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NERICA- New Rice
Transforming agriculture for West Africa

Guy Manners, WARDA, Ivory Coast

Most of the 20 million rice farmers in West Africa are bound to an environmentally degrading slash-and-burn farming system. Asian rice species which entered Africa 450 years ago can't compete with the weeds, so after a crop or two it's time to clear more land. Planting the traditional African rice species is not worthwhile for farmers as it simply does not produce enough rice. Scientists have now come up with the technology to produce NERICA, a new grain of rice set to improve the lot of West African rice farmers.


Nerica, new garin of rice transforming agriculture in West  AfricaA new rice variety is transforming agriculture in a large portion of West Africa, benefiting twenty million farmers- mostly women- and helping reduce the high rice import bills. Labelled NERICA for "New Rice for Africa", the new variety combines the ruggedness of local African rice species with the high productivity traits of the Asian rice that was the mainstay of the Green Revolution.

Rice now contributes more calories and protein than any other cereal in humid West Africa, and about the same as all roots and tubers combined.

Demand for rice is growing faster in this region than anywhere else in the world. In the last three decades, rice imports have uncreased eight-fold to over 3 million tonnes a year at a cost of almost US$ 1 billion.

Overcame Failures

In 1991, a biotechnology-based programme was initiated to combine the best traits of the Asian and African rices. Vital to the effort were gene banks that contain seeds of 1500 African rices - which had faced extinction as farmers abandoned them for higher yielding Asian varieties. The rapid advances in agricultural science enabled the development of NERICA. Scientists at the West Africa Rice Development Association (WARDA) overcame a series of disappointing failures when they succeeded in crossing two species using embryo rescue techniques.

Genetic differences in the two species made breeding difficult but also gave the new rices high levels of heterosis; this is the phenomenon in which the progeny of two genetically different parents grows faster, yields more, or resists stresses better than either parent.

The new rice smothers grain-robbing weeds like it's African parents, resists droughts and pests, and is able to thrive in poor soils. The trait of higher productivity conferred by it's Asian parents is also present, meaning that with few additional inputs the farmers using NERICA rice can double production and raise incomes. It is helping to meet multiple needs - food, nutrition and income - for millions of people in the humid tropics of West Africa. 

The panicles of this rice variety can hold 400 grains compared to the 75-100 grains of it's African parents. Further improvements in the plants architecture such as longer panicles with forked branches, strong stems and panicles that hold grain tightly and prevent shattering- will allow the new varieties to out yield others and produce bountiful harvests with modest fertilisation. They mature 30-50 days earlier than traditional varieties allowing farmers to grow extra crops of vegetables or legumes. They are taller thus making harvesting easier and they grow better on the fertile, acid soils that comprise 70% of the upland rice area in the region. In addition, there is 2% more body building protein in these new varieties than either their African or Asian parents.

Valuable Feedback

Participatory research is at the heart of the NERICA success story. A symbolic relationship between scientists and farmers was a key ingredient. Through a mechanism called Participatory Varietal Selection, farmers grew several varieties and provided valuable feedback to the scientists. In turn, the scientists were able to learn about the traits that were of most value to the farmers and then incorporate those preferences in the breeding strategies.

More than 1300 farmers participated in the 1998 programme to start growing the new rice varieties in Guinea. This was followed by a 1999 project to increase seed supply at national level and a farmer awareness campaign. Average farm yields are increasing from about one to more than one and a half tonnes per hectare with low inputs - and at least double that with good management and intermediate inputs. It is projected that farmers will grow these new rice varieties on almost 330 000 hectares by 2002.

Several new varieties, yielding at least a quarter more than the traditional varieties will be released. Research shows that 10% adoption in just three countries, Guinea, Cote d'Ivoire and Sierra Leone - will return an extra US$ 8 million to farmers annually. Adoption by 25% of farmers will return US$20 million.

A number of international agricultural research institutions were partners with WARDA in the effort plus a broad range of stakeholders from farmers to national agricultural research programmes in 17 African countries.

For further information contact:

E-mail: Guy Manners  Information Officer, WARDA, Ivory Coast.

This article was provided by AgriForum, Quarterly Newsletter of the Association for Strengthening Agricultural  Research in Eastern and Central Africa.

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