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1. 1

2. Use of Slow Release Chemical
Fertilizers in Crop Production
Speaker
IRFAN
MOHAMMAD
M.Sc final(Ag.)
2
Seminar incharge
Dr. Rajhans Verma

3. CONTENTS
3
 Introduction
 Why need slow release chemical fertilizers ?
 Characteristics of slow release chemical fertilizers
 Different Slow release chemical fertilizers
 Research findings
 Conclusion

4. INTRODUCTION
The steady increase in population growth, food demand and the continuous reduction in
cultivated land per capita induce steady intensification of fertilizer application worldwide.
Nitrogen use efficiency is generally <50% and phosphorus use efficiency 10-30% with
application of urea, single super phosphate etc.
The conventional fertilizer losses dependents most of the processes that nutrients undergo
in soil include transformations induced by microbes (N fixation, nitrification,
denitrification, immobilization etc.), chemical processes (exchange, fixation, precipitation,
hydrolysis, etc.) and physical processes (leaching, runoff, volatilization etc.).
4

5. Cont.....
 The basic concept of slow release chemical fertilizers is that they
release their nutrient contents at more gradual rates that permit
maximum uptake and utilization of the nutrient while minimizing
losses due to leaching, volatilization or excessive growth.
 Slow-release: The release rate of a nutrient from the fertilizers
must be slower than that from a fertilizer in which the nutrient is
readily available for plant uptake.
 Nutrient management through use of slow release chemical
fertilizers of macro and micro nutrients is viable tool in improving
FUE of applied fertilizers through regulated supply/release of
nutrients and synchronizes crop demand.
5

6. Fig.-1. Decomposition model of the coating polymer of
slow-release fertilizer
6

7. Fig.- 2. Mode of action of a coated/encapsulated fertilizers (Basacote®) (Source: Hähndel, 1997, BASF).
7

8. Why need slow release chemical fertilizers ?
8
 Reduced toxicity
Reduce possible losses of nutrients- slower leaching
and run off, evaporation losses of ammonia.
Decreases risk of environmental pollution
Reduction in relevant gas emission.
Slower release rate – plants are able to take up most of
the fertilizers
Reduce labour capital- less frequent application is
required
Lower salt index

9. Cont.....
9

10. Characteristics of slow release chemical fertilizers
 Slowly water soluble
 Low salt
 A single application should supply enough nutrient throughout the
entire growing season
 A maximum percentage recovery
 Not susceptible to environmental loss
 Lasts several weeks to several months
 Formulation allows fertilizer to slowly dissolve or release into the soil
solution surrounding roots
 Nutrient release is dependent on microbial decomposition or physical
and/or chemical processes in combination with microbial activity.
10

11. Fig.- 3 The ‘ideal fertilizer’: the nutrient release is synchronized with
the crop’s nutrient requirements (Source: Lammel, 2005).
11

12. Slow release chemical fertilizers
Slow release chemical fertilizers are available in
market viz:
Slow release N-fertilizers
Slow release P-fertilizers
Slow release K-fertilizers
Polymer-coated multi-nutrient fertilizers
Slow release micronutrient fertilizers
12

13. Slow release N-fertilizers
 Organic-N low-solubility compounds. These can be further divided into
biologically decomposing compounds such as urea-formaldehyde, and
chemically decomposing compounds, such as IBDU (Isobutylidene Diurea).
 Fertilizers N product with a physical barrier that coated fertilizers. The
fertilizer N coatings include organic polymer, resins, and inorganic materials
like sulpher.
 Inorganic low-solubility compounds. Fertilizers such as metal ammonium
phosphates (e.g. magnesium ammonium phosphate and partially acidulated
phosphate rock.
 Nitrification and Urease inhibitor: Nitrapyrin.
13

14. Fig.- 4. Water soluble, N low-solubility and N product with a
coated.
14

15. Organic-N Low-Solubility Compounds
 It reduce the rate of N released to soil solution compared to urea
or other inorganic N sources.
 By slowly dissolving during the growing season.
 NO3- will not exceed crop utilization rate, thereby reducing
potential N losses predominately through leaching.
 But reduced denitrification and volatilization losses are also
possible.
15

