IRRIGATION

Irrigation is the the controlled application of water for agricultural purposes through man made systems to supply water requirements not satisfied by rainfall. Crop irrigation is vital throughout the world in order to provide the world's ever-growing populations with enough food. Irrigation is the act of artificially applying water to soil to allow plant growth. This can also include applying water to a lawn or garden. The term usually refers to providing large amounts of water in arid or dry regions to grow crops. The world's rapid population growth has produced more of a need for irrigation. With it, a higher crop yield is possible on older lands.

Although irrigation is most commonly used in areas with up to 20 inches (500 mm) of rainfall annually, sometimes it also is practiced in areas where the annual rainfall is 20 to 40 inches (500 to 1,000 mm). Irrigation helps to protect against droughts where rainfall is plentiful but uncertain. And in many circumstances, irrigation is applied to grow crops on a set schedule of cultivation and harvest. This type of irrigation also is applied to crops as flood irrigation -- water pumps or is brought to the fields along the ground to flood the crops. It is not an efficient watering method [source: United States Geological Survey].

 Water Use


The amount of water that is to be used for irrigation depends on the type of crop that is being farmed as well as the amount of rainfall in the region. There are some countries where water is used for irrigating land more than it is used for other purposes. In the US, about one-third of the water that is utilized each year is used for irrigation. Worldwide, it is more than half.

Water Sources

Water that is brought to a farm from a source of surface water, such as a lake or reservoir, usually is done so through a series of canals. In some places, snowfall and rainfall are the main suppliers of irrigation water, but in other locales, groundwater is essential. Surface water used for irrigation is stored naturally in lakes and ponds and is conveyed by rivers and streams. Groundwater collects in basins of coarse gravel and in aquifers, which are water-bearing rocks. It reaches the surface through springs. The natural sources discharge mainly in the spring and dry up in summer. Because of that natural cycle, artificial surface reservoirs are increasingly being used to store irrigation water. The largest are dams. Water also can be obtained from wells, where water from storm-filled streams is directed and collected in the ground to fill underground basins.

Some irrigation methods

Many different irrigation methods are used worldwide, including:

• Center-Pivot: Automated sprinkler irrigation achieved by automatically rotating the sprinkler pipe or boom, supplying water to the sprinkler heads or nozzles, as a radius from the center of the field to be irrigated. Water is delivered to the center or pivot point of the system. The pipe is supported above the crop by towers at fixed spacings and propelled by pneumatic, mechanical, hydraulic, or electric power on wheels or skids in fixed circular paths at uniform angular speeds. Water is applied at a uniform rate by progressive increase of nozzle size from the pivot to the end of the line. The depth of water applied is determined by the rate of travel of the system. Single units are ordinarily about 1,250 to 1,300 feet long and irrigate about a 130-acre circular area.
• Drip: A planned irrigation system in which water is applied directly to the Root Zone of plants by means of applicators (orifices, emitters, porous tubing, perforated pipe, etc.) operated under low pressure with the applicators being placed either on or below the surface of the ground.
• Flood: The application of irrigation water where the entire surface of the soil is covered by ponded water.
• Furrow: A partial surface flooding method of irrigation normally used with clean-tilled crops where water is applied in furrows or rows of sufficient capacity to contain the designed irrigation system.
• Gravity: Irrigation in which the water is not pumped but flows and is distributed by gravity.
• Rotation: A system by which irrigators receive an allotted quantity of water, not a continuous rate, but at stated intervals.
• Sprinkler: A planned irrigation system in which water is applied by means of perforated pipes or nozzles operated under pressure so as to form a spray pattern.
• Subirrigation: Applying irrigation water below the ground surface either by raising the water table within or near the root zone or by using a buried perforated or porous pipe system that discharges directly into the root zone.
• Traveling Gun: Sprinkler irrigation system consisting of a single large nozzle that rotates and is self-propelled. The name refers to the fact that the base is on wheels and can be moved by the irrigator or affixed to a guide wire.
• Supplemental: Irrigation to ensure increased crop production in areas where rainfall normally supplies most of the moisture needed.
• Surface: Irrigation where the soil surface is used as a conduit, as in furrow and border irrigation as opposed to sprinkler irrigation or subirrigation.

This information is courtesy of the Nevada Division of Water Planning, wisegeek, United States Geological survey

MEDICINAL PLANT-ASOKAM/ ASOKA/ OSAKA

Common name: asoka, Asok, Ashok, Asogam, Wu You Hua, Osaka

Scientific name: Saraca asoca (ROXB.) DE WILDE

Part Used : Bark, Leaves, Flowers, Seeds.

