Saving water for food security in India

Water scarcity: a global issue
Water scarcity is becoming more and more a global concern. With increasing population and competing demands from agriculture, industry, and urban areas, water is quickly turning into a limited resource. This problem is aggravated by abnormal climate patterns and diminishing water quality. By 2025, it is predicted that two-thirds of the world will experience water scarcity. Based on a study of T.P. Tuong and Bas Bouman, water scientists of the International Rice Research Institute (IRRI), 90% of fresh water in Asia is diverted to its irrigated areas. If the prediction does come true, Asia’s food production will be greatly hurt.

The areas in red will have limited water supply, while the areas in blue will have little or no water scarcity. The regions in orange will still have available water supply, but the costs to obtain water will be high. The shaded regions indicate countries that will import more than 10% of their cereal consumption in 2025.

In India, signs of water scarcity are already evident in agricultural areas. Their water table is dropping due to overpumping of groundwater for agriculture and domestic use, thus greatly affecting the long-term sustainability of water resources for food production. A water table is the top layer of groundwater. In times of serious drought, water table levels may drop and wells may run dry.

Another problem that farmers are facing is the high cost of fuel, which is needed to run the pump to draw out groundwater. This affects the profitability of production. Oftentimes, farmers earn less from their harvest as compared to their expenses, so some of them are forced to stop growing crops. In some areas, farmers use electricity to run their pumps, but the supply of electricity is erratic. The inconsistent supply makes it hard to ensure the availability of irrigation when it is needed by the crop.

Rice as a focus of water-saving initiatives
Rice is the most important agricultural crop and the major user of available fresh water in Asia. It is one of the major crops in India, and in some areas it is grown subsequently with wheat. The usual way of growing rice is by transplanting in flooded and puddled soil. Rice is grown with standing water throughout the growing season. This practice of growing rice needs a relatively large amount of water compared with other cereals. However, most of the supplied water in the field evaporates in the atmosphere or drains deep down and across the soil layer.

With the looming problem of water scarcity, IRRI rice scientists and hydrologists, and partners from the national agricultural research and extension systems, have begun conducting research activities with farmers to control this problem. One of the potential water-saving technologies being studied is the aerobic rice system. The Irrigated Rice Research Consortium and the Challenge Program on Water and Food are two programs that support the ongoing research activities on aerobic rice in India through the Water Technology Centre (WTC) of the Indian Agricultural Research Institute (IARI).

Working with farmers
The aerobic rice system is a rice cropping system that uses varieties that can be grown without standing water (similar to upland rice), but can produce yield values that are only 20–30% lower than those of lowland rice (grown with standing water). Good management practices are applied to ensure the productivity and sustainability of the system.

The participatory nature of the activities guarantees that the system is adjusted to the common farmers’ practice. The WTC has been working with farmers in Bulandshar, Uttar Pradesh, where they practice a rice-wheat cropping system. Wheat is a rabi (dry-season) crop, while rice is a kharif (wet-season) crop. During the kharif season, they test the performance of potential aerobic rice varieties. Factors considered for selection are yield, water savings, and farmers’ preference (which includes eating quality and marketability of the variety).

Dr. Christine Kreye (right), an international research fellow at IRRI, interviews Dr. Sarwan Kumar Dubey, senior scientist from WTC, and a farmer who participate in the aerobic rice testing. At the time of the visit in March 2006, wheat was still the standing crop. (Photo by R. Bayot)

Ten rice varieties were tested in farmers’ fields in three different villages. The varieties used were the better-performing ones that were tested under aerobic conditions at the IARI experiment station. Pusa Sugandh 3, an aromatic rice variety with relatively high marketability potential, performed particularly well in this variety selection activity.

Farmers also observed the performance of the varieties under different irrigation treatments. In one part of the field, the farmers irrigated frequently to keep the soil near saturation. In another section, they irrigated twice a week (except when it rained) to keep the soil moisture at field capacity (approximately when the tensiometer reading is 20 kPa). In the remaining part, irrigation was done once a week to maintain soil moisture at 40 kPa (except when it rained). These treatments were compared with the traditional farmers’ practice. The varieties tested for this experiment were Pusa Rice Hybrid 10 and Pusa Sugandh 3. These varieties performed well under aerobic conditions in the experiment field. Significant water savings (around 60%) were observed and yields were on a par with that of puddled transplanted paddy. However, the common constraint seen by farmers who tried this system were the weeds.

The aerobic rice system produced promising results on its initial year of testing. The IRRI’s aerobic rice team and WTC counterparts will continue to look at the sustainability and profitability of the system.
Other water-saving technologies and indigenous practices are also being tested in the field to determine the comparative advantages of the technologies. In their fields, farmers have been testing the transplanting of rice on beds. Farmers irrigate roughly once a week, and keep water at a half-furrow depth.

Cooperating farmers pose in front of an aerobic rice field planted with Apo variety (IR55423-01) in October 2006. This promising aerobic rice variety was tested in the Philippines, and it is now also performing well under Indian field conditions. (Photo by C. Kreye

Indian farmers greatly value rice as an economic crop, especially the aromatic varieties. They yearn for cultural practices that can reduce irrigation requirement and pumping cost. It is important for them to reduce the cost of production to increase crop profitability.

IRRI is very much aware of their plight. With the help of its partners, IRRI continues to develop technologies such as aerobic rice to answer farmers’ concerns.

Ruvicyn Bayot (r.bayot@cgiar.org)

 

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