16. Table: 1. Common Organic-N Low-solubility Compounds
N-Source Base Compound Common Names N Content
(%)
Inhibition
Duration
(Weeks)
Urea
Formaldehyde
Ureaforms,
Methylol urea,
and Methylene
urea
Nitamin,
Nitroform, UF,
Folocorn,
35-40 6-10
Isobutylidene
Diurea
Isobutylidine urea IBDU 31 10-16
Triazone Triazone/ Urea N-Sure 28-33 6-10
Melamine 2,4,6-triamino-
1,3,5-triazine
Nitrazine 50-60 6-12
Crotonylidene
Diurea
Urea/
Crotonaldehyde
Crotodur,
Triabon, CDU
34 6-12
16
Source –Tisdle et al.(2014)

17. Fertilizers N product with a physical barrier
that coated fertilizer
 Coated Fertilizers- These are slightly soluble in soil solution,
where the N release rate depends on microbial activity and
hydrolysis.
 These products are commonly used in turf, vegetable, and
ornamental systems; however, they are increasingly used in cereal
grain systems.
 Polymer-coated fertilizers are the most recent technology for
controlling N release and reducing N losses by leaching,
denitrification, and volatilization.
17

18. Cont…..
 Only about 30% of granules are perfectly coated, whereas the
coating of remaining granules is thin and/or cracked, which
accelerates dissolution of the urea granule and N release.
 If the S coating is too thick, then N release is slowed or "locked-off
(no N release).
 Therefore, the initial rapid N release could occur too early for
recovery by the target plant, and a portion not released or released
after the N is needed by the plant.
 Coating degradation rate will increase with soil temperature and
moisture.
19

19. Fig.-5 Polymer- Sulfur-coated urea (PSCU)
19

20. Table: 2 Common Coated Fertilizers
N-Source Base
Compound
Common Name N Content
(%)
Inhibition
Duration
(Weeks)
Neem coated
urea
Urea NCU,
NICU (Nimin-
coated urea
- -
Polymer-
Sulfur-coated
urea
Urea Polyplus,
Poly-S
38-42 6-16
Sulfur-coated
urea
Urea Enspan,
SCU
30-42 4-12
Polymer-resin
coated urea
(PSCU)
Urea Polyon,
Meister,
Nutrisphere,
Escote
38-44 8-14
20
Source –Tisdle et al.(2014)

21. Nitrification Inhibitors (NIs)
21
Nitrification Inhibitors:- Adding NIs to fertilizer or manure reduces N03-
formation, maintaining more of the applied N as NH4+ , thus, reducing N
leaching potential. A substance that inhibits the biological oxidation of
ammoniacal-N to nitrate-N.
 NIs also reduce potential denitrification of applied N by reducing the
amount of N03- available for denitrification.
 Nitrapyrin and dicyandiamide are the most common NIs that reduce N
losses when conditions are suitable for rapid nitrification to N03-.

22. Table: 3 Common Nitrification Inhibitors
N-Source Base Compound Common
Names
N
Content
(%)
N Process Inhibition
Duration
(Weeks)
Nitrapyrin 2-chloro-6-
trichloromethyl
pyridine
N-Serve,
Stay-N
2000
- Nitrification
denitrification
2-6
DCD dicyandiamide DCD,
Ensan
1.6 - 4-8
DMPP 3,4-
dimethypyrazole
phosphate
.
DMPP,
Entec
12-26 - 6-8
22Source –Tisdle et al.(2014)

23. Urease Inhibitors
 Urease Inhibitors: Inhibition of urea hydrolysis occurs by
reducing the enzymatic activity of urease, reducing the rate of
urea conversion to NH4+ .
 Nickel (Ni) is important for urease activity and new urease
inhibitor products may inhibit urease by adsorbing Ni on the
CEC of the polymer coating the urea granule.
 NBPT (n-butyl-thio phosphoric triamide) is the most common
urease inhibitor and can be used with any N source or method of
application.
 These products are more effective in reducing N loss under
conditions of high volatilization potential, especially where urea
is surface applied in heavy residue environments.
23

24. Table: 4 Common Urease Inhibitors
N-Source Base
Compound
Common
Names
N
Content
(%)
N Process Inhibition
Duration
(Weeks)
Thiosulphate Ammonium or
calcium
thiosulphate
ATS
CaTS
12 Volatilizatio
n,
nitrification
2-3
NBPT n-butyl-thio
phosphoric
triamide
Agrotain,
SuperU
46 Volatilizatio
n
2-3
24
Source –Tisdle et al.(2014)

