Protecting global food production and woodland environments

Wheat stem rust (Credit: Yue Jin, ARS, US Dept of Agriculture)

Models developed and tested by the Epidemiology and Modelling Group at the University of Cambridge, led by Chris Gilligan, have been used to inform government policy and practical implementation of surveillance and control methods for major epidemic diseases of crop plants and natural vegetation.

The research was motivated by the need for an epidemiological toolkit to mitigate the impact of emerging epidemics that threaten crop plants and food security, as well as natural vegetation such as forest and woodland trees. The toolkit enables rapid and effective deployment to predict the rate of disease spread and cost-effective intervention options as epidemics occur in real time.

The models incorporate data on crops, environment, pest/vectors and grower activity, and have been implemented in different contexts to generate positive impacts on the management of damaging plant diseases.

Among the impacts, use of the models to forecast wheat rust disease has enabled up to 500,000 smallholder farmers in Ethiopia to take timely preventative action; informed strategy for the control of banana bunchy top virus for the Australian banana industry, which is worth Aus $605 million to the country’s economy; and informed surveillance and management of tree diseases including ash dieback, ramorum disease of larch and oak processionary moth in the UK, and citrus greening in California, USA.

The models have also been used for predicting the spread of and control options for cassava brown streak virus in ten countries in sub-Saharan Africa, leading to governmental policy changes. Cassava is a staple food crop for an estimated 500 million people in sub-Saharan Africa. As technical partners to the Central and West African Virus Epidemiology (WAVE) programme, Gilligan’s group identified the location and timing of invasion into Zambia and the Democratic Republic of the Congo in 2018-19. WAVE has been implemented in ten countries (Benin, Burkina Faso, Cameroon, Côte d’Ivoire, DRC, Gabon, Ghana, Nigeria, Togo and Sierra Leone) with a combined population of 400 million.

“[Gilligan’s work has been] undoubtedly influential in focussing governments to develop an integrated programme for surveillance, preparedness and response to the disease. This has influenced policies in all ten countries and would not have been possible without the scientific work of the Cambridge team.”

– Executive Director, Central and West African Virus Epidemiology programme