title: Soil warming enhances the hidden shift of elemental stoichiometry by elevated CO2 in wheat.
abstract: Increase in atmospheric CO2 concentration ([CO2]) and associated soil warming along with global climate change are expected to have large impacts on grain mineral nutrition in wheat. The effects of CO2 elevation (700 μmol l(-1)) and soil warming (+2.4 °C) on K, Ca and Mg concentrations in the xylem sap and their partitioning in different organs of wheat plant during grain filling were investigated. Results showed that the combination of elevated [CO2] and soil warming improved wheat grain yield, but decreased plant K, Ca and Mg accumulation and their concentrations in the leaves, stems, roots and grains. The reduced grain mineral concentration was attributed to the lowered mineral uptake as exemplified by both the decreased stomatal conductance and mineral concentration in the xylem sap. These findings suggest that future higher atmospheric [CO2] and warmer soil conditions may decrease the dietary availability of minerals from wheat crops. Breeding wheat cultivars possessing higher ability of mineral uptake at reduced xylem flux in exposure to climate change should be a target.
authors.affiliation: University of Copenhagen, Faculty of Science, Department of Plant and Environmental Sciences, Højbakkegaard Allé 13, 2630 Tåstrup, Denmark.
authors.forename: Xiangnan
authors.initials: X
authors.lastname: Li
authors.affiliation: National Engineering and Technology Center for Information Agriculture/Key Laboratory of Crop Physiology and Ecology in Southern China, Ministry of Agriculture, Nanjing Agricultural University, Nanjing, China.
authors.forename: Dong
authors.initials: D
authors.lastname: Jiang
authors.affiliation: University of Copenhagen, Faculty of Science, Department of Plant and Environmental Sciences, Højbakkegaard Allé 13, 2630 Tåstrup, Denmark.
authors.forename: Fulai
authors.initials: F
authors.lastname: Liu
mesh_terms: D002245:Carbon Dioxide / Q000032:analysis*; D012987:Soil; D013696:Temperature; D014908:Triticum / Q000737:chemistry*
chemical_list: D012987:Soil; D002245:Carbon Dioxide