25. Slow Release Phosphorus Fertilizers
 P fertilizer through the use of polymer coatings may slow the
formation of these compounds increasing the supply of crop-
available P.
 It has long been understood that even under the best conditions
only 20-30% of applied fertilizer P is taken up by the crop during
the first cropping season.
 It is also understood that at high soil pH levels, P is fixed by
calcium (Ca) and magnesium (Mg) and at low soil pH levels
predominately by iron (Fe) and aluminium (Al).
25

26. 26
 Thus, the historical problem with the soil chemistry of
residual P not taken up by the crop (70-80%).
 It remaining on or near the soil surface has a possible
environmental impact (Eutrophication) through the
combined effects of soil erosion and higher P
concentrations in run-off water and P fertilizers has been
lack of availability
CONT……

27. Malefic Itaconic Copolymer (Avail®)
27
 Specialty fertilizer products has developed and high charge
density dicarboxylic copolymers that affect the availability
and plant utilization of applied P fertilizers.
 These compounds are biodegradable and highly water-
soluble.
 The technology (Avail®) can be applied directly to granular
P fertilizers as a coating or mixed into liquid fertilizers.
 Malefic Itaconic Copolymer (Avail®) is reported to work by
sequestering antagonistic ions that react with P in the soil
solution.


28. Cont…..
28
The high charge density of the additive adsorbs or
“binds” the soil Ca and Mg, Fe and Al acting to reduce
their availability for reaction product formation with
applied fertilizer P forms, thus reducing precipitation and
keeping the P in an available form for longer.

29. Slow Release Potassium Fertilizers
 Potassium is abundant in the earth’s surface.
 90 % K in soils is in the fixed, 1-10 % non-exchangeable form.
 Only 0.1-1 % is in the soil solution or on exchangeable sites.
 In sandy soils, potassium is readily leached.
 It can move rapidly out of the root zone and become unavailable to the plants.
30

30. Cont….
Slow-release potassium sources reduce the potential for
conversion to non-exchangeable forms and minimize
the rate of leaching and fixation of the available
potassium.
This can be achieved by using different types of
coatings, like plaster of paris, wax etc on the
potassium chloride or muriate of potash.
The polymer used is Polyacrylamide which is also
useful in reducing soil erosion.
31

31. Polymer-Coated Multi-nutrient Fertilizers
 Compared to the previous categories that only supply nitrogen,
PCRFs (Polymer-Coated Release Fertilizers) supply all 3 “fertilizer
elements” (nitrogen [N], phosphorus [P], and potassium [K]), and
many formulations include calcium, magnesium, sulphur, and
micronutrients.
 The defining characteristic of PCRFs, however, is the sophisticated
polymer coatings that gradually release nutrients over extended
periods.
 Release rates can be as short as 3 months or as long as 18 months.
 Nutrient release from PCRFs prills occurs by diffusion . 32

32. Cont…
The process occurs in 2 stages.
 First, when prills are exposed to moisture in the soil or
growing medium, water vapour infiltrates into the prills and
condenses on the soluble fertilizer salts, creating an increase
in osmotic pressure.
 Second, this elevated pressure within the prills causes the
fertilizer ions to diffuse outward into the surrounding
medium.
 Some example:- Osmocote®, Multicote® and Nutricote®
are available in many grade.
33

33. Slow Release Micronutrient fertilizers
33
Micronutrients are essential components of proteins and
enzymes and are vital for increasing crop yields as well as
improving the nutritional quality of food.
The bulk of micronutrients used all over the world today are
water soluble salts that include mainly the sulphates or their
chelated forms [Diethylene triamine penta acetic acid (DTPA),
EDTA (Ethylene diamine tetra acetic acid) etc.].

34. Cont….
34
 The focus of research on slow-release fertilizers has been
on the macronutrients (NPK).
 Here slow-release functionality has been achieved by
encapsulation of water soluble materials within a
membrane or conversion to polymers of the urea
aldehydes.
 For micronutrients, the insoluble oxides and phosphate
glasses and amino acids are also used .
 A glassy phosphate produced by fusing oxides of
micronutrients in phosphoric acid at 8000C.

