THE HAGUE, – Scientists announced today that a major agricultural transformation is sweeping across Asia’s breadbasket regions that could have significant implications for charting a course toward more ecologically-friendly, higher-producing, cost-effective agriculture among all groups of farmers in Asia.
So-called “low-till” farming, which does away with intensive and repeated plowing of farmers’ fields, is increasing harvests, reducing water use by as much as 30 to 50 percent, and requiring less fuel for running tractors on farms. Because there are one-half to two-thirds fewer weeds, herbicide use is reduced. Farmers living in four countries—Bangladesh, India, Nepal, and Pakistan—are taking up low-till agriculture in such numbers that scientists say the impact in the region could be as great as the Green Revolution of the 1970s.
The success of the approach comes at an opportune time as water scarcity in Asia and, more specifically, a three-year drought in Pakistan, threaten the region’s rice and wheat yields. The transformation in farming is largely the result of pioneering agricultural research and promotional work begun in the region by the Mexico-based International Maize and Wheat Improvement Center (CIMMYT).
CIMMYT works in partnership with the national research programs of South Asia in an alliance known as the Rice-Wheat Consortium for the Indo-Gangetic Plains (RWC), which also includes the Philippines-based International Rice Research Institute (IRRI).
RWC has been funded in large part by the International Cooperation of the Government of the Netherlands (DGIS). Both CIMMYT and IRRI are Future Harvest Centers. Future Harvest is a global, non-profit organization based in Washington, D.C. that builds awareness and support for food and environmental research around the world.
“This region of 1.3 billion inhabitants is beset by overcrowding, poverty, and misery,” said Professor Timothy Reeves, director general of CIMMYT. “To feed soaring populations, farmers must increasingly use more fertilizer, water, and herbicides to get the same or greater crop yields from their land. Low-till agriculture enables them to increase their productivity while at the same time decreasing—not increasing—these inputs. This new agricultural revolution in South Asia is poised to be a greener revolution than the one that took place in the 1970s.”
“South Asia is facing an extreme crisis in water—the lifeblood of this region—and that could be absolutely devastating,” said Peter Hobbs, PhD, a natural resource agronomist with CIMMYT and one of the lead scientists on these efforts in the region. “Without conservation of water through practices like low-till agriculture, this region will become dependent upon imported food, which no one can afford. This would create inevitable food shortages and severe malnutrition in a population where 40 percent of the people live on less than US$2 per day.”
More than 150 million people depend solely upon the region’s rotational cropping of rice and wheat during the wet and dry seasons. In terms of intensity of food production, it is the most important agricultural system for feeding South Asia’s burgeoning population, both urban and rural.
Many parts of the world, including the European Union, are debating the restructuring of agricultural policy to be more focused on environmental and food security needs. Low-till practices are part of an overall trend toward more ecological farming in developing countries. And as the United Nations Development Programme highlights in its recent Human Development Report, access to technology by all—particularly those in developing countries—will play a critical part in reducing poverty and suffering.
“Low-till is one of the best examples in the world of technologies working for both people and the environment,” said Reeves. Currently, low-till practices are being used for sowing wheat after the harvesting of rice. An example of its rapid spread is found in India and Pakistan, where the area sown to low-till agriculture increased from a modest 3,000-plus hectares in 1998-99 to surpass 100,000 hectares in 2000-2001. It is anticipated that this area could surpass 300,000 hectares next year and soon reach one million hectares.
Low-till agriculture: Low-tech, low-cost
Plowing is customarily done to break up soil into smaller particles that form a better soil structure for planting the next crop. Specifically in Asian rice-wheat cropping systems, farmers must make as many as 6-12 tractor passes across the field when they plant wheat after rice, because the soil is wet and muddy or cloddy. To grow rice, farmers plow the wet soil, which breaks down the soil structure and allows water to “puddle” rather than sink into the soil. To plant wheat, farmers have to re-build the soil by repeated plowing.
“Plowing significantly delays planting of wheat,” said Hobbs. “As a result, the crop often does not mature before the onset of the hot, dry season before the monsoon. The dry heat shrivels the grain and reduces harvests and incomes.”
In addition, plowing exposes the soil to air, which oxidizes soil matter and roots. Over time, organic matter—an important source of nutrients in the soil—is depleted. Soil moisture is also depleted, increasing the need for water through irrigation.
