Searching for resistance to Fusarium tropical race 4 in African cultivars

Inge Van den Bergh Sunday, 02 May 2010

A new project, based on a recommendation made at the latest ISHS/ProMusa Symposium, will help predict the impact of the dreaded Fusarium strain on banana production in Africa.

East African Highland bananas are a major
staple in the Great Lakes region. (A. Vezina)

As a secondary center of Musa diversity, Africa has cultivars that are unique to the continent, such as the East African highland bananas (EAHB). African farmers have also selected for a diversity of Plantains unmatched anywhere else. But because these cultivars are not exposed to the so-called tropical race 4 (TR4), which is currently restricted to Asia, it is not known how they would react to this particular strain of the soil-borne fungus that causes Fusarium wilt.

In trials funded by the Global Crop Diversity Trust, 7 EAHB and 7 Plantain cultivars representative of the genetic diversity of their respective groups will be evaluated for their host reaction to TR4 in China and Indonesia. The plants used in the trials will come from the International Transit Centre.

Both groups of cultivars are resistant to races 1 and 2 of Fusarium wilt, but the genetic make-up of the EAHB cultivars (they belong to the same genome group as the Cavendish cultivars) suggests that they might be vulnerable to the TR4 strain. Unconfirmed reports point in the same direction for Plantains. If this is confirmed and little to no variation is observed among the accessions tested, the impact of TR4 on food security in many regions of Africa could be devastating. On the other hand, the early identification of sources of resistance would help prepare African producers for what most experts think is the inevitable arrival of the strain on the continent.

The project is coordinated by Bioversity International in partnership with Stellenbosch University in South Africa, the Guangdong Academy of Agricultural Sciences in China and the Indonesian Tropical Fruit Research Institute in Indonesia.

For more information, contact Gus Molina.