food • The Best of Africa

Save the humble plantain

by: admin - May 2nd, 2008 Filed under: Food & Drinks Add Comment

A tiny pest threatening the staple diet of millions in Africa could soon be eradicated in a project announced today, bringing together plant experts from Leeds and Uganda.

Professor Howard Atkinson and Dr Peter Urwin from the University of Leeds’ Faculty of Biological Sciences have been awarded £500,000 through the £7 million Sustainable Agriculture Research for International Development (SARID) scheme launched today by the Department for International Development (DFID) and the Biotechnology and Biological Sciences Research Council (BBSRC). The Leeds project is one of 12 funded under the scheme, all of which involve unique partnerships between UK scientists and researchers from institutions in Africa, Asia and elsewhere.

Plantain and other varieties of cooking banana provide 30 per cent of the daily calorific intake of Ugandans and many of Africa’s other poorest populations. But up to half of the plantain harvest is lost through nematode worms feeding on and damaging their roots. The Leeds researchers will work with colleagues from the International Institute of Tropical Agriculture in Uganda to find a solution to the problem.

The partnership will use the latest biotechnology techniques to develop pest resistance in plantains, which can then be made available to growers throughout Africa. A major part of the 3-year project is ensuring that the new resistant plantains can be produced across Africa – where growing conditions can vary enormously.

Professor Atkinson says: “The impact of this parasite can be overwhelming for families and communities that rely on plantain for their staple diet. Already nearly one third of the sub-Saharan African population is severely undernourished, so poor crop yields or worse – crop failure – can be catastrophic for subsistence farmers.”

“If we can make these crops more reliable through resistance to the nematode, not only will it secure dietary intake, but some land will also be freed up for nutritious crops like beans – and surplus plantains could be sold at market to give some income to the poorest of communities,” he says.

However, like the sweet dessert bananas we are more familiar with, plantains are sterile plants that produce no seeds, limiting the use of conventional plant breeding to build resistance to the pest over successive generations.

Professor Atkinson says: “It makes the job tougher. Plantains are re-planted using offshoots. This means that every plant is a genetically identical clone of the original – and a pest that affects plantains is capable of affecting every single plant.”

“There are four or five types of problematic worm that live in the soil and we’re looking to find a way to control them in a ‘one size fits all’ approach. Our Ugandan partners have developed a technology to add genes into plantains and this, combined with our leading knowledge of nematodes, makes us hopeful that we can target this technique to inhibit the unique digestive process of the worms and stop their destruction, without affecting surrounding plants or other animals in the soil.“

We love our PLANTAIN!

Tags: food

Yam bean a nearly forgotten crop

by: admin - May 2nd, 2008 Filed under: Food & Drinks Add Comment

The Yam bean originated where the Andes meet the Amazon and is locally grown in South and Central America, South Asia, East Asia and the Pacific. It is produced in three species which are called the Amazonian, Mexican and Andean. Interbreeding of the bean has resulted in fertile and stable hybrids. This gives it potential to be reclassified as a single species, provide high quality food production and offer a sustainable cropping system that has been needed in Africa.

Researchers believe they have discovered a protein-rich starch staple in the yam bean in Peru. They were previously considered a root vegetable due to the high water content; however this ‘Chuin’ type has lower water content. Families living in the area have been producing it as flour. The crop has extremely high seed production, but its seeds contain high concentrations of rotenone. This toxic compound has been used for reducing fish populations and parasitic mites on poultry. Seeds are never consumed since they are mildly toxic to humans and other mammals. If the rotenone was removed from the seeds, they could provide a strong protein source as well as seed oil profitable in the food industry.

Séraphin Zanklan, a scientist at Centre Songhai in Porto-Novo (Benin), has investigated the yam bean for its potential to grow and produce food under West African conditions. The study was funded by a scholarship from the German Academic Exchange Service (DAAD). Thirty-four yam genotypes were grown with and without flower removal at one droughty location and one irrigated location. Of the 33 traits that were measured, nearly all showed large genetic variation. This and the easy spreading of its seeds, make the crops very desirable to breeders. Results from the study will be published in the July-August 2007 issue of Crop Science.

