CGIAR Scientists Deploy Infra-Red Scanners in Fight Against Hunger: Five Developing Countries to Test New Crop-Boosting Technique

In a part of the world where millions of farmers still rely on hand tools to prepare the soil, CGIAR researchers are about to introduce a new technology that could set the stage for major increases in African food production.

Using infra-red light to detect minute differences in soil composition and structure, a process known as infra-red spectroscopy, the new technique provides farmers with precise, timely information about how to improve depleted soils and boost crop productivity.

Scientists at the World Agroforestry Centre (ICRAF), in cooperation with private sector researchers at Analytical Spectral Devices of the United States and the German company Bruker Optik, have adapted the technology to African farm conditions. It is currently being used in Western Kenya as part of the Millennium Villages Project, and in a World Bank initiative to halt land degradation and restore thousands of hectares of degraded farm land to production.

World Food Prize winner Pedro Sanchez predicts that within a decade most developing countries will be using the technique for soil and plant analysis. "With infra-red, we have a tool that can collect data on soil quality and plant nutrition from thousands of locations, geo-reference it, and predict quickly and inexpensively how improved crop varieties will respond to fertilizer at a given location," he says. Sanchez, who serves as director of the UN Millennium Project's Hunger Task Force, notes that achieving the Millennium Development Goals will require farmers, development agencies, and the private sector to collect information from large numbers of field trials.

The effectiveness of the technique was first demonstrated in 2000 when ICRAF scientists uncovered massive soil erosion pluming into Lake Victoria. The problem, they note, was all but unrecognized until the cost-effectiveness of IR made it possible to conduct a diagnostic surveillance survey. In a more recent test, IR was used to pinpoint soil degradation in the 3,500 km 2 Nyando River Basin to assist Kenyan scientists set targets for a World Bank-Global Environment Facility initiative.

The use of infrared spectroscopy (IR), Sanchez notes, represents a major advance in technology and field diagnostics. The technique uses only light for rapid, non-destructive analysis of soil and plant materials and is similar in many respects to digital photography: reflectance from a soil sample is collected across a range of infrared wavelengths. Working from a digital scan, a "reflectance fingerprint" is obtained from which technicians can predict the nature of multiple soil properties. The technique is fast, economical, and does not require costly chemicals used in conventional soil analysis.

IR's most important attribute, however, is its ability to predict soil and plant performance, thus bypassing the need for conventional testing. Tests have also shown that infrared is highly effective when used in conjunction with global positioning systems and satellite sensing to produce inexpensive maps that can pinpoint soil and plant nutritional problems.

ICRAF researchers note that IR can also be used to measure implementation and compliance in environmental service payment schemes. The potential for widespread adoption of IR by public and private sector providers of on-farm advisory services, they add, is now quite considerable. Modern IR technology, they say, could provide farmers with to access diagnostic support at affordable prices and eliminate the need to establish costly soil analytical labs.

Keith Shepherd, the project's lead scientist, says that with one IR instrument, rural laboratories will be able to analyze not only soils and crops, but also a range of agricultural inputs and products, including manures, animal feeds, grains, and tree products.

Shepherd points out that once the equipment is operational, costs are virtually zero. In contrast, the cost per sample prduced by a conventional laboratory easily exceeds $50. He notes that the equipment, which is easy to maintain, was recently installed in a rudimentary laboratory at Mali's Institut d'Economie Rurale.

In time, the development of IR technology, adds ICRAF Director General Dennis Garrity, should help farmers in much the same way that mobile telephones have benefited consumers, i.e. by providing access to a service that is in high demand without the need to construct costly physical infrastructure.

"Within a decade extension providers in many countries will be using handheld IR equipment as their principal analytical tool for soil and plant analysis," Garrity adds. Until then, suitcase-size IR instruments can be purchased for just $70,000, little more than five percent of the cost of equipping a large conventional laboratory. The first hand-held IR units, he predicts, could be available for use within three years.

In addition to Kenya and Mali, IR technology is currently slated for use in India, Mozambique, and Uganda.

The CGIAR wishes to thank Ed Sulzberger for contributing this story.