Article,
Effects of free-air CO2 enrichment and nitrogen supply on grain quality parameters and elemental composition of wheat and barley grown in a crop rotation
Agriculture, Ecosystems & Environment, 136 (1-2): 59--68 (Feb 15, 2010)
DOI: 10.1016/j.agee.2009.11.009
Abstract
With respect to European growth conditions very little information is available on how future atmospheric CO 2 concentrations CO 2 might affect quality characteristics of important crops. Winter wheat cv. 'Batis' and winter barley cv. 'Theresa' were grown for two growing seasons each under ambient CO 2 (ca. 375 μmol mol −1 ) and elevated CO 2 (550 μmol mol −1 ) with two different nitrogen (N) fertilization levels (adequate N supply / ca. 50\% of adequate N) in the course of a six year crop rotation. Effects on grain quality and grain elemental composition were investigated. Grain crude protein concentrations were lowered under elevated CO 2 by −4\% to −13\% in wheat and by −11\% to −13\% in barley. Reduced N supply decreased crude protein concentrations in wheat and barley by −14\% to −22\% and by −12\% to −19\%, respectively. In both species, starch concentration was increased by +4\% on average due to reduced N fertilization. In wheat, both CO 2 enrichment and low N supply reduced the activity of total and soluble β-amylase (−11\% and −7\%), Hagberg falling number (−7\%), and single kernel hardness (−18\%). In barley, both of the treatments induced reductions in the viscosity of the water extract (−25\% on average). Concerning minerals, sulphur concentrations were depleted under both elevated CO 2 and low N supply by averages of −5\% in wheat and −14\% in barley. Reduced N supply caused −8\% lower means of wheat grain calcium concentrations and reduced zinc concentrations on average by −23\%. According to these results, flour from cereal grains grown under elevated CO 2 and/or low N fertilization will have a diminished nutritional and processing quality and an altered elemental composition.