35. Cont….
35
Slow-release compositions are characterized by nutrient
release mechanism that is based on either (i) diffusion
through a membrane/coating or (ii) slow hydrolysis.
Metaphosphates and glassy phosphates dissolve by slow
hydrolysis to release nutrient into the soil.
Nutrient release by diffusion or hydrolysis is dependent on
soil parameters like water content, pH, ionic content,
temperature

36. Cont….
36
 Insoluble compounds can be effective fertilizers only if rates of
release of nutrient ions can match plant requirements throughout
the growth period.
 The slow-release fertilizer in this study has been developed with a
different mechanism of nutrient release.
 Here, plant roots are able to “digest” certain insoluble compounds
by ion-exchange with the root hairs or by extracellular organic
acid secretions that extract nutrients by chelation.
 These compounds have low water solubility and high solubility in
citrate and diethylene triamine penta acetic acid (DTPA).

37. 37
Research findings
Research findings

38. Table 5. Effect of Nutrisphere-N (NSN) addition to urea on ear leaf N
and corn yield at Kansas
N Rate
lb/A
Ear Leaf N % Corn Yield
bu/A
T1 : Control 1.78 139
T2 : 80 Urea 2.79 167
T3 : 80 Urea + NSN 2.90 184
T4 : 160 Urea 2.90 183
T5 : 160 Urea + NSN 3.07 216
T6 : 240 Urea 2.95 192
T7: 240 Urea + NSN 3.09 215
LSD(0.05) - 6
38
Grant and Dowbenko (2005)
Gordon, Kansas State Univ.
Canada
Soil pH 7.0.

39. Treatment Grain
yield
(kg ha-1)
Straw
yield
(kg ha-
1)
N
uptake
(kg ha-
1)
Grain
N
uptake
(kg ha-
1)
Straw
P uptake
(kg ha-1)
Grain
P uptake
(kg ha-1)
Straw
F1 : ( UB ) 4768 5200 40.86 33.57 10.03 5.63
F2 : (RDF) 4427 4847 39.50 32.52 9.07 5.03
F3 : (UB+ 20% N) 4928 5514 49.21 41.43 11.16 6.31
CD at 5%
223 338 3.7 3.53 0.75 0.44
39
Chaudhari (2013)Clayey soilNAU, Navsari
Table 6: Grain, straw yield and N and P uptake in grain and straw as influenced by different treatments of
fertilizers in rice.
Cont..

40. Cont…..
Treatment Dose
F1: Apply N and P at 60 and 30 kg/ha in the form of pellet at
the time of planting at 8-10 cm deep in alternate row.
F2: Recommended practices (100:30:00 kg NPK ha-1) to apply
N in three split and P at the time of transplanting.
F3: Apply 60% RD of N and full dose of P in the form of
Pellets (Briquettes) at the time of planting at 8-10 cm deep
in alternate row in square + 20% N in the form of urea
broadcasting at panicle initiation stage.
40
Chaudhari (2013)NAU, Navsari Clayey soil

41. Table 7: N and P content in grain and straw as influenced by
different treatment of fertilizer in rice.
Treatment
N content
(%)
P content
(%)
Grain Straw Grain Straw
F1 : ( UB )
0.85
0.64 0.21 0.11
F2 : (RDF)
0.89
0.67 0.20 0.10
F3 : (UB+ 20% N)
0.99
0.75 0.23 0.11
CD at 5%
0.052 0.039 0.013 0.006
41
Chaudhari (2013)Clayey soilNAU, Navsari

42. Table 8. Pusa Neem Emulsion (PNE) as an ecofriendly coating agent for urea
quality and efficiency in rice field
Treatments Grain yield of rice (t ha-1)
T1 :Uncoated urea @ 40 kg N ha-1 5.3
T2 :PNE coated @ 40 kg N ha-1 5.6
T3 :Uncoated urea @ 80 kg N ha-1 5.4
T4 :PNE coated @ 80 kg N ha-1 6.1
T5 :Uncoated urea @ 120 kg N ha-1 6.0
T6 :PNE coated @ 120 kg N ha-1 6.7
T7 :Control (0 N) 4.3
LSD (P=0.05) 0.59
42
Prasad et al. (2001)IARI, Delhi Sandy clay-loam in texture

