase yield of wheat, rice, maize, pearl-millet and sorghum by 0-30 p.c.
over control. Apart from nitrogen this organism is also capable of producing
antifungal and antibacterial compounds, hormones.
To acquaint the students with
manure and fertilizers, their classification and manufacturing.
fertilizer or Single nutrient (“straight”) fertilizers:-
q These are the fertilizers which supply
only a single plant nutrient.
ü The main nitrogen-based straight
fertilizer is ammonia or its solutions. Ammonium nitrate (NH4NO3) is
also widely used. Urea is another popular source of
nitrogen, having the advantage that it is a solid and non-explosive, unlike
ammonia and ammonium nitrate, respectively.
ü The main straight phosphate fertilizers
are the superphosphates. “Single superphosphate” (SSP)
consists of 14–18% P2O5, again in the form of Ca(H2PO4)2,
but also phosphogypsum (CaSO4 · 2 H2O). Triple superphosphate (TSP) typically consists of 44-48%
of P2O5 and no gypsum. A mixture of single superphosphate
and triple superphosphate is called double superphosphate
fertilizer or Multinutrient fertilizers:-
q These fertilizers are the most common.
They consist of two or more nutrient components.
q Fertilizers such as binary
fertilizers(NP,NK,PK),NPK fertilizers,micronutrient fertilizers comes under
(NP, NK, PK) fertilizers:-Major
two-component fertilizers provide both nitrogen and phosphorus to the plants.
These are called NP fertilizers. The main NP fertilizers are monoammonium phosphate(MAP) and diammonium phosphate (DAP). The active ingredient in MAP
is NH4H2PO4. The active ingredient in DAP is
(NH4)2HPO4. About 85% of MAP and DAP
fertilizers are soluble in water.
fertilizers are three-component fertilizers providing nitrogen, phosphorus, and
represents the percentage of nitrogen in the product; the P represents the
percentage of P2O5; the K represents the percentage of K2O.
Fertilizers do not actually contain P2O5 or
K2O, but the system is a conventional shorthand for the amount of
the phosphorus (P) or potassium (K) in a fertilizer
main micronutrients include sources of iron, manganese, molybdenum, zinc, and copper.
needs depend on the plant. For example, sugarbeets appear to
require boron, and legumes require cobalt
Biological process in which aerobic and
anaerobic microorganism decompose organic matter and narrow down the C/N ratio
of substrate used.
Final product formed is amorphous brown to
dark brown humified material known as compost.
Compost is a microbiologically
well decomposed black to brown amorphous
More stable and well rotten
High organic matter
High proportion of major
Free from pathogens
Mesophillic / Low active phase
Maturity / Stabilization phase
Factors affecting rate of composting
C- energy source
N- cell building
30:1 to 35:1
Addition of nitrogen source such as legume residue,
aquatic weeds, slaughter house waste and green leaves etc enhance microbial
activity and thus increase decomposition rate
FARM YARD MANURE
FYM is a mixture of the solid and liquid
excreta of farm animals along with the litter (i.e. the materials used for
bedding purposes of cattle) and left over material from roughages or the fodder
fed to the cattle.
Deficiency in Plants
Macronutrients are needed in
relatively large amounts by plants.
Macronutrients are needed in
relatively small amounts by plants.
They are usually supplied by
Nutrient Deficiency Symptoms
Nutrient deficiency symptoms usually appear on the plant when one
or more nutrients are in short supply.
In many cases, deficiency may occur because an added nutrient is
not in the form the plant can use.
Deficiency symptoms for specific elements are included on the
“Key to Nutrient Disorders”.
fertility- approaches to soil fertility evaluation, critical level of nutrients
fertility : is concerned with the inherent capacity of soil to provide nutrients
in adequate amounts and in proper balance for the growth of specified plants
when other factors such as light, moisture, temperature and the physical
condition of the soil are favourable.
for soil fertility evaluation : The
wide variety of diagnostic techniques used so far can be broadly grouped into
1) Soil Analysis
2) Plant Analysis
3) Biological methods
4) Visual symptoms of nutrient deficiency
Essential, functional and beneficial elements
A nutrient element is one that is required to complete the life
cycle of the organism and its relative deficiency produces specific deficiency
Beneficial elements are the mineral elements which at very low
concentrations and often under specific conditions have been shown to stimulate
growth of certain plants, but are not essential or which are essential only for
certain plant species or under specific conditions. Eg. Selenium, nickel,
This term is defined as an element that play a role in plant
metabolism, whether or not its role is
specific. Eg. Na, Co, Si, V + 17
essential nutrient element
Trace element is an element found in low concentration, perhaps
less than 1 ppm or still less in soil, plant and water.
