Yes we (may) have no bananas – impact of bacterial Xanthomonas wilt in Africa

University of Exeter

Researchers: David Studholme, Murray Grant and Julian Smith (FERA)

Funder: National Agricultural Research Organisation of Uganda (NARO)

Research is investigating how bacterium could have jumped from sugarcane to bananas; the project is then creating a genetic enhancement of the banana’s defences, after the disease devastated the livelihoods of millions of people.

The project between University of Exeter and National Agricultural Research Organisation of Uganda (NARO) is addressing questions about Banana Xanthomonas Wilt (BXW).

The project’s long-term objective is to develop resistance to BXW; to do this the team need to first understand the pathology, and then design intervention strategies.

Banana is propagated vegetatively so traditional breeding methods are extremely slow and difficult. No BXW-resistant germplasm has been identified either, so resistance to BXW must be achieved by genetically enhancing the banana’s defences.

The research team being lead by Dr David Studholme and Professor Murray Grant, have used genome sequence data from Xcm and related strains from other crops to reveal the genetic basis of these ‘host-jumps’.

The research data can also be used to develop and validate diagnostics to measure genetic plasticity of Xcm populations and detect newly emerging virulent lineages.

Bananas and plantains are major food staples and cash crops in the East African Great Lakes zone. In the last decade the BXW was first identified on Enset, a plant related to the banana, in Ethiopia in the 1960s, and discovered on Ugandan bananas in 2001. It has since spread into neighbouring Kenya, DR Congo, Rwanda and Burundi and Tanzania (2007).

BXW can become epidemic within weeks, leading to complete crop loss. Many families have abandoned banana cultivation, which has caused unsustainable increases in food price.