Overview of outcomes and impacts

Rice is the staple food in Asia, where 90% of the world’s rice is grown and consumed. To produce sufficient rice to meet the calorie requirements of the poor, farmers must apply nutrients in the form of fertilizer. However, poor farmers often lack knowledge on the most effective management of nutrient inputs for rice. Research led to the development and dissemination of simple technologies to enable poor rice farmers in Asia to increase their production and profits through more efficient use of fertilizer.

Activities and scope of the project

Many of the nutrients required by a rice plant for its growth come from the soil, but this supply is insufficient to produce the high yields required to feed the population in Asia. Nutrients in the form of fertilizer must be applied to supply the additional need of the rice plant. Farmers typically lack knowledge on the most effective use of fertilizer for their fields, and their ineffective use of fertilizer leads to diseases of the rice plant, damage to the environment, and low profit from farming. Research funded by the Swiss Agency for Development and Cooperation was conducted in the fields of rice farmers throughout Asia to develop an improved approach of nutrient management for rice. A pre-project survey in Vietnam provided an indication of the size of the problem: 33% of the farmers were using insufficient fertilizer, 33% were using about the right amount, and 33% were using too much.

Goal of the study

The goal was to develop and disseminate improved integrated nutrient and pest management practices for poor Asian rice farmers in order to increase the profitability of rice farming while ensuring a sufficient supply of affordable rice for the urban poor.

The focus was on providing technologies to farmers for use in their own fields (site-specific nutrient management), thereby enabling farmers to optimally “feed” their rice crops with supplemental nutrients for higher profit while protecting the environment from an unbalanced use of fertilizer and reducing the need for pesticides to control rice diseases and insects.

Target group

The study was aimed at poor farmers in lowland intensive rice-producing regions. Research and extension activities have been conducted in Bangladesh, China, India, Indonesia, Myanmar, the Philippines, Thailand, and Vietnam.

Results and effectiveness

·      Research led to the development of an improved approach of site-specific nutrient management for rice, which provides poor rice farmers with simple guidelines for “feeding” rice plants with supplemental nutrients as and when needed for optimal profit while protecting the environment.

·      Research in the fields has shown that effective timing and rates of application of fertilizer resulted in large increases in yield over the traditional farmers’ practice. For example, in northern Vietnam, yield increased by as much as 15% during the high-yielding season and by as much as 8% in the low-yielding season, which resulted in a net benefit of US$150 per hectare per year for two crops. In Bangladesh, yield increases from improved nitrogen management alone increased net returns by about $50 per hectare per season, and net returns increased by as much as $150 per hectare per season when management of other nutrients was also improved.

·      Site-specific management tools were developed, enabling farmers to make informed decisions on how to apply fertilizer effectively on their crops. In effect, a plant-based approach for “feeding” rice with nutrients was developed.

·      Research showed that improved nutrient management for rice resulted in more sustainable and environmentally benign cropping systems. The more efficient use of nitrogen fertilizer reduces the emission of greenhouse gases to the atmosphere and hence lowers the global warming potential per unit of rice produced. The improved nutrient management reduced the susceptibility of the rice plant to diseases and insect pests, thereby reducing the need for pesticides.

·      Tools to success
(i) Recommendations were developed as to when farmers apply nitrogen, phosphorus, and potassium fertilizers and how much. For example, only a moderate amount of nitrogen fertilizer is recommended within the first 14–21 days of their crop when the crop is not hungry for nitrogen; subsequent applications of nitrogen are based on need as indicated by leaf color. Sufficient applications of phosphorus and potassium fertilizers are recommended to overcome deficiency and replace nutrients removed with the harvest to maintain soil fertility. The timing of fertilizer applications is based on critical stages of the crop when a particular nutrient is most needed. A schedule of fertilizer applications is made for each location, depending on climate, rice cultivar, and soil nutrient status. Fertilizer rates are also adjusted depending on farmers’ ability to buy fertilizer.

    (ii) A simple, low-cost leaf color chart with a standardized color formulation was developed and disseminated to rice farmers in Asia. The leaf color chart is a plastic ruler about 13 centimeters long with four color panels ranging from yellow green to dark green. It enables farmers to determine the need of their rice crop for nitrogen by checking the color of a rice leaf against four color panels (see photo) Farmers can then apply nitrogen-based fertilizer as and when needed by the plant. The leaf color charts cost only $0.30 and can be used for many years. Guidelines for improved nutrient management, including the use of the leaf color chart, were developed for the principal rice-growing regions in eight Asian countries.

(iii) Extension materials on how to use the leaf color chart and local recommendations on the timing of fertilizer use have been produced in local languages. During 2004 and 2005, more than 200,000 leaf color charts were distributed to farmers in Asia.

Training

From 2001 to 2004, more than 250 training courses for local extension officers and about 450 training courses for farmers have been conducted in Asia. An estimated 35,000 farmers, extension workers, and government officials have participated in field days and field visits.

Adoption and policy impact

Annual net benefits to farmers have been assessed in three countries. In southern India, farmers who followed the recommended practices increased their annual income by US$168 (47% increase in income); in the Philippines, farmers got an extra US$140 (13% increase); and, in southern Vietnam, farmers got an extra US$34 (4% increase) (see table).

The national integrated pest management (IPM) program in Vietnam has incorporated nutrient management based on the site-specific nutrient management approach into the curriculum for farmer field schools, and 50,000 leaf color charts are being distributed through these schools to groups of farmers in Vietnam. Through this approach, more than 50,000 farmers will be exposed to and trained in improved nutrient management.

In Bangladesh, the national extension system has already distributed to poor rice farmers more than 50,000 leaf color charts in 2004 and 2005, with guidelines on improved nutrient management for rice. An effort to reach more farmers and to enhance the training for extension workers and farmers is planned for 2006.

In China, the site-specific nutrient management approach for rice has been evaluated and demonstrated in five provinces, which represent 40% of the total rice-growing lands in the country. In 2005, the local governments in these provinces started promoting improved site-specific nutrient management technology for rice as part of their local extension initiatives. In Hunan Province, a major rice-growing area in China, the local extension system in about 50% of the counties (local government units) in the province started promoting and demonstrating the technology to rice farmers in 2005.

Fertilizer companies in Asia have also started adopting the new site-specific nutrient management approach in their promotion and demonstrations with rice farmers. One company in the Philippines, for example, is distributing 5,000 leaf color charts to rice farmers, together with literature and training on the improved management of nutrients for rice.

Good nutrient management also reduces impacts of pests and diseases

Annual net benefits^a accruing from recommended nutrient management (site-specific nutrient management) and traditional farmers' use of fertilizer.^b

^aNet benefit = Gross revenue – total input cost.  ^bDetermined through focus-group discussions (two rice crops, 2002-03).

Farmers can assess how much N their rice crop needs by comparing the color of their growing crop with standardized colors. (Photo from IRRI)

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