Ignored for nearly half a century in Asia and Africa, new research - much of it involving farmer groups working in isolated rural areas – is prompting a re-examination of the priority accorded to this important food and forage crop.
Rich in protein and edible oil, groundnut (Arachis hypogaea) is central to the financial and nutritional well-being of hundreds of millions of farmers and consumers across the semi-arid tropics. Nutrition experts point out that groundnut provides over 30 essential nutrients and is an excellent source of niacin, fiber and vitamin E. Rich in anti-oxidants, the crop is naturally free of transfats and contains about 25% protein, a higher proportion than any other true nut.
Increasingly, however, its greatest value is as an income generator. At many locations in West Africa, groundnuts are largely grown by women for the benefit of their families and are used to pay school fees and purchase household essentials. Many of the best improved varieties, some of which are twice as productive as the lines they replaced, were selected by women farmers in Mali and Niger working with national and international plant breeders.
For subsistence farmers who lack the cash to purchase commercial fertilizers, groundnut's nitrogen-fixing capabilities serves as an important soil management tool that contributes both to greater productivity and to the overall resilience of their farming operations.
Origins and general characteristics
Groundnuts first evolved through a chance cross between two wild species. No one knows exactly when or where the cross occurred, but scientists estimate that the two species combined six to eight thousand years ago. Today, there are 79 known wild species, and perhaps a few more undiscovered species still to be collected.
Archeologists have found evidence of groundnut dating back more than 7,000 years. At the time of the Spanish and Portuguese conquest, the crop was widely grown in the West Indies and in South America. By the latter part of the 16th Century it had spread to West Africa through the slave trade.
Groundnut is currently grown on about 21.8 million hectares worldwide, an area similar in size to the United Kingdom. Global production (2011) totaled 38.6 million tons, 95 percent of which occurred in developing countries. Major producers include China, India, Nigeria, USA, and Myanmar. Common names include earthnuts, goober peas, monkey nuts, peanut, pygmy nuts and pig nuts.
Threats to production
Low yields in the semi-arid tropics are attributable mainly to the fact that groundnut is grown in marginal area under rainfed conditions and is subject to periodic drought.
The crop is highly susceptible to contamination by some 20 different mycotoxins, including aflatoxin caused by a fungus Aspergillus flavus. Aflatoxin is extremely hazardous to human health and is especially harmful to the physical and mental development of young children. Over time, exposure to alflatoxin-infected foods can lead to hepatitis, immune system suppression and liver cancer.
The risks associated with aflatoxin contamination have led industrialized countries to establish rigorous quality standards that often deny developing country farmers the opportunity to export. In West Africa, where groundnut is largely produced by women, export prohibitions have important implications for family well-being and frequently prevent farmers from purchasing resources that might otherwise be used to increase productivity.