CROP RESPONSE AND NUTRIENT RATIO

PREAMBLE
By 2020, India will need 294 million tonnes of food grains as against a provisional
production of 230 million tonnes in 2007-2008. Thus, an additional food grain
production of 64 million tonnes has to be achieved from the same or even lesser
land area, because some area will have to be diverted to civil works such as urban
housing, roads, railways, industrial units etc. This additional production has, therefore,
to come through efficient, judicious and balanced use of chemical fertilizer.

A NPK ratio of 4:2:1 (N:P2O5:K2O) is generally considered ideal and accepted for
macro-level monitoring of consumption of plant nutrients for the country as a whole.
However, it is difficult to trace the genesis of this NPK ratio.

After attaining independence in 1947, India’s major concern was adequate food
grains and fertilizer was considered an important tool to boost food grain production
in the country. On the recommendation of Dr. A.B. Stewart (1947) of the Macaulay
Institute of Soil Research, Scotland, UK, who was invited to India, a large number
of fertilizer trials were initiated on the farmers fields in 1951 in 7 states. Dr. Frank
W. Parker, the then Director, USAID in New Delhi and Agricultural Adviser to the
Ministry of Food and Agriculture, Govt. of India also played a key role in the
encouragement of fertilizer use in agriculture. Experiments on fertilizers rapidly
extended all over India under TCM scheme and in 1956, a Coordinated Agronomic
Experiments Scheme was launched for conducting a large number of on-farm trials
(about 15000 per year) and replicated experiments at research centres known as
Model Agronomic Experiments. The scheme was later named as All India Coordinated
Agronomic Experiments Scheme in 1964 and re-named as All India Coordinated
Agronomic Research Project (AICARP) in 1969. This was Pre-Green Revolution
era and only small amounts of fertilizer were used by farmers. Thus the doses were
22.4 to 44.8 kg N/P2O5/K2O per hectare. The data obtained from these on-farm trials
showed that increase in yield and response to N was much more than that to P or
K, and that the response to combined application of NPK was not positive or even
additive. A close examination of these data also showed that in irrigated wheat the
All India average increase in yield due to N, P and K fertilization was 3.7, 2.3 and
1.4 q/ha respectively, while in rice it was 3.0, 2.2 and 1.4 q/ha, respectively. This
made fertilizer N very popular with the farmers. Probably some of these data played

National Academy of Agricultural Sciences 1

a key role in deciding upon the NPK* ratio of 4:2:1. Two things were, however,
overlooked. Firstly, the yield levels were between 1 to 2 t/ha and the native soil P
and K could meet the crop requirements. Farmers also used to apply farmyard
manure on their farms. Secondly, response to P and K was much more on red and
lateritic soils than on other soils, suggesting the need for a different NPK ratio for
different soils. Post-Green Revolution trials under the same scheme brought out
that in rice response to P was as good as to N and in case of wheat, it was even
better than that to N. Response to K was much less than that to N or P. The
introduction of high yielding varieties of wheat in 1967-68 made P fertilization quite
popular in Punjab, Haryana and Western U.P. Further, response to N was higher
in presence of P and K. This all brought balanced NPK nutrition to the forefront and
farmers were quite convinced of this. The data obtained from the All India long-term
Fertilizer Experiments, however, showed that barring Ludhiana for wheat neither the
recommended fertilizer dozes nor yield or profit maximizing doses had NPK
(N:P2O5:K2O)* in 4:2:1 ratio. At Ludhiana in wheat both the yield and profit
maximizing rates of NPK application were in 4:2:1 ratio. For rice at Bhubaneshwar
having a laterite soil, the NPK ratio for yield or profit maximization ratio was 1.6:1:1
or 4:2.5:2.5. Similarly, for wheat at Ranchi having red soil the profit maximization
ratio was 2:1.5:1 or 4:3:2. These data clearly showed the need for higher P and K
application in red and lateritic soils.

The NPK needs of a farm are determined by crop and its variety, soil’s capacity to
supply these and the use efficiency of nutrients applied externally as fertilizer.
These aspects are briefly discussed.

