GLOBAL SCENARIO OF THE PROBLOM
• Soil salinity and sodicity - global
problem, exists in six continents and
nearly 100 countries including
Pakistan.
• Major countries - Argentina, Australia,
Egypt, Iran, Pakistan, USA, Russia,
India, China, Thailand and South
Africa.
Statistical information regarding area
Area
Pakistan
Punjab
(m ha)
Geographical area
80
21
Total cropped area
22
16
Surveyed area
69
21
Irrigated area
18
14
6.68
2.68
Saline and saline-sodic soil
Source: Agricultural statistics of Pakistan 2006
SOIL SALINITY/SODICITY PROBLEM IN PROVINCES OF PAKISTAN
(m ha)
Punjab
2.68
Sind
2.11
Baluchistan
2.31
N.W.F.P.
0.04
Salt-Affected Area (m ha) of Punjab, Pakistan
Year
Area
surveyed
Salt-Affected
Uncult.
Cultiv.
Total
%
1945-46
4.84
0.42
0.49
0.91
18.80
1955-56
5.96
0.05
0.69
1.20
20.64
1965-66
6.88
0.44
0.68
1.12
16.28
1975-76
7.34
0.37
0.61
0.98
13.35
1985-86
7.57
0.30
0.58
0.88
11.62
2000-01
7.92
1.16
1.51
2.67
33.71
Source: Ahmad & Chaudhry, 2004
TUBE WELLS IN THE PUNJAB
No. of tube wells
1200000
1000000
800000
600000
400000
200000
0
1979 or
before
1985 or
before
1986 to
1990
2002-2003 2006-2007
year
Source:
Punjab Development Statistics, 2006
No. of Tubewells in Punjab
1000000
No. of Tubewells
900000
800000
700000
600000
No. of Tubewells
500000
400000
300000
1999-00 2000-01 2001-02 2002-03 2003-04 2004-05 2005-06 2006-07 2007-08 2008-09
Years
Source:
Punjab Development Statistics, 2011
Salinity/sodicity: 6.68 m ha
60 % are saline-sodic in Pakistan,
84 % are saline-sodic in Punjab
(Khan, 1998)
CROPS / PLANTS TOLERANCE WITH RESPECT
TO SALINITY AND SODICITY
Field crops
S.No.
English
name/Common
name
Botanical name
50% reduction in
yield
ECe
ESP
1
Millet
Panicum miliaceum
19.5
20-25
2
Sorghum
Sorghum bicolor
16.0
15-40
3
Sesbania
Sesbenia microcarpa
15.4
50-60
4
Soybean
Glycine max
7.5
16-20
5
Maize
Zea mays
8.6
<15
6
Sunflower
Halianthus annus
6.3
30-50
7
Cotton
Gossypium hirsutum
17.1
30-50
8
Mash
Vigna mungo
10.0
10-15
9
Rice
Oryza sativa
7.4
60-70
S.No. English
name/
Common
name
Botanical name
10
Barley
Hordium vulgare
15.7
50-60
11
Sugar beet
Beta vulgaris
15.0
>40
12
Lentil
Lens culinaris
12.0
10-15
13
Oat
Avena sativa
11.7
30-50
14
Berseem
Trifolium
alexandrium
10.3
20-25
15
Safflower
Cathamus
tinctorium
9.9
10-15
50% reduction in yield
ECe
ESP
S.No.
50% reduction in yield
English
name/
Common
name
Botanical name
16
Wheat
Triticum aestivum
9.9
30-50
17
Sugarcane
Saccharum
officinarum
9.9
15-40
18
Canola
Brassica napus
8.16
30-50
19
Alfalfa
Medicago sativa
8.8
>40
20
Flax
Linum ustiatissimum
5.9
25-30
21
Mustard
Brassica compastis
(CS-52)
Salinity/Sodicity
tolerant
30-50
22
Kharchia-65
Triticum aestivum
Salinity/Sodicity
tolerant
30-50
ECe
ESP
Forages
S.No. English name
/Common
name
Botanical name
1
Kallar grass
Leptochloa
fusca
22.0
>70
2
Sudan grass
Sorghum
sudanense
14.4
-
3
Tall fescue
Festuca elatior
13.3
<15
4
Garden cress
Lepedium
sativum
10.0
-
5
Rhodes grass
Chloris gayana
8.0
>70
6
Australian
grass
Diplachne fusca 22.0
-
7
Fodder beet
Beta vulgaris
<55
50% reduction in yield
ECe
19.0
ESP
S.N
o.
