Effects of elevated CO2 on processing quality characteristics of two winter wheat genotypes under CGC experiment system

Elevated CO2 concentration during coming decades would impact crop quality. Thus, the objective of this study was to determine whether CO2 enrichment levels would modify some aspects of grain quality relevant to processing, including flour protein, dough properties and baking properties. Wheat of two genotypes (ZhongYu five, middle-protein content of wheat genotype; and Zhongyou 9701, high-protein content of wheat genotype) was grown in CO2 Gradient Chamber (CGC) and Ambient controlled chamber, respectively. The results indicated that protein content for flour was found to significant decrease with CO2 concentration increasing. In that case of CO2 level increasing gradually from 451 to 565 mu mol mol(-1), the flour protein contents on ZhongYu five and Zhongyou 9701 reduced 4.5% & 3.1%, respectively. Elevated CO2 affected adversely on rheology characteristics of dough such as farinograph development time and dough extensibility; however, there were minor changes on farinograph parameters in Zhongyou 9701 under CO2 enrichment condition. Moreover, elevated CO2 affected severely baking properties and especially decreased bread loaf volumes of two wheat genotypes.