Significant decrease in yield under future climate conditions: Stability and production of 138 spring barley accessions

The response in production parameters to projected future levels of temperature, atmospheric carbon dioxide ([CO2]), and ozone ([O-3]) was investigated in 138 spring barley accessions. The comprehensive set of landraces, cultivars, and breeder-lines, were during their entire life cycle exposed to a two-factor treatment of combined elevated temperature (+5 degrees C day/night) and [CO2] (700 ppm), as well as single-factor treatments of elevated temperature (+5 degrees C day/night), [CO2] (700 ppm), and [O-3] (100-150 ppb). The control treatment was equivalent to present average South Scandinavian climate (temperature: 19/12 degrees C (day/night), [CO2]: 385 ppm). Overall grain yield was found to decrease 29% in the two-factor treatment with concurrent elevation of [CO2] and temperature, and this response could not be predicted from the results of treatments with elevated [CO2] and temperature as single factors, where grain yield increased 16% and decreased 56%, respectively. Elevated [O-3] was found to decrease grain yield by 15%. Substantial variation in response to the applied climate treatments was found between the accessions. The results revealed landraces, cultivars, and breeder-lines with phenotypes applicable for breeding towards stable and high yield under future climate conditions. Further, we suggest identifying resources for breeding under multifactor climate conditions, as single-factor treatmentAid not accurately forecast the response, when factors were combined. (C) 2014 Elsevier B.V. All rights reserved.