43. Table 9.Effect of different treatments on nutrient uptake by sugarcane ratoon
N P K N P K
T1 : Control(No fertilizer) 121.59 37.07 137.27 2.40 0.58 2.69
T2:100% NPK RD straight ferti. By
conventional method
214.95 64.96 225.66 2.19 0.66 2.29
T3:100% NPK RD straight ferti. by crow bar
(50:50)
306.76 60.72 339.99 3.21 0.63 3.54
T4 : 100% NPK RD briquette (50:50) 330.00 78.88 366.27 2.96 0.72 3.28
T5:75%NPK RD straight ferti by crow
(50:50)
175.62 51.79 207.95 2.03 0.60 2.40
T6: 75% NPK RD briquette (50:50) 240.63 61.35 292.08 2.27 0.70 2.77
T7:50% NPK RD straight ferti by crow
(50:50)
170.10 41.74 199.88 2.28 0.60 2.66
T8 : 50% NPK RD briquette (50:50) 181.24 45.48 237.81 2.20 0.66 2.88
CD at 5% 20.20 7.03 7.90
43
Treatments Nutrient uptake
(Kg ha-1)
Nutrient utilized
by cane (Kg t-1)
More et al.(2014)CSRS, Padegaon Inceptisol

44. Table10: Effect of broadcast coated DAP Malefic Itaconic Copolymer (Avail®) on corn grain yield at Waseca, MN in 2002.
Treatments
Grain
yield
Bu/A
Whole plant
source
P rate
lb P2O5/A
P
management
Yield lb
DM/ A
Uptake
lb P/A
T1 : None 0 - 136.2 686 1.85
T2 : DAP 25 Broad cast 151.0 562 1.77
T3 : DAP 50 Broad cast 155.2 754 2.17
T4 : Coated DAP 25 Broad cast 171.8 778 2.72
T5 : Coated DAP 50 Broad cast 174.6 834 2.47
LSD (0.10) - - 18.6 134 NS
44
Randall and Vetsch (2002)Waseca, MN Calcareous soils

45. Table 11. Maize response to enhanced P availability from
Malefic Itaconic Copolymer (Avail®)
Treatments Yield t/ha
T1 : Control, No P 8.16
T2 : MAP broadcast 8.28
T3 : MAP + Polymer broadcast 9.47
T4 : MAP banded 8.28
T5 : MAP + Polymer banded 9.85
LSD (0.05) 1.00
45Sanders et al. (2003)USA Acid soil pH 5.9. P2O5 @20 lb/A

46. Table 12: Polymer and P application methods effect on wheat yield
Treatments Yield t/ha
T1 : Control 3.14
T2 : MAP banded 3.68
T3 : MAP + polymer, banded 5.17
T4 : MAP broadcast 3.91
T5 : MAP + polymer, broadcast 4.41
T6 : MAP + seed, broadcast 3.70
T7 : MAP + polymer + seed, broadcast 4.59
LSD (0.05) 0.44
46Sanders et al. (2003)USA Soil pH 7.6. P2O5 @30 lb/A

47. Table 13: Corn responses to enhanced P availability on high soil pH (7.8).
Treatments Dry weight
P g/6 plants
P % P Uptake
mg/6
plants
Grain Yield
bu/A
T1 : Control, No P 14.5 0.306 44 108
T2 : MAP banded 18.8 0.309 58 116
T3 : MAP+polymer banded 19.3 0.328 64 122
LSD (0.10) 2.7 0.016 10 5
47
Sanders et al. (2003)USA Soil pH 7.8. P2O5 @ 20 lb/A

48. Table 14 : Field trial using slow-release micronutrient fertilizers on rice yields,
nutrient uptake, at Baruipur (variety- Jaya )
Treatments Yield
(kg/ha)
Total
Uptake
(gm/ha)
Zn
Total
Uptake
(gm/ha)
Fe
Total
Uptake
(gm/ha)
Mn
Total
Uptake
(gm/ha)
Cu
Control 3242 70.6 246 140 21
S1- Sulphates 3076 70.6 350 158 22
S2- Sulphates 3596 75.6 303 162 26
S3- Sulphates 3748 85.7 341 179 23
P1- Slow-release 4647 105.1 472 236 33
P2- Slow-release 4998 120.8 615 288 33
P3- Slow-release 4383 110.6 492 229 34
CD (5%) 758.3 22.4 215 74.4 Cont ….
48
Calcutta, WB Bandyopadhyay et al. (2014)New alluvium

