2009). All of these include experiments comparing contrasting cultivars carrying candidate traits for better performance under
e[CO2], at present mainly such traits that have been identified as potentially governing the extent of growth and yield responses (e.g. traits regarding sink strength, such as tillering capacity). However, it will also be important to evaluate under e[CO2] the selection of traits that are targeted for other reasons, e.g. nutrient and water use efficiency traits, stress tolerance traits or quality traits.