English
name
/Common
name
Botanical name
8
Guar
Cyamopsis
tetragonoloba
Salinity/Sodi
city tolerant
25-30
9
Tall wheat
grass
Agropyron
elongatum
19.4
>40
10
Bermuda
grass
Cynodon dactylon
14.7
70
11
Triticale
Secole cereale X
Triticum durum
13.5
-
12
Wild rye
Elymus triticoides
11.0
5-15
13
Mott grass
Pennisetum
purporium
14
Para Grass
Brachiaria mutica
11.0
60-70
50% reduction in yield
ECe
ESP
Vegetables
S. English
Botanical name
No name/Com
.
mon name
50% reduction in yield
1
Asparagus
13.0
5-15
2
Cantaloupe Cucumis melo
9.1
5-15
3
Pumpkin
Cucurbita pepo
7.9
5-15
4
Okra
Abelmoschus
esculentus
Salinity tolerant
-
5
Bringal
Solanum
melongena
Salinity tolerant
-
6
Cauliflower Brassica oleracea 10.1
5-15
7
Broccoli
5-15
Asparagus
officinnalis
Brassica
oleraceaitalica
ECe
8.2
ESP
S.No.
English
name/Co
mmon
name
Botanical name
8
Spinach
Spinacia
oleracea
8.6
15-40
9
Tomato
Lycopersicum
esculentum
7.6
30-50
10
Cabbage
Brassica
oleracea
7.0
5-15
11
Onion
Allium cepa
4.3
20-25
12
Coriander
Coriandrum
sativum
Salinity tolerant
5-15
13
Garlic
Allium sativum
Salinity tolerant
25-30
50% reduction in yield
ECe
ESP
Medicinal plants
S.No.
English
name/Common
name
Botanical name
50% reduction in
yield
1
Hina
Lasonia spp.
Salinity tolerant
2
Sweet basil
Ocimum
basilicum
Salinity tolerant
3
Parslane
Portulaca
oleracea
Salinity tolerant
4
Mint
Mentha veridis
Salinity tolerant
5
Liquorice
Glycerrhiza
glabra
Salinity tolerant
6
Fenugreek
Tigonella
foenumgraceum
Salinity tolerant
NUTRITIONAL ASPECTS OF SALT AFFECTED SOILS
Availability of plant nutrients is affected adversely in salt affected soils and
their productivity is decreased resultantly.
The main reasons for depletion in fertility of such soils are as under:1. Excess of certain ions like Na, CO3 and HCO3 suppress the availability
of other like Ca, K, P, Zn, Mn, Fe and B. technically, it is called
antagonistic effect.
2. An increase in soil pH, especially in sodic soils decreases the overall
availability of phosphorus and micronutrients.
3. In salt affected soils microbiological activity is curtailed to a great
extent.
4. During the reclamation process, leaching of salts is also accompanied
by leaching of nutrients.
5. Nutrient uptake by plants in salt affected soils is also reduced due to
decreased water uptake because of physiological unavailability of the
latter.
NITROGEN
Nitrogenous fertilizer play important role in utilizing the salt affected soils
for improving crop yield because
1. These soils are deficient in nitrogen.
2. Low N and organic matter contents
3. Reduced microbial population
4. Rate of mineralization of nitrogen is slow down. Salinity level (ECe)
above 10 dS m-1 is harmful
5. Nitrogen absorption by plants increase up to moderate salinity value (6
dS m-1) and then decreases at higher salinity values and ESP of soil.
