Foliage of potato plants grown in aeroponics in a greenhouse at CIP-Huancayo, Peru. In aeroponics there is greater foliage growth than in traditional methods. Photo by Victor Otazu of CIP-Huancayo.
With the world wide population expected to grow at a rate of 100 million people each year for the next twenty years, mainly in developing countries, issues surrounding food security and availability will gain an unprecedented importance. For countries like Kenya, where the Kenya Red Cross estimates over 10 million people are food insecure, the potato could be the solution. Though the potato was introduced to East Africa as far back as the 1880s, it is only over the last thirty years that it has become a staple as both a food crop, second only to maize, and as a source of income, with more than 2.5 million people employed in potato farming activities. Even still, potato production is stagnant in Kenya: around 800,000 tonnes were harvested in 2007 and around 25 kg consumed per capita, compared to Malawi, sub-Saharan Africa’s largest potato producer, with 2,200,000 tonnes harvested in 2007 and around 88 kg consumed per capita.
Recently, there has been a government-backed push in Kenya to promote the potato as both a food security crop and a cash crop. The International Potato Center (known by its Spanish acronym CIP and based in La Molina, Lima, Peru) has partnered with the government of Kenya to promote the potato as a strategic crop. With a team of scientists from 25 countries, CIP seeks to reduce poverty and achieve food security on a sustainable basis in developing countries through scientific research and related activities on the potato, sweet potato, other root and tuber crops, and on the improved management of natural resources in the Andes and other mountain areas. CIP’s regional headquarters in Sub-Saharan Africa are located in Nairobi, Kenya and CIP scientists are also based in Uganda, Malawi, Mozambique, Angola, and Benin. Their efforts in this region focus on research for development to combat vitamin A deficiency through sweet potatoes and to combat poverty and food insecurity utilizing late-blight resistant potato varieties. CIP and the government of Kenya hope to boost potato production threefold by 2012 and help achieve food security as well as create a greater source of revenue for its people.
Kenyan farmer plowing his field with oxen
The potato, rich in carbohydrates, protein, calcium and important minerals and vitamins, including Vitamin C, is the world’s most important root and tuber crop and the third most important food crop, after wheat and rice. Potato is cultivated in more than 130 countries, with consumption steadily growing in developing countries like China and India, making it the third most important food security crop in the world.
The United Nations may have designated 2008 the International Year of the Potato, but researchers are still hard at work trying to make this crop more available in countries with low food stability. Though the potato is regarded as a fairly adaptable plant, it is subject to a number of pests and diseases, most notably late blight that tragically wiped out Ireland’s potato crops from 1845-1848 and led to a famine that resulted in the deaths of one million people. Quality potato seed can also be hard to come by in the developing world. The same systems that provide seed multiplication and certification in Europe and North America have been difficult to re-create in Africa because of a lack of infrastructure. As a result, there is only a small amount of quality seed available, which is very expensive. This forces farmers to then plant potatoes from the year’s previous crop, many of which suffer from a build-up of disease, creating a cycle of food instability. Therefore, scientists are working on developing accessible, blight-resistant high-grade potato seed in an effort to harness the benefits of this crop to combat hunger and create a source of revenue for farmers.
The potato is relatively drought-resistant, making it especially attractive for this area. Ian Barker, head of the Virology Unit at CIP, explains: ÛÏA tuber crop will always yield something, whereas a grain crop may fail completely under drought or semi-drought.Û According to the World Food Programme, the impact of the recent four-year drought on staple food crops like maize is expected to yield 25% less this year than the four-year average. This makes the hardy potato seem like the perfect solution for a country frequently on the brink of famine.
According to CIP, Kenya’s potato fields have remained stagnant over the past decade due to factors such as price hikes, climate change, and policy deficiencies as well as farmers’ use of poor quality seed and improper post-harvest practices. But now may be the perfect time to turn to the potato. Barker explains: ÛÏIt is certainly true that potato is an attractive smallholder crop because it acts both as a food security crop as well as an income-generating crop. The rapid rise in urbanization of populations in Africa is increasing the demand for potato and thus increasing opportunities for smallholders to gain income.Û
Minitubers of the Canchan cultivar in the first aeroponic module installed at CIP-Huancayo, Peru in 2006. Photo by Victor Otazu of CIP-Huancayo.
