Enhanced growth rate under elevated CO2 conditions was observed for transgenic lines of genes identified by intraspecific variation analyses in Arabidopsis thaliana.

ABSTRACT

KEY MESSAGE Using the whole genome and growth data of Arabidopsis thaliana ecotypes, we identified two genes associated with enhancement of the growth rate in response to elevated CO2 conditions. Improving plant growth under elevated CO2 conditions may contribute to enhanced agricultural yield under future global climate change. In this study, we examined the genes implicated in the enhancement of growth rates under elevated CO2 conditions by analyzing the growth rates of Arabidopsis thaliana ecotypes originating from various latitudes and altitudes throughout the world. We also performed a genome-wide association study and a transcriptome study to identify single nucleic polymorphisms that were correlated with the relative growth rate (RGR) under elevated CO2 conditions or with CO2 response of RGR. We then selected 43 candidate genes and generated their overexpression and/or RNA interference (RNAi) transgenic mutants for screening. After screening, we have found that RNAi lines of AT3G4000 and AT5G50900 showed significantly higher growth rates under the elevated CO2 condition. As per our findings, we conclude that natural variation includes genetic variation associated with the enhancement of plant productivity under elevated CO2 conditions.