Nutrient needs of Crops

For producing a tonne of cereal grains about 20 – 27 kg N, 8 – 19 kg P2O5 and 24
– 48 kg K2O are required, and the values are the highest for pearl millet producing
the lowest grain yield per hectare. Grain legumes remove much more N (two to four
times of that in cereals) but most of it is fixed by the Rhizobium on their roots and
very little N as fertilizer has to be applied, say, 20 – 25 kg N/ha as a starter.
However, P and K removal is higher in pulses than in cereals. Rapeseed also
removes quite a bit of N and very high amounts of K. But in none of these, crops
NPK removal is in 4:2:1 ratio. What is worth taking note is that 60 – 89% of K taken

* Throughout this Policy Paper read NPK ratio as N:P2O5:K2O ratio

2 Policy Paper 42
up by a crop remains in straw and recycling it back to soil can meet bulk of K
requirements of crops. In crops like pigeonpea about 60% of NPK remains in stover
or residue. The average NPK uptake ratio for leguminous oilseeds works out to
4:1:4, while for repeseed / mustard it is 3.2:1.6:4 and for sunflower it is 2:0.6:4,
indicating very high K removal by sunflower. Thus, oilseeds need as much K as N
fertilization. Not only crops but varieties within a crop also differ in the ratio, in which
NPK are needed to be applied. The climate can also influence the ratio, in which
NPK are needed by crop plants.

Soil as a factor on NPK uptake and its ratio in crops

Soil due to native availability of NPK and other physical, chemical and biological
properties also affects the supply and NPK uptake by crops.

Soil tests for N most commonly used in India include organic C or alkaline
permanganate oxidizable N, while for available P, Olsen’s 0.5 M sodium bi-
carbonate extractable P is most widely used. 1 M ammonium acetate extractable
or exchangeable K is the method for available K. Soils are generally classified as
low, medium and high in available nutrients. What is worth taking note, is that soil
test values are relative and not absolute values and the amounts of NPK to be
applied depends on how well a soil chemist can relate it to likely response of a crop
to be obtained on a soil, and this is where real refinement comes into picture. A
procedure for such refinement was developed by Dr. Ramamoorthy at the Indian
Agricultural Research Institute and is known as ‘Targetted Yield Concept’ and has
been widely used in Soil Test Crop Response (STCR) studies. The fertilizer dose
determined on the basis of targeted yield concept gave higher yields than those
obtained with RDF (recommended dose of fertilizer). At Hisar having sierozems
(Aridisols) K application recommended on the basis of STCR for Raya was zero,
while in Palampur having Hapludalfs (sub-montane soil) it was only 5 kg/ha as
compared to 40 kg/ha in the state RDF for toria. However, in Coimbatore having
Vertic Ustochrepts (medium black) both N and K applications on STCR basis were
much higher than state RDF for groundnut. At none of these research centres the
recommended dose on STCR basis had a NPK ratio of 4:2:1.

Application of targeted yield concept can also take into account the application of
nutrients applied through FYM or made available through biofertilizers resulting in
reduced NPK application ratio.

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Nutrient use efficiency (NUE)

NUE of nitrogen varies from 26 to 67% depending upon the crop and cropping
system. The values for apparent recovery (AR) of N are generally higher than true
recovery determined by using 15N. A general AR value of 40 – 50% may be
considered appropriate for N. For P the AR values vary from 21 to 37%, while that
for K these vary from 41 to 56%.

Calculating fertilizer application rate

The amount of N or P2O5 or K2O to be applied to a crop can be calculated from the
expression:

Nutrient to be applied = [{yield(t/ha) x nutrient uptake (kg/t)} – {nutrient available in

soil (kg/ha)}] x 100 / NUE

For example, for a crop of rice yielding 6 t/ha of grain and removing 20 kg N/t on
a soil having 60 kg available N/ha and NUE 40%, the amount of N to be applied
will be.

N to be applied (kg/ha) = [(6 x 20) – (60)] x 100/40 = 150 kg N/ha

To find out the optimum NPK ratio for different regions of the country and for
different crops a Brain Storming Session on ‘Crop Response and Nutrient Ratio’
was organized by the National Academy of Agricultural Sciences on 28th and 29th
May 2009 at New Delhi with Dr. Rajendra Prasad, Ex ICAR National Professor and
INSA Honorary Scientist as the Convener. It was attended by 30 participants from
ICAR and its institutions, State Agricultural Universities, Ministry of Agriculture and
Fertilizer Association of India.

