SSNM works in China

Farmers in China enthusiastically give SSNM the thumbs up.

People say “too much of a good thing is bad,” and this saying holds true often enough, even in science. Take the case of rice farmers in China, who commonly use high rates of nitrogen (N) fertilizer, which is usually not efficiently used by the crop. The excess amount of N fertilizer can actually do more harm than good. It could hurt the environment as it spreads into the atmosphere as greenhouse gas or as nitrate in water bodies. It increases the defenselessness of the crop to lodging and disease and favors survival and reproduction of insect pests, thus encouraging increased pesticide use.

The task at hand
In a study initiated in 2001, Dr. Shaobing Peng and Dr. Roland Buresh of the International Rice Research Institute (IRRI) and their collaborators in China found that site-specific nutrient management (SSNM) achieved comparable or slightly higher rice yields in China than did the traditional farmers’ fertilizer practice (FFP), at the same time saving 30% or more N fertilizer in controlled field experiments. However, the challenge they faced next was how to extend this technology to farmers who had significantly different fertilizer practices.

In 2003 and 2004, the IRRI team, along with Dr. Ruifa Hu of the Center for Chinese Agricultural Policy, Chinese Academy of Sciences, conducted farmer participatory research for on-farm testing of N fertilization using the standard and farmer-modified SSNM for irrigated rice in 2003 and 2004. The study was done in 14 villages in the four major rice-producing provinces of China: Guangdong, Hunan, Hubei, and Jiangsu.

In each year, 12–15 farmers were randomly selected in each study village for a rapid rural technology assessment. The research team discussed with farmers their current fertilizer practice, inputs and outputs, market infrastructure for rice grain, profitability of rice production, cropping system, and the local practices and conditions for rice production.

Based on the assessment, the research team developed a set of suggestions for modifying the SSNM technology to fit the rice varieties in the local village. During an SSNM workshop, researchers and farmers discussed the proposed modifications and finalized the fertilizer application schemes. Farmers then decided whether they were willing to adopt the technologies and participate in the field experiments.

Results are in
Among 514 farmers, 95% were willing to adopt the new technologies of SSNM or modified SSNM, while 76% were willing to conduct experiments using either of the technologies.

More than two-thirds of the farmers preferred adopting the modified SSNM rather than the standard SSNM. Based on farmers’ willingness, 144 farmers were selected to conduct experiments to compare SSNM or modified SSNM with FFP. As compared with FFP, SSNM and modified SSNM increased rice yields slightly by 0.2 ton per hectare using significantly less N fertilizer and no increase in labor input. The rate of applied N fertilizer was reduced by an average of 48 kilograms per hectare using SSNM and 23 kilograms per hectare with modified SSNM.

SSNM VS. FFP. Compared with FFP, SSNM and modified SSNM raised rice yields slightly, using significantly less fertilizer and no increase in labor. (Photo by S. Peng)

The study indicated that farmers are willing to adopt a modified version of SSNM to fit their local rice varieties’ needs. This suggests that new crop management technologies would more likely be successful if they could be modified by farmers themselves according to their specific field conditions.

Dr. Peng’s team sees a huge potential for the spread of SSNM technologies, which would lead to economic benefits for farmers and a positive impact on the environment. The way they see it, everyone, especially the experimenting farmers (early adopters and adapters), technicians, and scientists, has a large role to play in extending these innovative crop management practices.

Shaobing Peng (s.peng@cgiar.org) and Trina Mendoza (t.mendoza@cgiar.org)

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