Water is required for agriculture as well as for other sectors (Domestic, Industries, etc) and the demand of water is increasing alarmingly. At present level, agriculture consumes over 80 per cent of total water consumption in India. The country is endowed with many perennial and seasonal rivers. The river system which constitute 71 per cent of water resources is concentrated in 36 % of geographic area. Most of agricultural fields are irrigated by use of underground water for assured irrigation, however, erratic, mansoon based rainfall is source for water for rainfed agriculture. Though water is a renewable resource, the recharge is ultimately limited to rain. Drought like situation in Indian agriculture is more common and occurs frequently in some of the part of vast geography of the country almost every year. Excessive and unbalanced use of water became a common practice to grow more & more to earn more & more. In other words, the water resources are being depleted by current practice of farming and we will be devoid of sufficient irrigation water if the trend continues in years to come. All these factors are focusing the need of judicious and efficient use of water for agricultural use.
Various type of flood method of irrigation is commonly and traditionally followed in almost whole India. This system offers liable to loss of water conveyance, distribution and evaporation. Therefore, about 30-40 % of applied water is being utilized by the crop rest is leached out; evaporated, or lost through surface run off.
The ground water level has reached to the alarming level ue to ever increasing demand of use of Ground water for irrigation. National-wide study has reveled that most of irrigation area in India are due to use of ground water. In states of Punjab, Rajasthat, Haryana, Gujarat, Andhra Pradesh, Karnataka, Tamil Nadu, etc, the level of ground water has reached to the extent of Over Exploited, Semi Critical to Critical level.
Micro Irrigation System is panacea in irrigation related problems. In this technology, field is irrigated in the close vicinity of root zone of crop. It reduces water loss occurring through evaporation, conveyance and distribution. Therefore high water use efficiency can be achieved (
Irrigation efficiencies | Methods of Irrigation | ||
Surface | Sprinkler | Drip | |
Conveyance efficiency | 40-50 (canal) 60-70 (well) | 100 | 100 |
Application efficiency | 60-70 | 70-80 | 90 |
Surface water moisture evaporation | 30-40 | 30-40 | 20-25 |
Overall efficiency | 30-45 | 50-60 | 80-90 |
Micro-irrigation system is the best available way to utilize water and fertilizer efficiently under farm conditions. The type of Microirrigation system may very with the type of crop selected and amount of water available for irrigation
Crop group wise advisable Micro Irrigation System | ||
Crop | Crop Spacing | Adjustable Micro Irrigation System |
Horticulture Crop | 12 m to 3 m between crop raw. (wide spaced) | Drip Irrigation System / Pours Pipe |
Crops fruit part under ground like Potato, Groundnut, Turmeric, Ginger, Vegetables, Medicinal Crops etc. | Less then 1 m between crop raw. (Narrow) | Drip Irrigation / Sprinkler Irrigation / Raingun |
Field Crops like Cotton, Castor, Tobacco, Pulses, Sugarcane, Banana, Vegetables etc. | Less then 3 m between two crops | Drip Irrigation |
Fodder Crops / Nursery Raising of Vegetables, Ornamental Crops etc. | - | Sprinkler Irrigation / Raingun |
The advantages of drip irrigation are:
Crop-wise water saving over surface irrigation method and increase in yield is presented in table
Crop | yield (q/ha) | Irrigation | ||||
Surface | Drip | % Increase | Surface | Drip | % Saving | |
Beet root | 5.7 | 8.8 | 54 | 86 | 18 | 79 |
Bitter gourd | 32 | 43 | 34 | 76 | 33 | 57 |
Brinjal | 91 | 148 | 63 | 168 | 64 | 62 |
Brocolli | 140 | 195 | 39 | 70 | 60 | 14 |
Chilli | 171 | 274 | 60 | 27 | 18 | 33 |
Cucumber | 42.3 | 60.9 | 44 | 109 | 41.7 | 62 |
Okra | 155 | 225 | 45 | 54 | 24 | 56 |
Onion | 284 | 342 | 20 | 52 | 26 | 50 |
Potato | 172 | 291 | 69 | 60 | 27.5 | 54 |
Radish | 10.5 | 11.9 | 13 | 46 | 11 | 76 |
Sweet potato | 42.4 | 58.9 | 39 | 63 | 25 | 60 |
Tomato | 61.8 | 88.7 | 44 | 49.8 | 10.7 | 79 |
Banana | 575 | 875 | 52 | 176 | 97 | 45 |
Grapes | 264 | 325 | 23 | 53 | 28 | 47 |
Papaya | 130 | 230 | 77 | 228 | 73 | 68 |
Pomegranate | 34 | 67 | 97 | 21 | 16 | 24 |
Watermelon | 82.1 | 504 | 514 | 72 | 25 | 65 |
Even having many benefits the reach of MIS among the farmers restricted. Though, the government is trying to promote the technology through part financial support to offset its high initial cost syndrome. Few adoptions were observed in the decade of eighties and nineties
Decade | Focus of Research/ extension |
Seventies | Comparisons of micro irrigation system with conventional systems in terms of water savings and yield enhancements. |
Eighties | Estimate water requirements, modifications of crop geometry and use of mulches in drip irrigated fields for realizing the potential benefits of the system |
Nineties | Develop hardware and software for cost reduction, design modifications and fertigation and chemigation |
Twenty first century | Precision farming, including the use and application of software and more efficient instruments in agriculture besides the use of simulation and modeling of moisture and nutrients movement under different soil and dripper characteristics |
Dr. Sarvesh Kumar Shah
H-12, Komal Enclave, Shantivan, Paldi, Ahmedabad-380 007
sarveshshah@gmail.com