Green manuring


Published on

Published in: Technology
  • Be the first to comment

No Downloads
Total views
On SlideShare
From Embeds
Number of Embeds
Embeds 0
No embeds

No notes for slide

Green manuring

  1. 1. Muhammad Usman 2012-ag-2995
  2. 2.  A growing crop, such as clover or grass, that is plowed under the soil to improve fertility
  3. 3.   Nitrogen and phosphorus are deficient in Pakistani soils and there is hardly any soil from which high yields can be obtained without any fertilization.
  4. 4.  The production of high inorganic fertilizers requires energy and it is estimated that fertilizer production accounts for about 45% of the energy; used in agriculture worldwide; 73% of which is used for the manufacture of N fertilize.
  5. 5.  The current energy crisis in the world has enhanced the prices of mineral fertilizers. So it has revived the interests in the use of green manures. The rising interest had led to the identification of some legumes that have high green manuring potential
  6. 6.  1. Green manuring in-situ:  When green manure crops are grown in the field itself either as a pure crop or as intercrop with the main crop and buried in the same field, it is known as Green manuring In-situ. E.g.: Sunhemp, Dhancha, Urd, Mung, Cowpea, Berseem, Senji, etc.
  7. 7.  2. Green leaf manuring: It refers to turning into the soil green leaves and tender green twigs collected from shrubs and tress grown on bunds, waste lands and nearby forest area. E.g.: Glyricidia, wild Dhancha, Karanj.
  8. 8.  Legumes  cowpeas  Soybeans  sweet clover  Vetch  Millet  sorghum
  9. 9.  Berseem  Janter  Guara  Sunhemp  Senji
  10. 10.  1. Pakistani Janter (Sebania aculeata)  2. Tropical Janter (Sesbania rostrata}  3. Guara (Cymopsis tetragonolobas}  4. Sunnhemp (Crotolaria juncea)  5. Mungbean (Vigna radiata)  6. Cowpeas (Vigna unguiculata]
  11. 11.  These crops are sown as:  i) Main crop,  ii) Inter row sown crop,  iii) On bare fallow, depending upon the soil and climatic conditions of the region.
  12. 12.  Short Period  Yield a large quantity of green material within a short period.  Quick Growing  Be quick growing especially in the beginning, so as to suppress weeds.  More Leafy Growth  Be succulent and have more leafy growth than woody growth, so that its decomposition will be rapid.
  13. 13.  Nitrogen Fixation  Preferably is a legume, so that atm. ‘N’ will be fixed.  Root System  Have deep and fibrous root system so that it will absorb nutrients from lower zone and add them to the surface soil and also improve soil structure.  Grow In Poor Soil  Be able to grow even on poor soils.
  14. 14.  A green manuring crop may be turned in at the flowering stage or just before the flowering. The majority of the G.M. crops require 6 to 8 weeks after sowing at which there is maximum green matter production and most succulent
  15. 15.  When the crop reach full bloom than With the help of sohaga fall all the green manure crop in the field,Then mix the crop with the help of rotavator and disc harrow and give irrigation to start the process of decomposition
  16. 16.  Improve soil Structure  Has positive influence on the physical and chemical properties of soil.  Organic Matter  Helps to maintain the organic matter status of soil.  Source of Food and Energy  Serves as source of food and energy for the microbes multiplies rapidly, not only decompose the GM and result in release of plant nutrients in available forms for use by the crops.  .
  17. 17.  Improve Soil Aeration  Improves aeration in soils by stimulating activities of surface film of algae and bacteria  Water Holding Capacity  It improve water holding capacity of poor soil.
  18. 18.  Green manuring builds up soil structure and improves tilth  Promotes formation of crumbs in heavy soils leading to aeration and drainage  Increases the water holding capacity of light soils.  Form a canopy cover over the soil, reduce the soil temperature and prevents from erosive action of rain and water
  19. 19.  Absorb nutrients from the lower layer and leave them in surface when ploughed  Prevent leaching of nutrients to lower layers.  Harbour N fixing bacteria, rhizobia in root nodules and fix atmospheric N  (60 to 100 kg N/ha)  Increase the solubility of lime phosphates, trace elements etc., through the activity of the soil microorganisms and by producing organic acids during decomposition.
  20. 20.  Sesbania aculeata (daincha) applied to sodic soils continuously for four or five seasons improves the permeability and helps to reclaim.  Tamarindus indica has a buffering effect when applied to sodic soils.
  21. 21.  Increases the yield of crops to 15 to 20 %  Vitamin and protein content of crop increased  It also control the pests.
  22. 22.  i) Under rain fed conditions, the germination and growth of succeeding crop may be affected due to depletion of moisture for the growth and decomposition of G.M.  ii) G.M. crop inclusive of decomposition period occupies the field least 75-80 days which means a loss of one crop.  iii) Incidence of pests and diseases may increases if the G.M. is not kept free from them.