System of Rice Intensification: Win-win solution

For resource-poor farmers of Goa, who are also battling changes in weather, the system of rice intensification has come as a boon.  Goaded by the State Agriculture Department and supported by the Indian Council of Agricultural Research, some farmers adopted this low-tech, low-cost approach for raising yields, and have been pleasantly surprised by the results.  The State Govt has decided to upscale the pilots to cover the entire state this year.

Rice is staple food for majority of Indians, and for resource-poor farmers, it is a major source of both income and calories.But rice is a water-intensive crop and a source of methane emissions.  A kg of rice cultivated on irrigated land requires not less than 3000-5000 ltrs of water, and continuous flooding required for its cultivation  proliferates methane-emitting anaerobic bacteria which thrive in oxygen-depleted soils caused by flooding.  In a globalised and urbanised world, with increasing population and changing diets, water-stress and unprecedented weather changes like extreme rain events, changing monsoon patterns & changing season durations, a system of rice cultivation which is input-reducing and yield enhancing is welcome to farmers.

System of Rice Intensification (SRI)  is based on the understanding that rice is not an acquatic plant and that continuous submergence under water does not allow it to reach its yield potential.  SRI  improves productivity by changing the management of plants, soil, water and nutrients and involves transplantation of very young single seedlings in widely spaced square pattern  instead of  older ones transplanted randomly in bunches  as in the traditional method.  The single and wide-spaced transplantation encourages greater root growth and wider canopy development.

The soil has to be kept moist, but well drained with sufficient organic matter to support biological activity says Satish Tendulkar,Director of Agriculture, Goa.  Thus instead of flooding, a minimum water is applied during the vegetative growth period, and thereafter a thin layer (1-2 cm) is maintained during the flowering and grain-filling period.  Weeds which is a problem in fields not kept flooded,  are handled through simple mechanical hand-held push-weeders, which also assists soil-aeration, and enhances soil-fertility by letting weeds decompose in the soil.  Farmer Ganesh Dessai says he has not used much chemical fertilizers, but relied on compost and organic manure to get the enhanced yields.

“Techniques are difficult to disseminate because they require trained extension workers says B. Vijjain, Chief Secretary of Goa, who has successfully introduced SRI to farmers in Pondicherry, and at whose instance the Agriculture Dept first introduced SRI  to farmers in Goa during 2009-2010. Since then  several blocks across talukas like Sanguem, Bardez, Tiswadi & Sattari have been adopted as pilots and have registered enhanced yields by more than 35%.  Extensive demonstrations are going on throughout the state to rope in as many farmers as possible and bring the whole state under SRI.

Says V.  Gaonkar, SRI specialist in ICAR, Ela, Goa, “SRI benefits include 50-100 % higher yields, about 50% water savings and upto 90% savings on seeds.  Better soil aeration, better soil biotics through compost and organic manure and wider spacing allows individual plants to grow strong roots and send out more tillers.  Instead of conventional 20-30 tillers, SRI sends out upto 100 with each bearing 250-500 grains as agianst 100 or so in the traditional method.

First  developed in 1980s by Fr. Henri de Laulanie in Madagascar for improving crop yields of poor farmers, SRI has become popular around the world and used in over 28 countries including China, Laos, Cambodia, Vietnam, Indonesia, etc.  This veritable revolution which can address world food crisis and climate-change related problems like reduced agricultural productivity & increasing water stress has been driven by NGOs &  progressive farmers.  On the other hand it has faced resistance from established rice research institutions like IRRI, Manila.  According to Achim Dobermann, Head of Research, IRRI, ” the claims are grossly exaggerated and cannot be verified due to lack of sufficient data”.  Prof. Norman Utholf, Cornell University, however says that ” farmers have missed this method for centuries, and scientists have missed it till recently while some are still in denial mode”

SRI offers significant benefits with strong climate change implications – reduced methane emissions, reduced water requirements and reduced use of nitrogenous fertilizers.  Since SRI does away with continuous flooding of fields, methane emissions will be significantly reduced.  Since rice fields consume more than 70% of irrigated water, the huge water savings under SRI will reduce water demand and positively impact ground water exploitation and dipping water-tables.  Similarly since around 20% of nitrogenous fertilizers are consumed by rice cultivation, there would be significant reduction in use of fertilizers since SRI works best with compost and organic manure.  It can also help the state in dismantling economically problematic subsidies on fertilizers, electricity and water-usage.

Clearly SRI is a win-win- situation.  It can address food security, improve farmers’ adaptability to climate change, help agricultural sustainablity and also help mitigation process. It is time governments around the world and agricultural academia join hands with farmers to centre-throne this revolution.

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