6. The rate of conversion of one form of nitrogen to other forms is quite
slow e.g. hydrolysis of urea to ammonium N was much slow down with
increase in soil pH.
7. Low enzymatic activity in saline soils.
8. Chloride reduces the rate of nitrification when present
between 0.5- 1.0 percent.
9. Ammonium volatilization loss from applied nitrogen
increases with increase in pH/alkalinity of soil
10. 20-25 percent over dose of nitrogen fertilizers
PHOSPHORUS
Chemistry of phosphorus is more complex in salt affected as compared to
normal soils.
1. The availability of P is decreased in sodic soil during reclamation.
2. The availability of P in saline soil may decrease, increase or remain
unchanged depending on the nature and degree of salinity.
3. Salts which change pH show more changes in the solubility of
phosphates in soils.
4. Barren sodic soils have high amounts of Olsen extractable P and
categorized as adequate in available P.
5. Amount of water soluble P increase with soil pH above 9.0.
6. The availability of phosphorus increases up to moderate salinity (ECe 6
dS m-1)
7. In sodic soils, there is a tendency for increase of Ca-P form
with increase in ESP and decrease in Al-P
8. In highly saline sodic soils about 10-15 percent more P is to
be added and special care is to be taken for calcareous
soils.
9.Phosphorus absorption by plants is generally reduced with
increase in salinity and ESP of soil.
10. P uptake by plants increases up to moderate salinity (ECe 6
dS m-1) and ESP (30-35) levels.
Potassium
1. Increase in soil salinity depresses the K uptake by plant while Na
uptake increases.
2. In sodic soil Na increases and those of Ca, Mg and K decreases.
MICRONUTRIENTS
High pH, high CaCO3, high ESP, low organic matter content and high
amount of soluble salts are the major factors responsible for
micronutrients deficiencies in salt affected soils.
Among the micronutrients, Zn deficiency is wide spread in sodic soils.
Other micronutrients like Fe, Mn and Cu are also precipitated as their
hydroxides or carbonates in highly alkaline range and may show their
deficiency.
In many areas particularly under poorly drained condition in medium
and fine textured soil B has been reported to be present in toxic
amounts.
Low nutrient use efficiency
Nutrient
Efficiency Cause of low efficiency
(%)
Nitrogen
30-50
Immobilization, volatilization,
denitrification, Leaching
Phosphorus
15-20
Potassium
Sulphur
70-80
8-10
Fixation in soils Al – P, Fe – P,
Ca – P
Fixation in clay - lattices
Micro
nutrients
(Zn, Fe, Cu,
Mn, B)
1-2
Immobilization, Leaching with
water
Fixation in soils
Field experiments Results
RESPONSE OF RICE LINE PB-95 TO
DIFFERENT NPK LEVELS
Original soil analyses
pHs
8.60
ECe (dS m-1)
4.72
SAR (mmol L-1)1/2