49. Cont.... Multi micronutrient Slow-Release Fertilizer of Zinc, Iron, Manganese,
and Copper
Treatments Level Dose
C Control; -
S1 Sulphates of Zn, Fe, Mn,
and Cu;
S1 : 1 kg/ha Zn + 0.33 kg/ha Fe +
0.165 kg/ha Mn + 0.083 kg/ha Cu;
S2 Sulphates of Zn, Fe, Mn,
and Cu
S2 : 2 kg/ha Zn + 0.66 kg/ha Fe +
0.33 kg/ha Mn + 0.165 kg/ha Cu;
S3 Sulphates of Zn, Fe, Mn,
and Cu
S3 : 4 kg/ha Zn + 1.33 kg/ha Fe +
0.66 kg/haMn + 0.33 kg/ha Cu.
P1 Slow-release
micronutrients;
P1: 1 kg/ha Zn + 0.33 kg/ha Fe +
0.165 kg/ha Mn + 0.083 kg/ha Cu;
P2 Slow-release
micronutrients;
P2: 2 kg/ha Zn + 0.66 kg/ha Fe +
0.33 kg/ha Mn + 0.165 kg/ha Cu;
P3 Slow-release
micronutrients;
P3: 4 kg/ha Zn + 1.33 kg/ha Fe +
0.66 kg/haMn + 0.33 kg/ha Cu.
49Calcutta, WB Bandyopadhyay et al. (2014)

50. Table 15: Field trial using slow-release micronutrient fertilizers on potato yields,
nutrient uptake, at Nalikul ( variety - Jyoti)
Treatments Yield
(kg/ha)
Total
Uptake
(gm/ha)
Zn
Total
Uptake
(gm/ha) Fe
Total
Uptake
(gm/ha)
Mn
Total
Uptake
(gm/ha)
Cu
Control 9900 217 764 69 91
S1- Sulphates 10700 239 948 107 97
S2- Sulphates 9500 216 915 93 97
S3- Sulphates 11000 277 756 85 103
P1- Slow-release 14075 432 1966 151 163
P2- Slow-release 12550 396 1756 140 148
P3- Slow-release 16025 560 2569 225 198
CD (5%) 3460.0 83.9 479.5 33.3 33.1
50
Calcutta, WB Bandyopadhyay et al. (2014)Old alluvium

51. Table 16: Effect of different treatments on available nutrients by sugarcane ratoon at harvest
N P K
Initial 289.00 27.00 310.00
T1 : Control(No fertilizer) 261.85 21.53 247.20
T2 : 100% NPK RD straight ferti. by conventional method 305.55 27.54 288.19
T3 : 100% NPK RD straight ferti. by crow bar (50:50) 316.65 37.68 302.32
T4 : 100% NPK RD briquette (50:50) 324.85 37.76 332.72
T5 : 75%NPK RD straight ferti by crow (50:50) 313.30 27.46 291.31
T6 : 75% NPK RD briquette (50:50) 320.49 31.43 318.31
T7 : 50% NPK RD straight ferti by crow (50:50) 304.69 20.00 289.80
T8 : 50% NPK RD briquette (50:50) 307.31 21.19 268.26
CD at 5% 13.62 9.69 27.63
51
Treatments Available nutrient (Kg ha-1)
More et al.(2014)CSRS, Padegaon Inceptisol

52. Some disadvantages of SRFs
 Most slow release chemical fertilizer cost considerably more
to manufacture than conventional fertilizers.
 Applying sulfur-coated urea almost always lowers soil pH as
aforementioned. However, this acidification may cause
nutrient disorders such as calcium deficiency or magnesium
deficiency.
 Nutrients are not released as predicted because of low
temperatures, flooded or droughty soil, or poor activity of soil
microbes.
52

53. 53
 Application of slow release chemical fertilizers improves the
yield, quality, nutrient uptake, nutrient availability and
improve FUE as well as minimize nutrients losses in different
crop.
 Application of coated DAP and MAP helps in increase crop
yield and enhancing P availability.
 Application of Malefic Itaconic Copolymer MAP enhancing
crop yield and P availability in calcareous soils.
 The slow release chemical fertilizers technology of macro and
micro nutrients not only has the potential to improve crop
yields and farmer profits but also has positive implications on
possible environmental footprint of fertilizer use.
Conclusion

54. Thank you
For your kind attention
54