Technical Sessions

There were four technical sessions, three on 28th May and fourth on 29th May 2009.
The first technical session was chaired by Prof. H.K. Jain, Vice President,
National Academy of Agricultural Sciences and Chancellor, Central Agricultural
University, Imphal. Professor Jain emphasized the importance of fertilizer in
augmenting food production in the country, but pointed out that the focus has to be
on the efficiency of its use rather than on the amounts applied. He mentioned that
by the end of the 20th century, the ill effects of over-fertilization on the environment
and human health were realized and the advanced countries are reducing fertilizer

4 Policy Paper 42
application, while increasing its efficiency. He re-emphasized the need for balanced
fertilization and for increasing the efficiency of fertilizer use. He also observed that
for best results district-wize fertilizer recommendation have to be worked out for
different crops. In this session four presentations were made. Prof. Sanyal observed
that while determining K fertilizer needs of crops, due attention has to be given to
the mineralogical composition of soil. Dr. Subbarao pointed out the need for
carefully analyzing the data on crop response to fertilizer, while Dr. Gill emphasized
the need for keeping the cropping system rather than individual crop in view while
making fertilizer recommendations. Dr. Venugopalan pointed out that fertilizer
recommendations in cotton have considerably changed with the introduction and
large scale cultivation of Bt cotton. He observed that as of today, specific
recommendations for Bt cotton fertilization have not been made by the states/state
agricultural universities, however, they are in the process of finalizing the
recommendations for Bt cotton based systems.

The second technical session was chaired by Dr. A.K. Singh, DDG (NRM), ICAR.
He informed the house, that soil fertility evaluation in 170 districts is being carried
out under Department of Agriculture and Cooperation, Govt. of India funded project
executed by IISS, Bhopal. He emphasized the need for finding out the nutrients
added through irrigation and rain-water, for determining the effects of biomass
burning and for finding the effects of climate on nutrient needs of crops. In this
session three presentations were made. Dr. Srinivasa Rao emphasized the need for
making the fertilizer recommendations based on exchangeable as well as non-
exchangeable K. Dr. Hegde presented data on fertilizer recommendations for
oilseeds, while Dr. Yadav presented data on fertilizer recommendations for sugarcane.

The third technical session was chaired by Dr. R.K. Gupta, Consultant (Soil
Science), National Food Security Mission, Govt. of India, New Delhi and was mostly
dedicated to examine the state fertilizer recommendations for different crops and
for working out and suggesting broad recommendations. Dr. Biswas observed that
a considerable amount of fertilizer was going to horticultural and vegetable crops.

The fourth technical session was chaired by Dr. R.L. Yadav, Director, Indian
Institute of Sugarcane Research, Lucknow. It was decided to work out and suggest
the desired NPK ratio for different agro-climatic zones and then if possible for
different crops. Since cereals account for 69% of the total NPK consumed in India,
the main emphasis was paid to them, and fertilizer recommendations worked out
for different cropping systems in different agroclimatic zones by PDCSR, Modipuram

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served as the main source. For sugarcane, cotton, oilseeds and pulses the state
fertilizer recommendations with comments from the Directors / Project Directors of
the respective commodity Institute / Directorate served as the base material for
discussion.

Pulses remove nearly half amount of K as compared to N (most N is through

Rhizobial N fixation) and some K almost equal to starter N dose (20-25 kg/ha) is
recommended in several states (Punjab, H.P., U.P., W. Bengal, Jharkhand, A.P.,
Karnataka, Kerala), while, other states do not recommend K. The general N : P2O5
: K2O ratio of 1 : 2-3 : 1 appears alright for pulses. The same N : P2O5 : K2O ratio
also seems OK for leguminous oilseeds (groundnut, soybean). Nutrient uptake data
in rapeseed-mustard show that it removes as much K as N, while in sunflower K
removal is twice that of N. However, response of rapeseed / mustard to K was nil
in Assam, W. Bengal, Gujarat, M.P. Maharashtra, Punjab and Rajasthan. Haryana,
Rajasthan and Gujarat do not recommend K application to rapeseed / mustard, (N
: P2O5 :K2O ratio of 4 : 2: 0), while Punjab and U.P. recommended a N : P2O5 : K2O
ratio of 4 : 2: 2 for rainfed and 6 : 2-3 : 2 for irrigated crop. Since sunflower is a
heavy remover of K, even more than cereals, most states recommended K
application despite the fact that response of sunflower to K was reported only from
T. Nadu. The N : P2O5 : K2O recommended for sunflower in Punjab is 4 : 2 : 2, while
in southern states (A.P. Karnataka, T. Nadu) N : P2O5 : K2O ratio in fertilizer
recommendations varies from 4 : 4 : 2 to 4 : 6 : 4 for rainfed crop and 5 : 6 : 2 to
5 : 6 : 5 for irrigated crop. But for eastern U.P. the N : P2O5 : K2O recommendation
for sugarcane is 4-5 : 2 : 2. K is not recommended for sugarcane in Haryana.
Potassium is recommended in abundant amounts in potato and tobacco in all
states.