Commercial importance:

The bark contains tannins and some chemicals and is prescribed as a tonic. Crushed flowers and leaves are rubbed on the skin to get relief from skin diseases. When selecting trees for avenues or large gardens, it will be an excellent idea to choose Saraca asoka instead of the usual rusty shield bearer or the ubiquitous gulmohur. The dried flowers are used in diabetes and haemorrhagic dysentery and seeds are used for curing bone fractires, strangury and vesical calculi. The flowers are considered to be a uterine tonic and is used in cases like burning sensation, dysentery, hyperdypsia, scabiesin children and inflammation. It is also used in fever, dipsia, colic, ulsers and pimples. The seeds are strengthening and the ash of plant is good for external application in rheum-arthritis. It is considered as best female tonic.

How to cultivate

Soil and climate: The plant requires slightly acidic to neutral soils for good growth with

medium to deep well drained fertile soils. It grows well in tropical to sub-tropical

situations under irrigation.

Nursery raising and planting: The crop can be propagated by seeds and stem grafting. The seeds has to be collected from the matured tress in august- September. As the seeds have less life span, it will be betterto plant the seeds as early as possible. Prior to seeding, soak the seeds in water for one day and then sow them in either  nursery beds or in polythene covers filled with soil. Transfer the plants in nursery bed to polythene cover after two weeks of germination. After two years these plantlings can be used for planting in main field. The seedlings are planted in the well manured field during the rainy season with a spacing of 3* 3 meter.

Thinning and weeding: Weeding and thinning of the plants may be done as and when

required usually after 15-30 days for better growth.

Manures, fertilizers and pesticides: The medicinal plants have to be grown without

chemical fertilizers and use of pesticides. Organic manures like, Farm Yard Manure

(FYM), Vermi-Compost, Green Manure etc. may be used as per requirement of the

species. To prevent diseases, bio-pesticides could be prepared (either single or mixture)

from Neem (kernel, seeds & leaves), Chitrakmool, Dhatura, Cow's urine etc.

Irrigation: Normally grown as rainfed crop but for better yield irrigation may be done as

per requirement (weekly/fortnightly).

Harvesting/ post harvesting operation: Bark is removed from about ten years or older

tree and then it has to be sun dried. By thus time tree will also produce flowers.



MEDICINAL PLANT- ARAYAL/ Bodhi Tree, Peepal Tree, Sacred Tree

Common Name : Bodhi Tree, Peepal Tree, Sacred Tree

Scientific name :Ficus religosa

Part Used : Bark, Leaves, Tender Shoots, Latex, Seeds, Fruits.

 Commercial importance: The bark is cooling and astringent and is useful in inflammations and glandular swellings of neck. Root bark is good for stomatitis, clean ulcers and it is astringent in leucorrhoea and promotes granulations. According to Unani system of medicine, root, bark is aphrodisiac and also good for lumbago. Roots are said to be good for gout. The roots are chewed to prevent gum disease. The fruit is laxative, promotes digestion, aphrodisiac and checks vomiting. Ripe fruits are alexipharmic (an antidote or defensive remedy against poison, venom or infection), are good for foul taste, thirst and heart disease. The powdered fruit is taken for asthma. The seeds are cooling, laxative and refrigerant. Seeds are useful in urinary troubles. The leaves alone are used to treat constipation. The leaves and young shoots together are purgative (strong laxative). An infusion or decoction of the bark is used with some honey for the treatment of gonorrhoea, ulcers, skin diseases and scabies. Its power bark has been used to heal the wounds for years. 

 How to cultivate

Peepal tree is easily propagated through the seeds or through the cuttings. propagating the sacred fig (ficus religiosa) with seeds isn’t difficult. you can use a good regular potting mix. give the seeds just on the soil. to increase humidity put a glas or a freezing bag over the pot. don’t forget to air daily. place the pot on a bright location without direct sun. temperature should be +20 °c/68 °c. keep the soil moist but not wet. the sacred fig needs approx. 7 to 21 days to germinate (at 25 °c/77 °f). if the seedlings are approx. 5 cm/1.97 tall you can start slowly adapting them to your room climate with extending the airing time day by day. when they are 10 cm/3.94 inches tall they can be divided an re-potted. It can grow in any type of soil. Young peepal needs proper nourishment. It requires full sunlight and proper watering. Commonly cultivated areas Peepal tree is grown throughout India. It is mainly grown in State of Haryana, Bihar, Kerala and Madhya Pradesh. It is also found in the Ranthambore National Park in India.