International Fertilizer Development Center

A new agricultural technology that cuts nitrogen fertilizer waste in half while increasing rice yields is spreading quickly in Bangladesh and is being investigated by 15 other nations, including more than a dozen in sub-Saharan Africa.

Chemical fertilizers are critical to raising crop yields, but their cost has been prohibitive for many subsistence farmers, particularly those in Africa.

The inefficiency of fertilizer application is also a major problem. By some estimates, as much as 70 percent of nitrogen fertilizer applied to crops in developing nations is lost to runoff or released into the atmosphere, contributing to coastal “dead zones,” global warming, ozone layer depletion and other problems.

The new technology is fairly simple. Rather than applying urea, a nitrogen fertilizer, to the soil surface in tiny granules, the urea is compacted into briquettes and placed several inches below ground.

These briquettes release nitrogen slowly, dramatically reducing the amount of fertilizer washed away by rain or absorbed by the air. The technique has raised rice yields while limiting the amount of the nitrogen available to weeds, curbing herbicide use.

“The farmers are using nearly 40 percent less urea, and yet they are producing nearly 20 percent more rice,” said Amit Roy, the president of the International Fertilizer Development Center, a nonprofit research group that helped develop the technology, known as “urea deep placement.”

The use of urea briquettes in Bangladesh began in earnest in 2007, when rising global energy and commodity prices caused the price of chemical fertilizers to nearly triple in the space of a year.

Since then, Bangladeshi farmers have put 1.7 million acres under cultivation using the technology, and according to Mr. Roy, the Bangladeshi government has plans to expand its use to more than 12 million acres in the next several years.

“They want to take it all over the country,” he said.

The success in Bangladesh has generated interest internationally, particularly among nations in sub-Saharan Africa where fertilizer use has long been cost-prohibitive for subsistence farmers. So far, four delegations from Africa — with representatives from Malawi, Uganda, Nigeria, Togo, Mali, Burkina Faso, Niger, Madagascar, Senegal, Rwanda, Burundi, Congo and Kenya — have visited Bangladeshi farms and briquette factories.

Several trials in Africa – as well as in Laos and Vietnam – are underway.

“So far the results of the trials in Africa have been very encouraging and there is discussion about taking this technology to scale in several West African countries,” Mr. Roy said.

Whether urea deep placement will prove attractive to countries like China, which use – and waste – vast amounts of nitrogen fertilizer, is unclear, however. At present, the application of the briquettes is labor intensive, making it best suited to small, unmechanized farms, Mr. Roy said. Yet work is under way to adapt the principles behind the technology for use on large industrialized farms.