Detailed N : P2O5 : K2O ratios for different major crops in different agroclimatic
zones are in Annexure I.

Broad Conclusions

The broad conclusion was that while the northern alluvial belt and shallow to
medium black soils in the central plateau need some potassium suggesting a N :
P2O : K2O ratio of 4:2:1, the northeastern region and coastal plains (both eastern
and western) and southern states having red and lateritic soils need a little higher
dose of K suggesting a N : P2O5 : K2O ratio of around 4 : 2 : 2. However, in western
dry regions of Rajasthan and Gujarat on deep black soils in control plateau (needs

6 Policy Paper 42
confirmation), there may be no need for K fertilization, suggesting a N : P2O : K2O
ratio of 4:2:0. On such soils K may be applied if indicated by soil test.

It was brought out in the discussion that the efficiency of even balanced NPK
fertilization remains low due to the wide-spread deficiencies of secondary (sulfur)
and micronutrients (zinc, boron, manganese, iron). In addition to these deficiencies,
soil amendments (gypsum on sodic soils and lime on acid soils) also need to be
applied. Also, in many areas over-fertilization with nitrogen is not only mining soil
of other plant nutrients but is also creating environmental and health problems such
as enriching ground water with nitrates.

It was also brought out that the nominator in all the terms used for determining
fertilizer use efficiency (agronomic efficiency or crop response ratio, recovery
efficiency, physiological efficiency, partial factor productivity) is the crop yield, and
for obtaining a good crop yield, a good agronomy package (optimum date of
sowing/transplanting, optimum seed rate / plant population, optimum spacing, depth
of planting, recommended crop variety / hybrid, good water and weed management
and efficient plant protection etc.) is a must. Nevertheless much remains to be done
in this direction.

RECOMMENDATIONS
Major recommendations emanating from the Brain Storming Session are given
under two heads, namely, (A) agenda for research and (B) policy decisions.

A. Agenda for Research

1. The present method of determining available K in soils is I M neutral

ammonium acetate exchangeable K. This method is not adequate to predict
K supplying capacity of soil, since in most studies it has been brought out that
non-exchangeable K (NEK) contributes 80-90 % of K removed by a crop. It
is, therefore, desirable to have an estimate of ‘NEK’ in a soil. Furthermore, the
‘Intermediate K’ a fraction of the NEK is independent of the amount of K
reserve (NEK) and depends rather on the clay mineral structure and its
degree of expansion. There is a gap between the ‘K-release threshold level’
and ‘K-fixation threshold level’ in soil, the latter being generally higher. The
appropriate K management practice has to evolve ways and means to
maintain the exchangeable K level in soil at an optimum intermediate between

National Academy of Agricultural Sciences 7

 these two threshold levels. It is recommended that ‘NEK’ pool of soil be
estimated as a regular soil testing protocol in addition to 1 M ammonium
acetate exchangeable K.

2. Readily available technological inputs in augmenting nutrient use efficiency

must be scaled up through supervised validation trials. Research in improving
NUE must receive coordinated action.

3. Subsoil contributes considerably towards meeting nutrient needs of plants.

However, soil testing is done only for surface soils. It is suggested that the
nutrient resources in soil profile upto a depth of 1.5 m need to be monitored
periodically and their share in meeting nutrient needs be determined. While
doing so, root growth and proliferation must also be studied. Such studies are
much more important for perennial horticultural crops and for these crops soil
sampling protocols need to be standardized keeping in view the feeding zone.

4. Fertilizer needs for conservation tillage (zero-till with residues on the surface)
need to be worked out.

5. For high yields, water and nutrient use efficiency, fertilizer application should
be optimized in relation to optimum, sub-optimum and deficit irrigation situations.

