Pathogens and pests that attack crops are a real burden for plant health and global food production. They take a heavy economic toll and put a strain on food security. Although many different players in food crop production report losses, it is very difficult to quantify yield losses and make comparisons between different crops, agroecosystems and regions. INRA researchers and their foreign counterparts recently published estimates of yield losses for five key global crops in Nature Ecology & Evolution.
A global study on crop pathogens and pests
In order to get hard and fast figures for the losses incurred by pathogens and pests in food crop production, an international team of researchers carried out a vast study on a global scale. The study, which took place between 1 November 2016 and 31 January 2017, benefited from the support of the International Society for Plant Pathology (ISPP) and a slew of institutions around the world. A questionnaire was distributed to more than 2,500 members of ISPP and many other players. The researchers were therefore able to collect and analyse close to 1,000 responses from 219 plant health experts on five major crops (wheat, rice, maize, soy and potato) in 67 countries. These 67 countries account for a large portion (87%) of the global production of these crops.
Losses of more than 40% for some crops
The study reported on losses associated with 137 pathogens and pests worldwide. Overall, estimates of losses mount to 10.1-28.1% for wheat; 24.6-40.9% for rice; 19.5-41.1% for maize; 8.1-21.0% for potato; and 11.0-32.4% for soy. The study also provided estimates for 137 pests that plague crops around the world and in major food crop production and consumption regions: Northwest Europe; Mid-West US and southern Canada; South Brazil and North Argentina; Indo-Gangetic Plains in South Asia; plains of China; Southeast Asia; and Sub-Saharan Africa. The results allowed scientists to measure the impact of plant health on global food security, and provided crucial data on the impact of emerging pathogens and pests. The findings may be used to define or reinforce research priorities when it comes to managing crop health, and ultimately improving the sustainability of agroecosystems.