The study identified genotypes with high storage root production. Flower removal increased storage root production by 50 to 100%. Several yam bean genotypes showed very low reduction in storage root and seed production under drought stressed conditions. As expected, the storage roots did show high protein and starch contents. They have as much as three to five times more protein than potatoes or yams. Most importantly, it was found that storage roots can be processed into ‘yam bean gari.’ This is similar to the current staple of West Africa, ‘cassava gari,’ a granular flour.

The bean could make a significant contribution to the improvement of food support, especially where resources are poor. The research is ongoing at the International Potato Center, which has a mandate for the bean in the frame of Andean Root and Tuber Crops. Further evaluation is needed on the range of yam bean variations under different conditions. More information on where they can be grown, their agronomic potential and genetic diversity is important to determine the types of breeding programs necessary for yam beans.
###

Crop Science, http://crop.scijournals.org/ is a peer-reviewed, international journal of crop science published bimonthly by the Crop Science Society of America.
ASA www.agronomy.org, CSSA www.crops.org and SSSA www.soils.org are educational organizations helping their 11,000+ members advance the disciplines and practices of agronomy, crop, and soil sciences by supporting professional development and science policy initiatives, and by providing quality, research-based publications, and a variety of member services

Tags: food, yam

Rooibos

by: admin - April 28th, 2008 Filed under: Food & Drinks Add Comment

Rooibos, (pronounced /ˈrɔɪbɒs/, like “roy-boss”), Afrikaans for “red bush”; scientific name Aspalathus linearis) is a broom-like member of the legume family of plants and is used to make a tisane (herbal tea). Commonly called South African red tea or simply red tea or bush tea, the product has been popular in South Africa for generations and is now consumed in many countries. It is sometimes spelled rooibosch in accordance with the Dutch etymology, but “roy-boss” remains the correct pronunciation.

Rooibos is becoming more popular in Western countries particularly among health-conscious consumers, due to its high level of antioxidants such as aspalathin and nothofagin, its lack of caffeine, and its low tannin levels compared to fully oxidized black tea or unoxidized green tea leaves. “Green” rooibos (see above) has a higher antioxidant capacity than fully oxidised rooibos.

Although rooibos was first reported in 1772 by botanist Carl Thunberg, the Khoisan people of the area had been using it for a long time[citation needed] and were aware of its medicinal value[2]p. 52. The Dutch settlers to the Cape adopted rooibos as an alternative to black tea, an expensive commodity for the settlers who relied on supply ships from Europe. Until the 19th century, however, Dutch usage of the tea was minimal.

In 1903, Benjamin Ginsberg, a Russian settler to the Cape and descendant of a famous tea family, saw potential in rooibos and began trading with the local Khoisan people who were harvesting it. He sold his “Mountain Tea” to settlers in the Cape and shortly became the first exporter of rooibos using contacts from the family tea business.

In the 1930s, Ginsberg convinced a local doctor and Rhodes scholar, Dr. Peter Nortier to experiment with cultivation of the plant. Dr. Nortier cultivated the first plants at Clanwilliam on the Klein Kliphuis farm, owned by W.T. Riordan, a retired magistrate. The tiny seeds were difficult to obtain, as they dispersed as soon as the pods cracked, and would not germinate without scarifying. Dr. Nortier paid farmers to collect seeds. An aged Khoi woman had found a rather unusual source of supply. She came again and again, receiving a shilling for each matchbox filled with seed. She had chanced upon ants dragging seed one day, followed them back to their nest and, on breaking it open, found a granary. The attempts by Dr. Nortier were ultimately successful, which led Ginsberg to encourage local farmers to cultivate the plant in the hope that it would become a profitable venture. Klein Kliphuis became a tea farm, and within ten years the price of seeds soared to an astounding £80 a pound, the most expensive vegetable seed in the world. Today the seed is gathered by special sifting processes, and Klein Kliphuis is now a guest farm.

Since then, rooibos has grown in popularity in South Africa, and has gained considerable momentum in the worldwide market too. A growing number of brand-name tea companies sell this tea, either by itself or as a component in an ever-growing variety of blends.

The popularity of rooibos has also gained from its association with Precious Ramotswe, the Tswana detective in Alexander McCall Smith’s series of novels about The No. 1 Ladies’ Detective Agency. Mma Ramotswe’s favourite drink is red bush tea (rooibos), which she often promotes as a therapeutic drink to her friends and clients – and hence the readers of the books.