6. Fertilizer needs for conservation irrigation (drip, sprinkler etc.) need to be

worked and for different crops and soils.

7. A large number of farmers in the rice-wheat cropping system belt are burning
rice straw in the field. Although some nutrients (N, S P, B) are partly lost on
burning metallic plant nutrients (Ca, Mg, K, Fe, Zn, Cu, Mn) are left in soil.
Estimates of these nutrients are urgently needed. Also needed are estimates
of amount of C, N, S, P, B, etc lost due to burning.

8. With the combine harvesting of rice and wheat, a sizeable part of crop residue
(stubbles) is left in a field. Estimates of residues returned and nutrient content
in residue left in a field needs to be monitored.

9. Estimates of CO2 and suspended particles generated by burning rice straw in

the atmosphere, which is an environmental hazard, are urgently needed.

10. For high yields, water and nutrient use efficiency, fertilizer application should
be optimized in relation to optimum, sub-optimum and deficit irrigation situations.

8 Policy Paper 42
11. Considerable amounts of plant nutrients (specially N, K, S) may be added
through irrigation water especially through groundwater. Estimates of such
amounts of plant nutrients will help in determining the amounts to be added
externally, which will help in increasing the efficiency of plant nutrients
applied.

12. Consolidation of the knowledge generated, its synthesis and on-farm testing
of research done on Integrated Nutrient Management (INM) aiming at reducing
fertilizer application rates and increased use of green manures / dual purpose
legumes, organic manures, crop residues and biofertilizers is urgently needed.
The chief objective is to reduce direct application of chemical fertilizer and to
recycle crop residues and organic manures.

13. Synergistic effects of micronutrients with macronutrients need to be carefully

studied and Site Specific Nutrient Management (SSNM) package need to be
developed for different crops / cropping systems for different agro-climatic
zones.

B. Policy Decisions

1. A cell may be created at IASRI or NCAP to work out the optimum N : P2O5
: K2O ratio in consultation with PDCSR, Modipuram, using the data on crop
response to fertilizers from different sources (PDCSR, Crop Improvement
Projects of ICAR, Soil Test Crop Response Correlation Project, Long term
fertilizer experiments, state agricultural universities, state departments of
agriculture, ICAR institutes). These ratios may be first worked out for different
crops in 126 NARP zones. Weighted (area basis) N : P2O5 : K2O ratios may
then be worked out for different NARP zones, states and finally for the country
as a whole. This needs to be done at a regular interval.

2. All SAUs should have a well equipped laboratory for analysis of all plant
nutrients (primary, secondary and micro) in soil and plant samples. This is not
to be restricted to the analysis of available nutrients in soils but should include
total plant nutrient analysis in soil and plant samples.

3. All soil testing laboratories (STL’s) especially district and regional laboratories
in the country should be well equipped for the analysis of available macro and
micronutrients including B and Mo, which are not included in DTPA extract,
generally used for estimating available Fe, Mn, Cu and Zn. This will call for

National Academy of Agricultural Sciences 9

 additional funds, which need to be provided. Also qualified and trained staff
should be appointed in STL’s with some incentives. Further, training and
updating of the staff of STL’s in the SAU’s should be a regular feature.
Updating of equipments in the STL’s should be done as and when required
and separated funds may be earmarked for this.

4. Availability of fertilizers on time still remains a problem in several parts of the

country. Methodology of fertilizer distribution needs to be improved.

5. Quality control of fertilizers including micronutrient fertilizers has to be assured.

6. Standardization of organic manures, their preparation methods and quality

criteria needs to be done.

7. Development and production of value-added and site-specific customized

fertilizers will help in increasing the nutrient use efficiency.

8. Recycling of plant nutrients is to be promoted. Use of organic manures such

as FYM, compost, vermicompost etc. need encouragement.

9. Most of cow dung is still used as cakes for kitchen fuel purposes. However,
the cow dung cake ash contains most of the metallic plant nutrients (Fe, Mn,
Zn, Cu, K, Ca, Mg) and hence, its return to farm field will help in meeting part
requirement of these nutrients. The awareness for this needs to be created
among the farmers and the extension workers. Alternatives to cow dung
cakes as a source of kitchen fuel need to be found.

10. Short duration energy plantations to produce biomass for fodder and firewood
need to be encouraged and if possible subsidized.

