Miraculous or Mythological? The System of Rice Intensification

Created on 30 Oct 2007 by Marcus Williamson

The History of S.R.I.

In 1983, a French Jesuit priest called Father Henri de Laulanie working in Madagascar made a surprising observation: after an unusually dry period, rice production actually increased. De Laulaine started to conduct experiments, and eventually proposed an alternative method of growing (lowland) rice, which became known as the 'System of Rice Intensification'. In this system, rice seedlings are transplanted into rice fields at an earlier stage of development than is common practice, and they are spaced much more widely. The most important difference is that the rice field is not flooded- the soil is irrigated periodically so that it can stay in moist condition (as pictured). The soil is treated with only organic fertilizers, and weeded regularly. It was found that this method of growing rice increased the yield by as much as double, while decreasing water and seed consumption.

De Laulaine established an NGO to promote SRI in Madagascar, called Association Tefy Saina in 1990. Shortly after, Norman Uphoff, the head of the International Institute for Food, Agriculture and Development at Cornell University, visited the Association and saw the results of S.R.I. for himself. Amazed, he started to promote S.R.I. in Asia and it is mainly through his work that S.R.I. has become world famous, and is now being tested in countries including Afghanistan, China, Cambodia, Indonesia, India, Iran, Nigeria, Colombia, Peru and Zambia.

Theory and Practice of S.R.I.

The theoretical underpinning of S.R.I is that, contrary to the received wisdom, rice does not grow well in an immersed/anaerobic environment. The proponents of S.R.I claim that, in fact, immersion of rice in water interferes with the development of its root structure and reduces its growth potential. They claim that without immersion and properly aerated soils, growth is much higher.

How much higher? In one paper, Dr. Uphoff claims that under S.R.I, rice yields can increase to 15-20MT/Ha, compared to a world average of 3.8MT/Ha for irrigated rice. He also claims that seed use is reduced by 90%, and there is a 25-50% reduction in water consumption. If these figures are correct, S.R.I. is a discovery of the first order of importance.

The Skeptics

One of the things that makes S.R.I. so interesting is that it is, in fact, intensely controversial. Many of the world's leading agronomists and rice specialists claim that the benefits reported by proponents of S.R.I. are impossible. How can this be so?

The main reason for this skepticism is that several high-profile tests of S.R.I., for example one conducted in China and reported in Nature magazine, tests conducted by the International Rice Research Institute, and national trials in Thailand, showed no yield benefits from the S.R.I. method. This lead skeptics to suggest that the reports of huge yield increases were simply 'agronomic UFOs' (Unconfirmed Field Observations). Skeptics pointed out that the majority of reports of yield increases had not come from proper scientific studies in which all of the variables were properly controlled, an