A pan-European analysis of the spatio-temporal patterns of yield gap and abiotic stresses for wheat

Abstract

Environment characterization and yield gap analysis are important for plant breeding to understand genotype by environment interactions and to optimize field trial networks. This understanding is a key aspect to reach the needed improvements in crop yield to achieve food security and for agricultural and environment policy evaluations. However, a characterization of abiotic stress scenarios of their recent changes at the European level for rainfed wheat are still missing. Here, wheat responses to various combinations of environmental stresses (that is, water, nitrogen and temperature limitations) were simulated at a spatial resolution of 25 × 25 km for the period 1985-2014. Results showed that at the European level, environmental stresses have resulted in an average production loss of 111.4 million tons per annum, of which 59% was contributed to by drought. Over the studied period, simulated environmental yield gap decreased at a rate of 0.22% per annum, in particular water-limited yield gap has decreased at lower latitudes but it has increased in continental regions. Five environment types were identified based on daily patterns of total above ground biomass loss due to water deficit. The spatio-temporal patterns of the identified environment types show that the occurrence probability of environments without drought or with mild water shortage has been increasing at the European level while that of mild water stress from the vegetative stage onwards and severe water shortage between anthesis and maturity has been decreasing. Among the nine largest wheat producing European countries, these changes were particularly significant in Italy, Romania and Spain