Research News

Coffee wilt disease was first reported from Central Africa in the 1920s, but was brought under control by the 1950s and was no longer considered a threat. However, it returned with a vengeance in the 1990s, taking advantage of coffee institutes weakened by years of political and economic crises.

CABI has recently published the final report of a seven-year study on coffee wilt disease funded by the Common Fund for Commodities, together with the EU and DFID. The report was presented at the Common Fund for Commodities’ 20th Anniversary Seminar in The Hague in December 2009.

The research programme involved scientists from UK, France, Belgium and seven African countries including the four countries where the disease is now present: Democratic Republic of the Congo, Uganda, Tanzania and Ethiopia.

The disease is caused by a fungus (Fusarium xylarioides), although genetic studies carried out during the project suggest that there are at least two separate forms, one attacking only Robusta coffee, the other (found in Ethiopia alone) attacking Arabica coffee.

Unlike other coffee diseases, this one kills the plant, causing total 100% farm losses which impact smallholder farmers severely - especially since the soil remains infective for many months. The most affected countries have been DRC and Uganda where total losses to the disease exceed US$500 million. Total losses caused by the disease in the four affected countries over the last 10 years are hard to assess, but are conservatively estimated to exceed US$1 billion in lost earnings to farmers. As such it represents the largest single natural disaster ever to affect African coffee.

The project supported a range of activities to develop protective measures for the disease, including the development of resistant Robusta clones, carried out by Ugandan scientists of the Coffee Research Institute at Kituza, which will be released to farmers in 2010. This is a major achievement by those scientists, who have developed and multiplied the clones in a very short time.

Thousands of extensionists and more than one million farmers were trained during the course of the project to recognize the symptoms of the disease and take early action to prevent spread.

Despite the project’s advances, much more needs to be done, since the disease is still spreading in DRC potentially threatening West African coffee countries. Arabica coffee is also at risk if the disease were to spread southwards from Ethiopia to Kenya and beyond.

More information

• Full report: A synthesis of the work of the Regional Coffee Wilt Programme 2000–2007. Coffee Wilt Disease in Africa
• See the DFID-funded project 'Epidemiology and variability of Gibberella xylarioides, the coffee wilt pathogen' conducted as part of the Crop Protection Programme, and read the final technical report
• Project information on the CABI website.
• Read the SciDev.net article - Fight against coffee disease gathers strength