Filipino melon grower Denis Miguel was intrigued to hear of a young Indian farmer who in 2011 had broken the world record for growing rice by using an unconventional method of cultivation that needed only half as much water and one-tenth as many seeds but resulted in spectacular yield increases.

Miguel, from Isabela province, had never grown rice before, but he teamed up with a local rice farmer to try out the system. Last year, he reaped the equivalent of 10.8 tons of rice per hectare, or four times as much rice as the farmer usually grew on that land.

He was astonished. A harvest of 10.8 tons per hectare on a rain-fed farm which used to produce only 2.5 tons was a great success. I was a newbie rice farmer. It was my first attempt at rice farming. It was an eye opener to all the people who were witness, he said in an email.

Miguel is not alone. Reports from China, India , Southeast Asia and Africa suggest that average yield increases of 20 to 50 percent are regularly being achieved by farmers adopting the system of rice intensification (SRI), which aims to stimulate the root system of plants rather than trying to increase yields in the conventional way by using improved seeds and synthetic fertilizers.

Rice is the major staple crop of nearly half the world and is primarily grown by small farmers. Seedlings are traditionally planted in large clumps in flooded fields. One kilogram of rice typically requires about 660 gallons of water.

SRI, in contrast, involves the careful spacing of fewer but younger plants, keeping the topsoil around the plants well-aerated by weeding, using manure and avoiding flooding.