11. The fertilizer subsidy must be audited with respect to NUE and long term
effects on the environment.

12. Providing subsidy to promote cultivation of legumes for green manuring or /

and grain to help in reducing nitrogen application and to overcome the
shortage of pulses in the country.

13. Agricultural extension system needs to revamped.

14. Agricultural credit, input and technology delivery systems need to be

synchronized.

10 Policy Paper 42
15. Crop insurance needs to be provided specially for small and marginal
farmers. This will encourage them to apply needed amounts of fertilizer and
other inputs.

16. Availability of good quality of seed of the recommended variety / hybrid of a

crop needs to be assured for high nutrient use efficiency.

National Academy of Agricultural Sciences 11

 Annexure I
Fertilizer recommendations and N : P2O5 : K2O ratios for different
crops / cropping system in different agroclimatic zones of India
Sno. Agroclimatic Zone Soil Crop/ N : P2O5 : Fertilization
Cropping K2O Ratio recommendation
System (N - P2O5 - K2O
kg/ ha)

1. Western Himalayas Alluvial, Rice (K) 4:2:1 120- 60-30

(J & K, H.P.) Brown-hill

Wheat 6:2:1 150-50-25

Uttarakhand Rice (R) 4:2:1 120-60-30

Wheat 5:2:0 150-60-0

2. Eastern Himalaya Alluvial, Brown Rice (K) 4:2:2 80-40-40

(Assam, W.B., hill, Red, Tarai
NE states)

Rice (R) 4:2:2 80-40-40

3. Lower Gangatic Alluvial Red Rice (K) 4:2:2 80-40-40

Plain (W.B.) Lateritic

Wheat 6:2:2 120-40-40

4. Middle Gangetic Alluvial Red Rice (K) 4:2:2 120-60-60

Plain (Eastern U.P.) & Black

Wheat 4:2:1.3 120-60-40

Sugarcane 4.5:1.5:1 180-60-40

Bihar Rice (K) 6:2:1 120-40-20

Wheat 6:3:1 120-60-20

Sugarcane 5:2.8:2 150-85-60

5. Upper Gangetic Alluvial Rice (K) 5:2:2 150-60-60

Plain (Western U.P.)

Wheat 5:2:2 150-60-60

Sugarcane 5:2:2 150-60-60

Potato 6:2:3 180-60-90

12 Policy Paper 42
 Sno. Agroclimatic Zone Soil Crop/ N : P2O5 : Fertilization
Cropping K2O Ratio recommendation
System (N - P2O5 - K2O
kg/ ha)
6. Trans Gangetic Alluvial Rice (K) 4:1:1 120-30-30
Plain (Punjab)

Wheat 4:2:1 120-60-30

Sugarcane 5:2:2 150-60-60

Cotton 3:1:0 150-50-0

(Hybrid /Bt)

G.hirsutum 2.5:1:0 75-30-0

Mustard (R) 7:2:1 100-30-15

(irrigated

Haryana Alluvial Rice (K) 4:1:1 120-30-30

Wheat 4:2:1 120-60-30

(after Rice)

P.millet 4:2:0 120-60-0

(Hybrid)

Wheat (after 5:2.7:0 150-50-0

P. millet)

Sugarcane 3:1:0 150-50-0

Cotton 5:2:2 150-60-60

(Hybrid/Bt)

G.hirsutum 2:1:0 80-40-0

7 Eastern Plateau & Hills Red & yellow,

Red & lateritic,
Mixed red &
black

Chhatisgarh Rice (K) 4:2:1-3 120-60-40

Pulses (K) 1:3:1 20-60-20

Jharkhand Maize (K) 4:2:1 80-40-20

Wheat 5:2:1 100-40-20

Eastern Maharashtra
(Bhandera region)
& part of Orissa Rice 4:2:1.3 120-60-40

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Sno. Agroclimatic Zone Soil Crop/ N : P2O5 : Fertilization
Cropping K2O Ratio recommendation
System (N - P2O5 - K2O
kg/ ha)
8. Central Plateau & Hills Alluvial Shallow
black

Madhya Pradesh Soybean 1:3:1 20-60-20

Wheat 4:2:1.3 120-60-40

U.P. (Bundel Khand) Wheat 4:3:1 80-60-20

Maharashtra Sorghum (K) 4:2:2 80-40-40

Wheat 4:2:2 100-50-50

Cotton 4:2:2 100-50-50

(Hybrid/Bt)

G.hirsutum 4:2:2 50-25-25

9. Western Plateau Black Reddish Cotton 4:2:2 100-50-50

(Maharashtra and brown (Hybrid/Bt)
Southern M.P.)