Elements needed by the plant without which it will not be able to
survive are called essential nutrients.
Criteria of essentiality
For an element to be regarded as an essential nutrient, it must
satisfy the following criteria:
as propounded by Arnon & Stout(1939):
A deficiency of an
essential nutrient element makes it impossible for the plant to complete
the vegetative or reproductive stage of its life-cycle.
The deficiency is specific
to the element and can be prevented or corrected only by supplying that
3. The element is involved
directly in the nutrition of the plant, quite apart from its possible
effects in correcting some microbiological or chemical conditions of the
soil or other culture medium.
The 17 nutrient recognized essential for plant growth are:
Carbon(C) , Hydrogen (H), oxygen (O), Nitrogen(N), Phosphorous(P),
Potassium(K), Calcium(Ca), Magnesium(Mg), Sulphur (S),Iron(Fe), Manganese(Mn),
Zinc (Zn), Boron(B), Molybdenum(Mo), Chlorine(Cl) and Nickel (Ni).
It may be defined as to a
situation in which a crop requires more of a given nutrient element without
exhibiting deficiency symptoms on plants. The concentration of an element is
above the deficiency level but still considerably below that required to permit
the most profitable crop performance.
Forms of nutrient element
absorbed by the plants
Essential plant nutrients
Forms of uptake
C, H, O, N, S
CO2, HCO3, H2O, O2, NO3, NH4,
N2, SO, SO2
Major constituents of organic
material, essential elements of atomic groups which are essential in
enzymatic process, assimilation by oxidation-reduction reaction
P, B, Si
Phosphates, boric acid or
borate, silicate from soil solution
Esterification with native
alcohol groups in plants, the phosphate esters are involved in energy
K, Na, Mg, Ca, Mn, Cl
K+, Na+, Mg+2, Ca+2, Mn+2,
Non specific functions
establishing osmotic potentials, more specific reactions in which the ion
bring about optimum confirmation of an enzyme protein. Bridging of reaction
partners, balancing anions, controlling permeability and electro-potentials.
Fe, Cu, Zn, Mo
Fe+2/Fe+3, Cu+2, Zn+2,
Molybdate ion or in the form of chelates
Present predominantly in
chelated form incorporated in
prosthetic groups, enable electron transfer by valency change.
Capacity of a soil to function
within ecosystem boundaries to sustain biological productivity, maintain
environmental quality and promote plant and animal health.
In the context of agriculture,
it may refer to its ability to sustain productivity.
A healthy soil would ensure
proper retention and release of water and nutrients, promote and sustain root
growth, maintain soil biotic habitat, respond to management and resist
Food grain production and
Declining Fertilizer Response
Declining Nutrient Response
Integrated Nutrient Management (INM) – Panacea
for soil health and productivity
INM envisaging conjunctive use
of chemical fertilizers, organic manures and biofertilizers enhances nutrient
use efficiency, soil health, crop yields and profitability
Need to augment supplies of
organic manures, fortified, coated & customized fertilizers supplying
secondary and micronutrients, biofertilizers and soil amendments to have INM on
a sound footing.
Site specific nutrient
Fertilizers Policy Measures
Nutrient Based Pricing and
The pricing of fertilizers and subsidy on them to be fixed as per nutrient
content and not product wise.
The move to encourage use of complexes
and broaden the basket of fertilizers for balanced fertilizer use
The new pricing mechanism would
reduce dependence on DAP.
The SSP containing 11% sulphur
to be promoted to correct wide spread sulphur deficiency in soils besides a P
To acquaint the students with manure and
fertilizers, their classification and manufacturing.
To provide the basic knowledge of soil
fertility and productivity, nutrient deficiency and toxicity symptoms in plants along with remedial
To acquaint the students about forms of
nutrients, their absorption mechanisms and transformation of nutrient
fertilizers after their application in soil.