krishigyan Published: 3 years ago



Fertility, manure and fertilizers of Soil:

  • Soil tilth:- Optimum physical condition of soil for crop growth.
  • 16 important element for plant growth and are divided into Macro and Micro nutrient.
  • L,Se,Ga,Al are beneficial elements
  • Al and Sl are Ballast elements.
  • Functional or metabolic nutrient term is given by Nicholas.
  • Essentially of nutrient is given by Arnon
  • Nitrate, Chloride and Sulphate remain in soil solution and are not absorbed by soil colloids.
  • Diffusion enables nutrient movement without the movement of water.
  • Role of Nitrogen:
    1. P & K utilization
    2. causes greenish colour, deficiency cause yellowing colour of leaves
    3. available in both anionic and cationic form
  • Role of Phosphorus:
    1. helps in root growth
    2. grain formation and maturation of crops
    3. new cell formation
    4. improves quality of crop
    5. increase resistance to disease.
    6. Deficiency cause: discoloration of stem and foliage
  • Role of Potassium:
    1. helps in resistance of pest and diseases
    2. improving the quality of tobacco and citrus.
    3. sugar and starch production
  • 1st nitrogenous fertilizer- Sodium Nitrate
  • Urea super granules urea formaldehyde,neem coated urea etc -Sow release N fertilizer
  • Highest Nitrogen-82% in Anhydrous Ammonia
  • Chilean Nitrate are useful in acid soil and are 16% in nitrate form.
  • 33-35% N in Ammonium nitrate
  • 26% N in Ammonium chloride – these are not recommended for tobacco, tomatoes and other such crops.
  • 10-12% N in Dried bone meal
  • 46% N in Urea.

Conservation measures of Soil and water:

  • Intensity of hazards and limitations are depends upon Class of soil
  • Class V
    1. no crosion hazarzard
    2. difficult to remove its limitatons
  • Class VIII
    1. deserts, rivers washes, mine spoils and other barren lands.

Complex Fertilizers

  • Diammonium Phosphate:(DAP):- 18:46:0

Potassic Fertilizers:

  • K fertilizers are generally imported from Germany and France in India.
  • SOP:- K2SO4, 48-52% K2O.
  • MOP: KCl 50-63% K2O


  • FYM has 0.15% of P2O5, 0.3% of N andK2O.
  • Poudrette is also called Night soil.
  • 2.95 kg of N can be obtained from 1 tonne of cow dung,2.95 kg of potash and 1.59 kg of phosphoric acid.

Phosphatic fertilizers:

  • Most widely used water-soluble  P fertilizer in India:- Super Phosphate

Soil Testing:

  • Soil test report have- pH, available NPK, Gypsum, Soil texture, EC, OC,and lime amount to be added, Green Manure/Compost in the flooding and training.
  • Ph :
    1. Below 6:- acidic
    2. 6-8.5:- neutral
    3. 8.6-9:- tending to be saline
    4. above 9:- alkaline
  • value of EC in dS/m (Total soluble salt)
    1. below 1:- normal
    2. 1-2:- critical for germination
    3. 2-4:- critical for growth
    4. above 4:- injurious to crops

Erosion and Conservation of Soil:

  • 187.9Mha geographical area is affected by soil degradation.

Soil loss affecting factor:

  • lateritic soils are less erodible than black soils
  • 22m long and 9% slope is the ideal plot to calculate soil loss
  • Order of soil loss
    1. Cultivated fallow land>bare fallow>Maize-wheat under up and down cultivation> Natural grasses
    2. Cultivated fallow>jowar>natural cover
    3. overgrazed fallow or maize>natural fallow

Size of Gullies:-

SymbolDescriptionSpecificationG1Very smallDeep:-3m,bed width:- 18mG2SmallDeep:-3m, bed width>18mG3MediumDeep:-3-9m, bed width>18m, slope:-8-15%G4Deep & Narrow

  1. Deep:- 3-9 m, bed width<18m
  2. Deep>9m


Wind erosion:

  • Generally occurs in arid and semi-arid regions
  • Saltation, suspension and surface creep- are 3typees of soil movement
  • Saltation is important – in this particles of 0.1-0.5mm is lifted
  • Suspension:- <0.1mm(dia) particles are lifted
  • Surface creep:- 0.5-1mm particles are lifted.

Agronomic measure:

  • Soil loss:- Urad>Maize>Gora paddy>Ground nut