A field trial of a Genetically-Modified (GM ) banana variety in Uganda has failed to defeat the occurrence of banana diseases. The variety was attacked by Black Sigatoka disease, which can cut a banana tree’s fruit production by half.

Bacterial Wilt hit Uganda in 2001, destroying most plantations and, it is estimated, causing losses of up to $35m (sh57b).

Dr. Andrew Kiggundu, the research team leader, said they were changing strategy to ensure that the GM banana’s resistance would be enhanced.

He told a science reporters' meeting at Shanghai Restaurant in Kampala recently that an anti- Black Sigatoka gene was inserted in parts of the GM banana seedlings to control the disease.

"Depending on where the gene was inserted, it expressed itself inside the crop in a different manner. Our next target will be to see which crop exhibits stronger resistance when the gene is inserted and then we can conduct more experiments," Kiggundu noted.

He explained that Uganda’s GM banana research was still in its infancy. "We are still at a stage where one gene can be introduced. We shall soon acquire dual gene introduction mechanisms," he noted.

The dual gene technology would enable scientists to introduce multiple genes for desired traits in a single variety, before releasing it for farming. Some of the traits include multiple disease and drought resistance, quick maturity and high production.

Black Sigatoka, which is also known as black leaf streak, causes significant reductions in leaf area, yield losses of 50% or more and premature ripening, a serious defect in exported fruit.

It is more damaging and difficult to control than the related yellow Sigatoka disease, and has a wider host range that includes the plantains and dessert and ABB cooking bananas that are usually not affected by yellow Sigatoka.

The high rainfall and humidity of the tropical regions in which bananas are grown are especially favorable for disease development.

The fungus that causes Black Sigatoka is spread from tree to tree by wind, rain and irrigation water.

Kiggundu said Black Sigatoka was endemic in almost all the banana growing areas. It has crippled banana production in the central region around Lake Victoria, eastern region and some parts of the north.

The banana research programme has set up a frontline in Bushenyi district to stop the disease from attacking western Uganda, Kiggundu added. The new banana variety was hoped to help tackle the expense of protecting bananas from this disease.

Black Sigatoka is controlled with frequent applications of fungicides and cultural practices, such as the removal of affected leaves, and adequate spacing of plants and efficient drainage within plantation.

For example, fungicide application includes the use of airplanes or helicopters, permanent landing strips and facilities for mixing and loading the fungicides, and the high recurring expense of the spray materials themselves.

In total, it has been estimated that the costs of control are ultimately responsible for 15-20% of the final retail price of these fruit in the importing countries.

Their great expense makes them essentially unavailable to small-holder farmers, especially prolific in Sub Saharan Africa, who grows this crop. It is these producers who are affected most by this notorious disease.

But despite dismal results from the Uganda study there is hope for the staple fruit. The Bill & Melinda Gates Foundation’s commitment to grant US $74,000 to sponsor a planned pan- African banana conference in Kenya’s coastal city of Mombasa is a blessing for African banana farmers.

The conference, scheduled from 5-9 October 2008, will develop a 10-year research development strategy which aims to stimulate trade and boost the growth of the banana industry across Africa. The gates foundation is joining hands with the International Institute of Tropical Agriculture in partnership with Bioversity International, the Forum for Agricultural Research in Africa, the International Society for Horticultural Science and the Kenyan Agricultural Research Institute.

This will be the first-ever event that links state-of-the-art research to new markets and allow researchers, major industry players and farmers’ groups to exchange ideas.

Bananas, which provide food security, nutrition and livelihood for millions of smallholder farmers, are among the most important food and staple crops in Africa. In the Great Lakes area of East Africa alone, the crop is worth some US$ 1.7 billion annually to 14 million resource-poor farmers.

The watershed event seeks to link research, production, and marketing needs to support banana production and trade growth in Africa. It will also focus on the role of research and the importance of public-private sector partnerships.

The foundation’s package will be used to support the participation of Africa-based farmer groups, cooperatives and entrepreneurs at the conference where they will have the opportunity to present their products and services at stands and booths.

The conference will focus on disease control, seed improvement and the development of local and regional markets of bananas. "The support of the Bill & Melinda Gates Foundation for this conference is a major indication of the importance with which this conference is being viewed for its benefit to Africa," said Dr. Thomas Dubois, Coordinator of the Banana Conference 2008.

"The funding will make attendance possible for up to 50 small farmers and regional entrepreneurs, giving them a chance to showcase their products and services."

The Bill & Melinda Gates Foundation’s Agricultural Development initiative is working with a wide range of partners to provide millions of small farmers in the developing world with tools and opportunities to boost their productivity, increase their incomes, and build better lives for themselves and their families. It invests in efforts across the agricultural value chain - from seeds and soil to farm management and market access. The foundation also supports data collection, research, and policy analysis.

"We are eager to support opportunities to listen to the small scale farmers we are trying to serve," said Dr. Rajiv Shah, Director of Agricultural Development at the Bill & Melinda Gates Foundation. "This conference presents an opportunity for small banana farmers and entrepreneurs to forge links that will support their ability to increase yields and incomes - a critical step so they can lead healthy and productive lives."

About 32% of the African tropical belt considers bananas as the primary source of food.