Elevated carbon dioxide and nitrogen supply affect photosynthesis and nitrogen partitioning of two wheat varieties

Abstract

The response of wheat to elevated carbon dioxide concentration (e[CO₂]) is likely to be dependent on nitrogen supply. To investigate the underlying mechanism of growth response to e[CO₂], two wheat cultivars were grown under different carbon dioxide concentration [CO₂] in a chamber experimental facility. The changes in leaf photosynthesis, C and N concentration, and biomass were investigated under different [CO₂] and N supply. The result showed an increase in photosynthesis under e[CO₂] at all N level except the one with the lowest N supply. Furthermore, a significant decrease in g_s and Tr for both the cultivars was also observed under e[CO₂] at all N levels. A considerable increase in WUEi was observed for both the cultivars under e[CO₂] at all N levels except for the lowest concentration one. Therefore, the study shows that a stimulation of plant growth under e[CO₂] to be marginal at higher N supply.

Keywords:

• C and N concentrations
• elevated CO₂ concentration
• nitrogen
• photosynthesis
• wheat

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was partially supported by National Key R&D Program of China (2017YFD0300202-5), National Natural Science Foundation of China (31601212), Crop ecology and dry cultivation physiology key laboratory of Shanxi province (201705D111007), Research on Science and Technology of Shanxi Province (20150311006-2 and 201703D221033-1) and the Shanxi 100-Talent program.