Food system consequences of a fungal disease epidemic in a major crop

Journal article

Fungal diseases are major threats to the most important crops upon which humanity depends. Were there to be a major epidemic that severely reduced yields its effects would spread throughout the globalised food system. To explore these ramifications we use a partial equilibrium economic model of the global food system (IMPACT) to study a hypothetical severe but short-lived epidemic that reduces rice yields in the countries affected by 80%. We modelled a succession of epidemic scenarios of increasing severity, starting with the disease in a single country in south-east Asia and ending with the pathogen present in most of eastern Asia. The epidemic and subsequent crop losses led to substantially increased global rice prices. However, as long as global commodity trade was unrestricted and able to respond fast enough, the effects on individual calorie consumption were to a large part mitigated. Some of the worse effects were projected to be experienced by poor net-rice importing countries in sub-Saharan Africa, which were not affected directly by the disease but suffered because of higher rice prices. We critique the assumptions of our models, and explore political economic pressures to restrict trade at times of crisis. We finish by arguing for the importance of “stress-testing” the resilience of the global food system to crop disease and other shocks.

Authors: Godfray, H; Mason-D'Croz, D; Robinson, S

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: Royal Society
• Journal: Philosophical Transactions of the Royal Society B: Biological Sciences
• Volume: 371
• Issue: 1709
• Pages: 20150467
• Publication date: 2016-12-01
• Acceptance date: 2016-06-14
• DOI: 10.1098/rstb.2015.0467
• EISSN: 1471-2970
• ISSN: 0962-8436
• Keywords: rice; trade; Fungal pathogen; prices; partial-equilibrium economic model