Low-till agriculture, however, leaves much or all of the soil surface and existing ground cover undisturbed during the planting process. It generally makes use of a “planter” or “seed drill.” In one pass across a field, the planter places seeds and fertilizer through the rice straw left standing from the previous harvest into the soil below. Because the leftover straw remains anchored into the soil, those roots provide channels for wheat roots to grow; a habitat for beneficial insects to prey on invasive insects; and, as it decomposes, a natural fertilizer of organic matter for the wheat crop. Locally manufactured planters are fairly inexpensive at US$400-500 each and can sow approximately 80 hectares (200 acres) per cropping season. Farmers with little cash can rent this equipment.
The low-till technology is designed to be accessible to farmers with limited resources who have no equipment, little cash, and often very little land. Seventy-four percent of the farmers who used low-till between 1999-2000 in Haryana State, India, did not own tractors and are considered resource-poor farmers. These farmers rented planters at a low cost.
Other low-till practices are also being used in the region, such as raised soil beds—or “bed planting”—and direct seeding of presoaked wheat seeds into still-moist rice fields—or “surface seeding.”
“Low-till practices have caught on like wildfire among farmers, with the area being planted to low-till agriculture increasing ten-fold per year,” said Hobbs. “Manufacturers cannot make planters fast enough to meet the demand from farmers.”
Benefits of low-till agriculture include:
- Saving water. As much as 30 to 50 percent of water per year is saved through low-till techniques that increase the amount of moisture retained by the soil when it is plowed less. Low-till helps to save water in three ways: the soil conserves more moisture at planting, the crop is ready for harvest before the hot season arrives, and irrigation water flows faster over a field that has not been tilled, so less water is pumped. Low-till practices could save as much as 5 billion cubic meters of water each year in the region.
- Increasing harvests. Planting wheat immediately after harvesting rice means the crop is planted three or four weeks earlier than it can be with a plowing system. This enables the crop to mature fully before the hot, dry weather sets in, thereby increasing crop productivity and income.
- Reducing greenhouse gas emissions. Decreasing or eliminating tractor and water pump usage means less fuel is burned—as much as 75 percent or more per year—and fewer greenhouse gases are emitted—as much as 800,000 tons of carbon dioxide less per year, if low-till were adopted widely.
- Causing fewer weeds and thus fewer herbicides. Leaving the soil less disturbed by intensive plowing causes fewer weeds to germinate. In addition, an earlier start to planting wheat means that the wheat crop more effectively shades out growth of weeds, like the problem Phalaris weed, popularly known as the “twin of wheat.” Because there are as many as one-half to two-thirds fewer weeds, the need for herbicides declines.
- Reducing production costs. Farmers are keen to adopt low-till because it reduces land preparation costs, and yields are higher. If farmers could reduce tillage in rice production as well, the benefits would be even greater.
Local adaptation and adoption
Since research began in 1984, low-till farming techniques in South Asia have been refined to meet the specific needs and circumstances of the region. The process of moving to low-till agriculture was slow to begin because it meant a change in mindset for both scientists and farmers in plowing the land. But once the benefits were realized, low-till agriculture has spread rapidly among farmers. Farmer involvement and experimentation at the local level has been key to this process.
“These benefits could not be realized if it weren’t for the local farmers who were willing to experiment with these low-till techniques and adapt them to their local conditions,” said Hobbs. “This is the same group of farmers that launched the Green Revolution,” said Reeves. “They have proven themselves able to adopt improved farming methods faster than any other group of farmers in the world.”
Headquartered near Mexico City, the International Maize and Wheat Improvement Center (CIMMYT) http://www.cimmyt.org is the world’s leading maize and wheat research center, employing more than 100 scientific staff from over 40 nations. CIMMYT scientists work in more than 100 countries and with thousands of scientists and farmers worldwide. CIMMYT is a Future Harvest Center.
Future Harvest http://www.futureharvest.org is a global, nonprofit organization that builds awareness and support for food and environmental research for a world with less poverty, a healthier human family, well-nourished children, and a better environment. Future Harvest is an initiative of 16 food and environmental research centers that receive funding from the Consultative Group on International Agricultural Research http://www.cgiar.org.
The International Rice Research Institute (IRRI) http://www.irri.org is the world’s leading international rice research and training center, which is based in the Philippines with offices in 11 other countries. IRRI focuses 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 a Future Harvest Center.
The Rice-Wheat Consortium for the Indo-Gangetic Plains (RWC) is an alliance of national organizations, CIMMYT, the International Rice Research Institute (IRRI), other international centers, and advanced research institutes that fosters sustainable productivity in rice-wheat farming systems of South Asia http://www.rwc-prism.cgiar.org
Editor’s Note: Photos to support this story are available at http://www.futureharvest.org/news/lowtill.shtml
For further information, contact: Amy Ekola Dye or Ellen Wilson, 301-652-1558, or Coimbra Sirica, 631-757-0673