26.28
O.M. (%)
0.42
Available P (mg kg-1)
5.18
Extractable K (mg kg-1)
86.0
Effect of different NPK rates on rice yield (t ha-1)
NPK (kg ha-1)
Paddy yield
Straw yield
1.02 F
1.16 F
T1
0-0-0
T2
0-75-75
2.41 DE
2.74 DE
T3
60-75-75
2.54 D
2.88 D
T4
120-75-75
3.52 AB
4.00 AB
T5
180-75-75
3.41 B
3.88 B
T6
120-0-75
2.35 E
2.67 E
T7
120-50-75
3.12 C
3.55 C
T8
120-100-75
3.63 A
4.13 A
T9
120-75-0
3.41 B
3.88 B
T10
120-75-50
3.55 AB
4.04 AB
T11
120-75-100
3.52 AB
4.00 AB
0.1714
0.2041
LSD
Nutrients Use Efficiency (%)
Treatments
NPK (kg ha-1)
N-Use Efficiency
P-Use Efficiency
K-Use Efficiency
T1
0-0-0
0.00 F
0.00 D
0.00 H
T2
0-75-75
0.00 F
7.88 BC
26.99 G
T3
60-75-75
38.99 A
9.75 B
33.65 F
T4
120-75-75
38.20 A
15.88 A
57.38 C
T5
180-75-75
27.27 D
15.72 A
54.89 C
T6
120-0-75
17.77 E
0.00 D
32.30 F
T7
120-50-75
28.93 D
5.72 C
49.82 D
T8
120-100-75
38.24 A
15.08 A
62.47 B
T9
120-75-0
32.88 C
14.93 A
0.00 H
T10
120-75-50
35.71 BC
16.41 A
70.66 A
T11
120-75-100
35.81 ABC
17.01 A
43.50 E
3.2008
2.1755
3.8113
LSD
NPK concentration in Paddy
Treatments
NPK (kg ha-1)
N-Concentration
(%)
P- Concentration
(%)
K- Concentration
(%)
T1
0-0-0
1.04 F
0.13 D
0.11 F
T2
0-75-75
1.07 EF
0.26 BC
0.21 E
T3
60-75-75
1.13 DE
0.27 BC
0.27 CD
T4
120-75-75
1.28 AB
0.28 B
0.29 BC
T5
180-75-75
1.35 A
0.28 B
0.30 BC
T6
120-0-75
1.14 DE
0.15 D
0.25 D
T7
120-50-75
1.18 CD
0.26 BC
0.29 BC
T8
120-100-75
1.25 BC
0.34 A
0.32 AB
T9
120-75-0
1.19 CD
0.27 BC
0.12 F
T10
120-75-50
1.21BC
0.29 B
0.21 E
T11
120-75-100
1.22 BC
0.30 A
0.35 A
0.0720
0.0546
0.0348
LSD
NPK concentration in rice straw
Treatments
NPK (kg ha-1)
N-Concentration
(%)
P- Concentration
(%)
K- Concentration
(%)
T1
0-0-0
0.31 E
0.09 E
0.79 E
T2
0-75-75
0.32 E
0.11 DE
1.05 D
T3
60-75-75
0.44 D
0.14 BC
1.14 C
T4
120-75-75
0.56 B
0.16 AB
1.25 AB
T5
180-75-75
0.65 A
0.17 A
1.24 B
T6
120-0-75
0.46 CD
0.10 DE
1.22 B
T7
120-50-75
0.50 BCD
0.12 CD
1.26 AB
T8
120-100-75
0.54 B
0.18 A
1.29 A
T9
120-75-0
0.50 BC
0.16 AB
0.74 E
T10
120-75-50
0.52 BC
0.16 AB
1.09 CD
T11
120-75-100
0.53 B
0.17 A
1.21 B
0.003
0.0294
0.0523
LSD
RESPONSE OF WHEAT TO POTASSIUM
APPLICATION IN SALT AFFECTED SOILS.
Treatments:
T1: 140-110-0 kg NPK ha-1
T2: 140-110-30 kg NPK ha-1
T3: 140-110-60 kg NPK ha-1
T4: 140-110-90 kg NPK ha-1
T5: 140-110-120 kg NPK ha-1
Pre-sowing Soil Analysis:
ECe:
pHs:
SAR:
OM:
Avail. P:
Ex. K:
5.28 d Sm-1
8.57
29.80
0.36%
5.32 mg kg-1
114 mg kg-1
Treatments
NPK kg ha-1
140-110-0
Grain Yield
(t ha-1)
2.54 b
140-110-30
2.88 c
3.55 c
36.17 a
140-110-60
3.19 b
3.98 b
34.57 a
140-110-90
3.31 a
4.29 a
29.30 b
140-110-120
3.28 a
4.24 a
20.87 b
0.08
0.093
7.43
LSD
Straw yield
K-use
Efficiency
(t ha-1)
3.06 d
0.0 c
RESPONSE OF RICE TO POTASSIUM
APPLICATION IN SALT AFFECTED
SOILS.
