Resource Book on Horticulture Nursery Management

3 High 19-26 S3
4 Very high >26 S4
3. Residual Sodium Carbonate (RSC): It is the difference between the combined
concentration of Bicarbonate (HCO3 2- ) and carbonate (CO3) with that of calcium and
Magnesium and expressed in terms of me/liter.
Sr. No. RSC Class SAR range Classes
1 Low 6.0 4
4. Boron: Though boron is an essential plant nutrient it becomes toxic if present in
water beyond a particular level.
Sr. No. Boron Value Boron (ppm)
1 Low 4.0
Relative Salt Tolerance of a Crop
1. Salt Tolerant (CP1) Crops: Barley, Sugar beat, Tobacco, Cotton, Wheat, Sugarcane,
Date palm, Coconut.
2. Salt Semi tolerant(CP2) Crops: Oats, Rice, Jowar, Maize, Bajara, Wheat, Red gram
Castor, Jute, Soybean, Tomato, Cabbage, Cauliflower, Potato, Radish, Carrot, Onion,
Peas, Cucumber, Grapes, Fig, Guava, Mango, Banana, Pomegranate, Orange and
Lemon.
3. Salt Sensitive (CP3) Crops: Green gram, Peach, Pear, Apple, Pineapple.
Management of Poor Quality Water for Irrigation:
1. Dilution with good quality irrigation water.
2. Flooding with good quality water once or twice to flush out salts beyond root zone.
3. Gypsum mixing with water to reduce Sodium salt hazards and also to improve soil
structure.
4. Providing drainage to remove salts.
5. Using poor quality water in sandy soils.
6. Growing salt tolerant crops.
7. Adopting drip irrigation for poor quality water.
<strong>Resource</strong> <strong>Book</strong> on Horticulture Nursery Management : 61