Los Baños, Philippines
October 29, 2002

The remarkable ability of biodiversity to help farmers improve their livelihoods while protecting the environment and their health is emerging from the latest rice research.

The news was announced on the eve of the annual general meeting of the Consultative Group on International Agricultural Research (CGIAR) in the Philippine capital, Manila. The CGIAR is a strategic alliance of the 16 Future Harvest research centers, 22 developing countries, 21 industrialized countries, and many hundreds of partner organizations who work together to mobilize science to benefit poor people engaged in or otherwise dependent upon agriculture in the developing world.

Research projects conducted by scientists from the International Rice Research Institute (IRRI), which is a CGIAR center based in the Philippines, and their collaborators in China have found that farmers can use biodiversity to improve their incomes and profitability while controlling pests and diseases with fewer pesticide applications. IRRI has made biodiversity a central research focus for more than a decade and runs projects exploring its potential in most Asian nations.

Some of the most promising research has studied the planting of traditional rice varieties either alongside or in place of the modern, high-yielding rice varieties normally grown today by most of the world's 200 million rice farmers. Many of these traditional varieties command a higher price in the
market because of their popularity with consumers but are rarely grown due to their low yields, susceptibility to disease or other drawbacks.

The projects highlight IRRI's efforts to protect and conserve the biodiversity of the rice industry, especially in the Philippines and other Asian nations. Seeds of 3,144 distinct Philippine rice lines - including 115 wild species and 561 varieties from tribal Ifugao areas - are available for
appropriate research use at the International Rice Genebank at IRRI. The institute's scientists, their Filipino counterparts, extension workers, anthropologists, missionaries, Peace Corps volunteers, and farmers have collected these seeds over a number of years. IRRI has provided 577 duplicate sets of seeds to the Philippine Department of Agriculture and 1,367 sets to the Philippine Rice Research Institute (PhilRice).

Next month, the International Rice Genebank will celebrate its 25th anniversary. More than 100 countries have, like the Philippines, donated germplasm to the genebank for safekeeping at IRRI (the National Seed Storage Laboratory in the United States holds a duplicate, backup set under the
exclusive control of the International Rice Genebank). The collection now holds more than 108,000 samples of cultivated rice and wild species, most of which are traditional varieties belonging to O. sativa.

Confirming the success of conservation and utilization efforts in the Philippines are several recent projects in which IRRI researchers and their local partners have drawn on genebank stocks. In the southern Philippine island of Mindanao this year, the institute is conducting an on-farm, participatory testing program that includes about 50 farmers.

The farmers are testing about 20 improved and traditional upland varieties and have commented favorably on two IRRI-supplied traditional upland varieties, Azucena and Dinorado. The farmers had lost most of their own seed for these varieties following a shift out of upland rice into maize. The seed that remained with them had become badly mixed with other varieties.

Farmers supplied with new stocks of pure seed from IRRI said they were impressed with the results and wanted to plant the varieties again next year, as they grew well and commanded a good price. In an initial survey, farmers rated the IRRI-supplied traditional varieties above both their own traditional material and modern varieties.

In another project in 2001 in the Cagayan Valley of the northern Philippines, local farmers were for the first time introduced to a system of double cropping that included a traditional variety known as wag-wag, which had all but disappeared from local farms. Farmers said the strengths of the system were increased profitability, reduced input costs, a better market price, and the potential for adding crops other than rice, such as mung beans, in the wet season.

IRRI had earlier collaborated with PhilRice in the distribution of two tons of rice seeds of 20 modern and eight traditional varieties. This was to assist farmers in the Cagayan Valley who lost their seed stocks when crops failed because of the El Niño of 1997 and Typhoon Loleng in 1998.

Meanwhile, in China, in what The New York Times described as a "stunning success" and "one of the largest agricultural experiments ever," an IRRI-led team of scientists from around the world found a new way to use biodiversity to control a major disease in rice with reduced applications of chemicals.

By planting different types of rice alongside each other, researchers found they could almost completely control rice blast, a disease that can cost the rice industry millions of dollars a year. Known in scientific circles as "exploiting biodiversity for sustainable pest management," the idea is
hardly new to many farmers. What is new is how researchers are using cutting-edge science in their collaboration with farmers to determine how to use this strategy for maximum effect.

Thousands of farmers in the province have now embraced the technique because it improves yields and incomes while reducing their reliance on chemicals. The strategy calls for farmers to interplant one row of glutinous rice - which commands a high price because of its popularity with consumers but is susceptible to blast - between four to six rows of blast-resistant hybrid rice in a repeating pattern.

Simple as the technique sounds, refining interplanting to make it profitable has been a challenge. The project coordinator, Tom Mew, who is also head of IRRI's Entomology and Plant Pathology Division, has dedicated decades to working with farmers to control the pests and diseases that can devastate
their crops.

Dr. Mew and his team reasoned that planting a wide area with a single variety of rice, as has been done in the Red River Valley of Yunnan, invites epidemic outbreaks of such diseases as blast. The pathogen, having adapted to the defenses of one plant, is then able to attack the remainder of the crop. But a crop that exhibits biodiversity will surround the pathogen with dissimilar plants, making it harder for the disease to spread.

"Our challenge was to simulate through varietal deployment on actual rice farms a situation similar to natural diversity and achieve the resistance to pests or diseases that such diversity supplies," Dr. Mew said. "We focused on interplanting rice, or growing different varieties in the same field. At the beginning, there was doubt and skepticism."

An experiment in 1997 covering a few hectares suggested that interplanting could achieve 92 to 99 percent control of rice blast while boosting yields by 0.5-1 ton per hectare and improving farmers' incomes.

The following year, cooperating farmers interplanted 812 hectares with hybrid and glutinous rice. They sprayed the crop with fungicide only once. Yields reached 9 tons of hybrid rice and nearly 1 ton of high-value glutinous rice per hectare. Even more impressive was that the incidence of blast in glutinous rice fell to 5 percent within the interplanted crop, from a common level of 55 percent in monoculture, and the yield loss dropped from 28 percent to nothing at all.

In 1999, the interplanted area expanded to 3,342 hectares, and cooperating farmers reported that the technique was providing them with an average of US$281 more income per hectare. By the end of 2001, about 60 percent of rice farm households in the indica rice area of Yunnan Province had adopted
interplanting of rice varieties, and the area under mixtures had expanded to 106,000 hectares. This year, rice interplanting covers an area of more than 200,000 hectares in 101 counties of Yunnan.

The IRRI-Yunnan research team plans to extend the approach to other provinces in southwest China and to other rice-producing countries, including the Philippines, Indonesia, Laos and Vietnam.

IRRI is the world's leading international rice research and training center. Based in the Philippines and with offices in 11 other countries, it is an autonomous, nonprofit institution focused on improving the well-being of present and future generations of rice farmers and consumers, particularly those with low incomes, while preserving natural resources. IRRI is one of 16 Future Harvest centers funded by the Consultative Group on International Agricultural Research (CGIAR), an association of public and private donor agencies.

For more information, visit the websites of the CGIAR or Future Harvest

Future Harvest is a nonprofit organization that builds awareness and supports food and environmental research for a world with less poverty, a healthier human family, well-nourished children and a better environment. Future Harvest supports research, promotes partnerships and sponsors projects that bring the results of agricultural research to rural communities, farmers and families in Africa, Latin America and Asia.