Low till agriculture takes off in Asia

Posted: 19 October 2001

The trend towards low till agriculture is sweeping across Asia, increasing harvests, reducing water use by as much as 30 to 50 percent, and requiring less fuel for running tractors on farms, report scientists from the International Maize and Wheat Improvement Center (CIMMYT).

In warmer areas in particular, where the topsoil layer is thin, conventional tillage contributes to soil loss and land degradation. Low till farming does away with intensive and repeated ploughing of fields and 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.

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 across Asia and a three year drought in Pakistan threaten the region's rice and wheat yields.

"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.

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. "South Asia is facing an extreme crisis in water - the lifeblood of this region - and that could be absolutely devastating," said Dr Peter Hobbs, a natural resource agronomist with CIMMYT. "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." 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 more than 100,000 hectares in 2000-2001.

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 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."

At the World Congress on Conservation Agriculture in Madrid in October (2001), the UN Food and Agricultural Organisation (FAO) said moving to conservation agricultural could save millions of hectares of agricultural land from degradation and erosion.

Applying conservation agriculture means that farmers drastically reduce tillage and keep a protective soil cover of leaves, stems and stalks from the previous crop. This cover shields the soil surface from heat, wind and rain, keeps the soils cooler and reduces moisture losses by evaporation.

Soil tillage is also the single most energy consuming and air polluting operation among all farming activities. By not tilling the soil, farmers can save between 30 and 40 per cent of time, labour and fuel costs compared to conventional cropping, reports FAO. Because there are upto two-thirds fewer weeds on low till farms, herbicide use is also reduced.

Globally, conservation agricuture is now being practised on about 58 million hectares of land, from the tropics to the Arctic Circle. In many areas it has been observed after some years of conservation farming, natural springs that had disappeared started to flow again. Water filters easily through soils under conservation agriculture, increasing the groundwater level, reducing surface runoff and thus soil erosion.

"Conservation Agriculture reaches yields comparable with modern intensive agriculture but in a sustainable way," the FAO stressed. "Yields tend to increase over the years with yield variations decreasing."

Source: Environment News Service, October 2001

Links:

World Congress on Conservation Agriculture

International Maize and Wheat Improvement Center (CIMMYT)

International Rice Research Institute

Future Harvest