Feeding the world in a variable climate: unravelling the plasticity of crop plants

Over the past century, genetic improvement of crops, combined with modern agronomic practices, has underpinned massive increases in yield and food production. This enabled continued exponential growth of the global human population and increased per capita wealth, resulting in a higher proportion of calorific intake from energy-inefficient heterotrophic livestock. However, most of these gains from the ‘Green Revolution’ were achieved in a period of relative climate stability, compared with the ongoing period of increased climate change and variability. Crop breeding has increasingly become an interdisciplinary exercise in managing complexity. The success of modern plant breeding programs has been based on careful selection, inbreeding, and hybridisation, informed by a framework of Mendelian and quantitative genetics. Recent advances making use of whole genome sequence and marker systems are increasingly based on understanding the ensemble contribution of the genome combined with reductionist approaches to increase the predictability of breeding designs and decisions. However, despite these advances in precision genetics for selection of parents and offspring, yield increases have now slowed.