- Genesis from swampy area
- Chinese and India (3000 year old texts from both places mention it)
REQUIREMENTS FOR WET PADDY CULTIVATION
- More than 90 Cm of annual rainfall, notwithstanding evaporation.
- Better if around 200-250cm
- Flooded condition (Water in state of gentle movement, not stagnant otherwise low soil aeration and nitrate formation impeded)
- High light intensity (Abundant sunshine essential during 4 months of growth)
- 20-27 degree C (15 degree for germination)
- One of the very few crops which can sustain excess of heat as long as there is sufficient water
- Can be grown on wide range of soils, provided condition one and two are met.
- Ideal soil: Heavy clayey and loamy soil that is moisture retentive, so that water does not readily percolates through and is acidic in reaction. pH 4-6.5
Flat lands are preferred for easy flooding and irrigation. Therefore, ideal habitats are alluvial delta and flood plains. For E.g.: Ganga, Irrawaddy, Mekong.
Even in highlands, the fields are carefully levelled to create flooding conditions and edges are carefully bounded to retain water and also silt.
High population of hills in Monsoon Asia makes this task widely practiced.
Labour: Traditionally extremely labour intensive. Whole family is involved throughout the year. Mechanization is extensive in developed parts of the world and China.
- Require N, P, K
- Traces of Fe, Mn and B especially in calcareous and sandy salts are very beneficial to paddy plants.
- Tropical, Sub tropical and monsoon climates
- Warm temperate lands of southern Europe and US
- Mainly Irrigated lowlands, flooded plains, Deltas swamp conditions
- Its growing conditions are inhibiting causes for other major food crops, hence it is unique
DIFFICULTY OF FARM MECHANIZATION IN PADDY
- Machines should be robust enough to work in flooded fields.
- Desirability of small flat lands separated by bunds make the movement of tractors tougher.
- Most of the paddy regions of the world are also the most populated regions and hence cheap labor is abundantly available, hindering mechanization.
- China, India, Bangladesh, Japan (Highest Productivity)
- Outside monsoon Asia (Nile Delta)
- Southeast Brazil