Treatments:
T1: 110-90-0 kg NPK ha-1
T2: 110-90-25 kg NPK ha-1
T3: 110-90-50 kg NPK ha-1
T4: 110-90-75 kg NPK ha-1
T5: 110-90-100 kg NPK ha-1
Pre-sowing Soil Analysis:
ECe:
pHs:
SAR:
OM:
Avail. P:
Ex. K:
6.10 d Sm-1
8.75
37.56
0.28%
5.90 mg kg-1
110 mg kg-1
Treatments
(NPK kg ha-1)
110-90-0
Paddy Yield
(t ha-1)
2.46 c
Straw yield
K-use
Efficiency
(t ha-1)
2.95 d
0.0 c
110-90-25
2.61bc
3.13 c
19.61 b
110-90-50
2.86 b
3.43 b
24.97 a
110-90-75
3.17 a
3.80 a
25.36 a
110-90-100
3.22 a
3.86 a
20.87 b
LSD
0.255
0.1593
4.510
RESPONSE OF WHEAT TO BORON APPLICATION IN
SALT AFFECTED SOIL
PRE-SOWING SOIL ANALYSIS
ECe (dS m-1)
4.74-4.90
pHs
8.60-8.72
SAR(m mol L-1)1/2
24.98-28.66
O.M.(%)
0.65
Available P ( mg kg-1)
8.30
Extractable K (mg kg-1)
115.0
Available B ( mg kg-1)
0.306
Effect of different rates of boron on grain and straw yield of wheat
Treatments
Grain yield
( t. ha-1)
Straw yield
(t. ha-1)
T1 140-110-60 kg ha-1
3.21 E
3.32 E
T2 140-110-60 kg ha-1 +B @ 0.25 kg ha-1
3.36 D
3.41 DE
T3 140-110-60 kg ha-1 +B @ 0.50 kg ha-1
3.44 CD
3.52 CD
T4 140-110-60 kg ha-1 +B @ 1.00 kg ha-1
3.74 A
3.88 A
T5 140-110-60 kg ha-1 +B @ 1.50 kg ha-1
3.62 AB
3.69 B
T6 140-110-60 kg ha-1 +B @ 2.00 kg ha-1
3.57 BC
3.63 BC
LSD
0.1409
0.1522
Treatments
Boron conc.
in grain
(mgkg-1)
Boron conc.
in straw
(mgkg-1)
Boron Use
Efficiency
(%)
T1 140-110-60 kg ha-1
1.24 C
1.54 C
0.00
T2 140-110-60 kg ha-1+B @ 0.25 kg ha-1
1.24 C
1.56 BC
1.39 AB
T3 140-110-60 kg ha-1+B @ 0.50 kg ha-1
1.28 BC
1.59 ABC
1.59 AB
T4 140-110-60 kg ha-1+B @ 1.00 kg ha-1
1.30 ABC
1.62 ABC
1.82 A
T5 140-110-60 kg ha-1+B @ 1.50 kg ha-1
1.34 AB
1.67 AB
1.13 AB
T6 140-110-60 kg ha-1+B @ 2.00 kg ha-1
1.36 A
1.70 A
0.86 B
LSD
0.0630
0.1165
0.8307
Post Harvest soil analysis
Treatments
pHs
ECe
(dS m-1)
SAR
(m mol L-1)1/2
Available B
(mg kg-1)
T1 140-110-60 kg
ha-1
8.65
4.83
25.77
0.288
T2 140-110-60+B @
0.25 kg ha-1
8.64
4.76
23.10
0.314
T3 140-110-60+B @
0.50 kg ha-1
8.62
4.74
22.65
0.351
T4 140-110-60+B @
1.00 kg ha-1
8.60
4.72
22.54
0.483
T5 140-110-60+B @
1.50 kg ha-1
8.60
4.71
22.57
0.634
T6 140-110-60+B @
2.0 kg ha-1
8.61
4.72
22.69
0.766
THANKS