High temperatures over several days or more for a crop such as corn (maize) can reduce the crop yield substantially. But new crop research reveals that it is not so much the heat and heat stress that impacts the plants, but water stress caused by increased evapo-transpiration through vapour pressure deficit (VPD) - the plants version of human sweating to cool down.
The new understanding comes from research and modelling by one of Australia's leading crop scientists, Professor Graeme Hammer, from the University of Queensland. Graeme has spent much of the last decade as professor in crop science at UQ's Queensland Alliance for Agriculture and Food Innovation (QAAFI) developing increasingly sophisticated computer models to predict the growth and yield of agricultural crops. Lead author for the study was David Lobell, an Assistant Professor in Environmental Earth System Science and Associate Director of the Center on Food Security and the Environment at Stanford University.
