1.
Water quality for
cereals and millets
Jenin.R
2021005036
Jerald Edison.G
2021005037
Presented by:

2.
Contents
• Water quality
• Total Soluble Salts
• Sodium Adsorption Ratio(SAR)
• Exchangable Sodium Percentage(ESP)
• Residual Sodium Carbonate(RSC)
• Boron
• chloride
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3.
Water Quality
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• Quality irrigation water is an essential resource for better growth of
plants
• Concentration and composition of dissolved constituents in water
determine its quality for irrigation use
• Irrigation purposes the water quality is assessed on the basis of the chemical
characteristics

4.
Total salt
concentration
The quantities of salt dissolved in
irrigation water are usually
expressed in terms of electrical
conductivity (EC) mg/L (ppm)
or me/L,
Alkalinity / sodicity
hazards
Absolute and relative
concentrations of specific
cations and anions
Presence of toxic ions Boron,fluoride,nitrate,
selenium etc

5.
• If TSS was high in irrigation water it leads to mild chlorosis of the
foliage, later progressing to a necrosis of leaf tips and margins.
• There will be yield loss if the salinity value is higher than the
threshold value
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TSS in irrigation water

6.
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7.
Sodium Adsorption Ratio(SAR)
• Sodium adsorption ratio (SAR) is an important irrigation water
quality parameter.
• It is a measure of the amount of sodium relative to the amount of
calcium and magnesium in a water sample.
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8.
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Crops moderately tolerant to SAR and typically handle SAR values of 20-50
includes:
•Oats
•Rice
Crops tolerant to SAR and typically handle SAR values of 50-100 includes:
•Wheat
•Barley

9.
• ESP measures the proportion of cation exchange sites occupied by
sodium
• Soils are consideres sodic when ESP is above 6.And highly sodic
when the ESP is greater than 15
Exchangable Sodium
Percentage

10.
ESP Range Crops
16 -20 maize
20-25 Pearl-millet
25-30 sorghum
30-50 wheat
60-71 rice

11.
Residual Sodium
Carbonate(RSC)
• The residual sodium carbonate (RSC) index of irrigation water or soil
water is used to indicate the alkalinity hazard for soil.
• When dissolved sodium in comparison with dissolved calcium and
magnesium is high in water, clay soil swells or undergoes dispersion which
drastically reduces its infiltration capacity.
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12.
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RSC value (meL-1) Waterquality
< 1.25 Water can be used safely
1.25 - 2.5 Water can be used with certain
management
> 2.5 Unsuitable for irrigation purposes

13.
Boron
• Apart from the salinity or the sodicity hazard, the constituents of
much irrigation water may cause toxicity problems when taken up
by the plants in excess amounts.
• The toxic constituents of major concern are sodium, chloride and
boron
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14.
Sensitive (0.75 - 1 mg/l)
Wheat Triticum eastivum
Barley Hordeum vulgare
Moderately Tolerant (2-4 mg/l)
Oats Avena sativa
Maize Zea mays
Tolerant (4-6 mg/l)
Sorghum Sorghum bicolor

15.
Chloride
• The chloride ion can be taken up by plant roots and accumulate in
the leaves
• Excessive accumulation may cause burning of the leaf tips or
margins, bronzing and premature yellowing of the leaves.
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16.
Sensitivity Chloride (mg/L) Affected crop
Sensitive <178 Rice
Moderately tolerant 355–710 Barley,Wheat
Tolerant >710 sorghum

17.
Thank you