The soil moisture stress observed this year in several parts of the country owing to deficient and erratic rainfall in the first half of the monsoon season may no longer remain a major yield-depressant. Crops in water-short areas can now be saved thanks to a recently developed water absorbent cellulosic gel that, if added to the soil, can imbibe the available water, retain it over a period and release it for use by plants when they need it. In other words, it ensures the most efficient use of water for raising crops in rain-dependent areas that account for over 55 per cent of India’s total farm land.
Scientists of the New Delhi-based Indian Agricultural Research Institute (IARI), also called the Pusa Institute, who have developed this innovative semi-synthetic hydrophilic polymer gel, claim that it has several unique features that set it apart from other liquid-absorbing gels used in biomedical and, to some extent, agricultural applications. Named appropriately as “Pusa Hydrogel”, this super absorbent product is capable of mopping up and holding water equivalent to nearly 350 to 500 times its dry weight. Thus, only a small quantity of this gel – 2.5 kg to 3.75 kg – is required to be added per hectare of land, against as much as 10 kg of other gels used elsewhere in the world.
The Pusa Hydrogel is evolved specifically to work efficiently in the hot tropical and semi-tropical climate of the country where most other gels fail to perform properly. In fact, its absorption capacity increases as the temperature rises to 45 degrees Celsius or above. Besides, Pusa Hydrogel meets most other prerequisites for use in agriculture, such as the ability to co-exist with fertilisers, notably the most-used urea, capable of lasting at least for one full crop season and free of any toxin that can make its use environmentally-unsafe. Additionally, this product has been found to improve the physical health of the land by loosening the compact soil to enhance crop productivity.
The usefulness of Pusa Hydrogel has been borne out by the promising results of its trials on farmers’ fields by IARI and other bodies in several states. Many farmers in Uttar Pradesh have reported yield enhancement of 17 per cent, on average. Many others have found this gel to improve seed germination and reduce the requirement of fertilisers, besides boosting physical health and fertility of the soil. These trials involved a diverse range of key cereals, oilseeds, vegetables and commercial crops, such as paddy, wheat, maize, cotton, sugarcane, groundnut, soyabean, mustard, potato, cauliflower, turmeric, opium and chrysanthemum.
IARI scientists are now working on up-scaling the utility of Pusa Hydrogel by doping it with micronutrients that are often scarce in the soils of rainfed areas. This would boost the usefulness of this gel to farmers. IARI Director H S Gupta maintains that the development of Pusa Hydrogel is another proof of India’s ability to conduct world-class agricultural research and come up with innovative solutions to commonly faced problems. Other countries are now trying to fabricate such a valuable product. However, IARI has patented Pusa Hydrogel in India and has initiated the process to get an international patent as well.
Significantly, the technology for the commercial production of Pusa Hydrogel has been licensed to six Indian companies, three of which have already begun pilot-scale production and marketing in different states. Buoyed by the encouraging response from farmers, some of these companies have begun to explore the possibilities of introducing this product in other tropical countries, chiefly in Africa.
The current cost of Pusa Hydrogel ranges between Rs 1,000 and Rs 1,400 a kg, but the economic returns from its application are as high as five to seven times the cost. Scientists are sure that bulk production and technology refinement can substantially lower its cost in the future. Besides, IARI has approached the government for offering a subsidy on this gel – as is being done in the case of fertilisers and some other water-saving equipment like drip irrigation – to increase its affordability for resource-poor farmers in the rainfed tracks. If this request is conceded, it would hasten the spread of Pusa Hydrogel.