G.hirsutum 4:2:2 50-25-25

Sugarcane 2.2:1:1 250-115-115

10 Southern Plateau Red & Leteritic,

Black, Alluvial

Andhra Pradesh Rice (K) 4:2:2 120-60-60

Rice (R) 4:2:2 120-60-60

Sugarcane 0.9:0.8:1 112-100-120

Cotton 4:2:2 120-60-60

(Hybrid/Bt)

G.herbaceum 4:2:2 90-45-45

Sunflower 2:2:1 60-60-30

(rainfed)

Sunflower 2.5:3:1 75-90-30

(irrigated)

14 Policy Paper 42
 Sno. Agroclimatic Zone Soil Crop/ N : P2O5 : Fertilization
Cropping K2O Ratio recommendation
System (N - P2O5 - K2O
kg/ ha)
Karnataka Rice (K) 3:1.5:1 120-60-40

Sugarcane 1.3:0.4:1 250-75-190

Cotton 4:2:2 120-60-60

(hybrid/Bt)

G.hirsutum 4:2:2 80-40-40

G.hirsutum 4:2:2 40-20-20

Sunflower 4:6:4 35-50-35

(rainfed)

Tamil Nadu Rice (K) 4:2:2 120-60-60

Rice (R) 5:2:2 150-60-60

Sugarcane 3.5:1:2 225-60-120

Cotton 4:2:2 120-60-60

(Hybrid/Bt)

G.hirsutam 4:2:2 80-40-40

G.arboreum 4:2:2: 40-20-20

Sunflower 5:6:4 50-60-40

(Rainfed)

Sunflower 4:6:4 60-90-60

(irrigated)

11 East Coast Plains & Hills Red, Black

Coastal Alluvium

Orissa Rice (K) 4:2:2 80-40-40

Rice (R) 5:2.5:2 100-50-40

Andhra Pradesh Rice (K) 3:2:1 60-40-20

Rice (R) 6:3:2 120-60-40

Tamil Nadu Rice (K) 5:2:2 125-50-50

Rice (R) 5:2:2 150-60-60

National Academy of Agricultural Sciences 15

Sno. Agroclimatic Zone Soil Crop/ N : P2O5 : Fertilization
Cropping K2O Ratio recommendation
System (N - P2O5 - K2O
kg/ ha)
12 West Coast Plains Red, Lateritic
& Ghats Coastal
Alluvium

Kerala Rice (K) 4:2:2 90-45-45

Rice (R) 4:2:2 90-45-45

Maharashtra (Konkan) Rice (K) 4:2:1.3 120-60-40

Rice (R) 4:2:1.3 120-60-40

13 Gujarat Plains & Hills Red, Black Groundnut 1:1.6:0 15-25-0

(K)

Wheat 4:2:0 120-60-0

Northern Gujarat Cotton 4:2:0 150-80-0

(Hybrid/Bt)

G.herbaceum — 40-0-0

Southern Gujarat Cotton 4.4:1:0 220-50-0

Hybrid/Bt

14 Western Dry Region Reddish brown, Pearlmillet 3:1:0 90-30-0

(Rajasthan) Desert (K)

Wheat 3:1:0 90-30-0

Cotton 7.5:2:1 150-40-20

(Hybrid/Bt)

G.hirsutum 4:2:1 60-40-20

Sugarcane 4:1.2:1.2 200-60-60

15 Island region Coastal Alluvium Rice (K) 4:2:1.3 120-60-40

(Andaman & Nicobar) salty

1
K = Kharif; R = Rabi (K – R make a two crops a year cropping system)
2
4:2:2 is used instead of 2:1:1 to permit comparison with 4:2:1. As far as possible all ratios are
rounded up to whole numbers. Regions and crops, where K fertilization is not recommended may
receive K application if indicated by soil test.
Source: PDCS, Modipuram for cropping system; For cotton, sugarcane pulses and oilseeds state
recommendations and respective crop institutes / Directorate.

16 Policy Paper 42