The new efforts seek to improve potato production from multiple angles, ranging from public policy to better seed production and increased resistance to potato disease. Barker has been working to facilitate access to clean quality seed for use by smallholder farmers: ÛÏThe lack of affordable quality seed remains a key constraint in holding back potato yields in Kenya. More specifically we work with the producers, both public and private, of high-grade seed or basic seed to increase the availability of this material.Û
CIP is also working with private and public sector partners to introduce a new technology that produces substantially higher numbers of potato seed, or the mini-tubers from which new potatoes are grown, and helps to ensure that they are disease free. The technology is known as aeroponics, and involves growing seed tubers hanging in mid-air without the use of soil, with much higher multiplication rates than conventional methods. It increases the availability of clean seed while lowering the cost to smallholder farmers.
As Barker explains, ÛÏIts importance is that it increases the multiplication rate of the potato crop from perhaps 5 to 1 to potentially 50 to 1. This means we can produce high quality seed much faster and reduce the number of multiplication cycles in the field, where the crop picks up diseases, needed before we have sufficient seed to give to smallholders.Û CIP has been running aeroponics in Kenya for two years with both public and private partners. They distributed their first high grade seed to seed multipliers this year and expect clean seed to be available to smallholder farmers beginning in March of 2010.
In close collaboration with the Kenya Agricultural Research Institute (KARI), CIP is also working to test and release varieties of potatoes for smallholder farmers that are resistant to late blight, the most serious disease threatening potatoes worldwide. Late blight is caused by the fungus-like oomycete, Phytophthora infestans, and spreads through spores transported in the wind or the use of infected tubers. Though the disasterous effects of late blight, which led to the Irish Potato Famine, may sound like a problem of the past, it still remains the most destructive food crop disease in the world, causing as much as $10-20 billion in annual losses. For now, a heavy reliance on fungicides is the most effective defense against late blight, but the hazards to human and environmental health make this a poor trade-off.
Yield of a native potato, Uqui nawi, showing the potential of potato seed production in aeroponics. The cost of each clean minituber is around $ 0.20. With aeroponics this cost can be reduced by å_ or even more. Photo taken at CIP-Huancayo, Peru by Victor Otazu.
CIP coordinated a meeting held in Bellagio, Italy in November 2009, gathering twenty-nine scientists from twenty-one different countries to discuss the management of late blight and coordinate a global strategy to combat this growing scourge. Greg Forbes, a plant pathologist at the International Potato Center and organizer of the meeting, explains: ÛÏLate blight can get worse because the climate becomes more favorable for the disease or because there are changes in the pathogen population. Since aggressive strains of the pathogen are still spreading, we expect the disease to continue getting worse. We also predict that climate change will make the disease worse in some developing countries.Û
Forbes maintains that the most effective way of controlling the spread of late blight is through host plant resistance, but it can be difficult to get these plants into the hands of farmers who need them. And even when they do, the use of toxic fungicide is still needed: ÛÏThe correct use of fungicides is complex and for this reason we consider that late blight is a knowledge-intensive problem. We have also worked on improving training materials and training procedures to help farmers build capacity to manage the disease. The problem here is that training large numbers of farmers is time consuming and costly.Û
Says Forbes: ÛÏIn the end, a global strategy will require financial support and this in turn requires us to have late blight on the policy agenda of donors. We need to have more input from national governments about the negative impacts of this disease to entice donors to support a global research agenda.Û
Sources
Peter T. Ewell1 ÛÏOverview of CIP Work in Sub-Saharan Africa Potato and Sweet potato in Africa: Research in Partnership with National Institutions, Other ActivitiesÛ International Potato Center, La Molina, Lima, Peru
www.cipotato.org International Potato Center
www.potato2008.org UN’s official website for International Year of the Potato
www.kari.org Kenya Agricultural Research Institute
www.wfp.org World Food Program
www.kenyaredcross.org Kenya Red Cross