Towards adopting nanotechnology in irrigation: Micro irrigation systems

India is predominantly an agricultural country and even with current orientation towards services, still agriculture contributes ¼th of total GDP of the country, 15 percent of total export and 65 % of total population’s livelihood. After independence, India has made remarkable progress in increasing food production and productivity, credit goes to concerted efforts made under various Agri revolutions. For agriculture Land and Water are two most important resources. Of which, water (irrigation) becomes lifeline of agriculture. It is a truth in agriculture “if we fail in irrigation, we will fail in agriculture”.

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 (Table 1). The unirrigated rainfed cropped area, could be irrigated with the water saved with this technology become a potential source of food production for the benefit of country’s food security.

 Table 1: Irrigation efficiency under different methods of irrigation

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 (Table 2). However, modern technology was developed in Israel. Since MIS is a well planned and scientifically designed way of farming, it also provides option for Crop diversification. Unlike surface irrigation, drip irrigation is more suitable and economical if it is introduced in water scarce areas having undulated topography, shallow and sandy soils barren and for wide spaced high value crops. It reduces cost of cultivation, increases productivity and reduces energy (electricity) consumption.

 Table 2: Crop group wise advisable Micro Irrigation System

 The advantages of drip irrigation are:

• Minimized fertilizer/nutrient loss due to localized application and reduced leaching.
• High water application efficiency.
• Leveling of the field not necessary.
• Ability to irrigate irregular shaped fields.
• Allows safe use of recycled water.
• Moisture within the root zone can be maintained at field capacity.
• Soil type plays less important role in frequency of irrigation.
• Minimized soil erosion.
• Highly uniform distribution of water i.e., controlled by output of each nozzle.
• Lower labour cost.
• Variation in supply can be regulated by regulating the valves and drippers.
• Fertigation can easily be included with minimal waste of fertilizers.
• Foliage remains dry thus reducing the risk of disease.
• Usually operated at lower pressure than other types of pressurised irrigation, reducing energy costs.

Crop-wise water saving over surface irrigation method and increase in yield is presented in table (Table 3).

 Table 3: Crop-wise water saving and increase in yield

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 (Table 4). Putting all together efforts of all machineries under one, total coverage of land under MIS is less than 1 per cent, which underlines the need of integrated efforts to be made by all stake holders. The rural electrification is another major constraint for the popularization of drip systems among farmers. The high care as well as meager crop and soil specific technology are few major constraints for deeper reach of the technology among farmers.

Table 4 : Decade wise development in the field of Micro-irrigation

Promotion of adoption of Micro Irrigation System in India

1. Concerted efforts taken by the Government / NGO and the MIS companies for widespread awareness about the usefulness of the wonderful technology.
2. Efforts should be made to ensure the production and supply of good quality microirrigation system to the farmers by enforcing strict quality control measures.
3. Microirrigation should be made an integral part of all irrigation projects.
4. The microirrigation system manufacturers should also guide the farmers in adopting suitable agronomic practices along with microirrigation.
5. After sales service should be strengthen. 
6. Technological intervention is required to cut down the cost of Micro-irrigation system.

Dr. Sarvesh Kumar Shah
H-12, Komal Enclave, Shantivan, Paldi, Ahmedabad-380 007
sarveshshah@gmail.com