Vol.:(0123456789) 1 3 Journal of Plant Research https://doi.org/10.1007/s10265-018-1058-1 REGULAR PAPER Dependence of functional traits related to growth rates and their CO 2 response on multiple habitat climate factors across Arabidopsis thaliana populations Hiroshi Ozaki 1,2  · Riichi Oguchi 1  · Kouki Hikosaka 1 Received: 11 May 2017 / Accepted: 6 July 2018 © The Botanical Society of Japan and Springer Japan KK, part of Springer Nature 2018 Abstract The values of many plant traits are often diferent even within a species as a result of local adaptation. Here, we studied how multiple climate variables infuence trait values in Arabidopsis thaliana grown under common conditions. We examined 9 climate variables and 29 traits related to vegetative growth rate in 44 global A. thaliana accessions grown at ambient or elevated CO 2 concentration ([CO 2 ]) and applied a multiple regression analysis. We found that genetic variations in the traits related to growth rates were associated with various climate variables. At ambient [CO 2 ], plant size was positively correlated with precipitation in the original habitat. This may be a result of larger biomass investment in roots at the initial stage in plants adapting to a lower precipitation. Stomatal conductance and photosynthetic nitrogen use efciency were negatively correlated with vapor pressure defcit, probably as a result of the trade-of between photosynthetic water- and nitrogen-use efciency. These results suggest that precipitation and air humidity infuence belowground and aboveground traits, respec- tively. Elevated [CO 2 ] altered climate dependences in some of the studied traits. The CO 2 response of relative growth rate was negatively correlated with altitude, indicating that plants inhabiting a higher altitude have less plasticity to changing [CO 2 ]. These results are useful not only for understanding evolutionary process but also to predict the plant species that are favored under future global change. Keywords Ecotype · Functional traits · Global change · Growth analysis · Habitat fltering · Local adaptation Introduction There are quantitative variations in many plant traits among and within species. Part of the variations may be explained by local adaptation; trait values that maximize ftness difer depending on environmental conditions, and the selected species or genotypes difer among habitats (Cornwell and Ackerly 2009). If a plant could alter its trait optimally, it would be able to dominate in every habitat, but the potential distribution of a species or a genotype is limited, probably because of a limitation in phenotypic plasticity. The relative growth rate (RGR) is one of the most impor- tant components of ftness in plants and is an integration of various physiological and morphological plant traits. A higher RGR may be achieved if the leaves have a higher leaf photosynthetic capacity, if more biomass is allocated to leaves and/or if the leaf mass per area (LMA) is low to receive more light (Poorter et al. 2009). A higher photosyn- thetic capacity may be achieved if the leaves accumulate more nitrogen or have a higher photosynthetic nitrogen-use efciency (photosynthesis per leaf nitrogen). A greater accu- mulation of leaf nitrogen may be a result of a higher nitrogen absorption rate or a larger allocation of plant nitrogen to leaves. These relationships among functional traits are for- mulated in growth analysis models (Garnier 1991; Hikosaka and Osone 2009; Hunt 1978; Lambers and Poorter 1992). Recent feld studies have revealed that values of some functional traits related to RGR are strongly related to the Electronic supplementary material The online version of this article (https://doi.org/10.1007/s10265-018-1058-1) contains supplementary material, which is available to authorized users. * Hiroshi Ozaki ozakihiroshi0217@gmail.com 1 Graduate School of Life Sciences, Tohoku University, Sendai, Miyagi 980-8578, Japan 2 Present Address: School of Life Sciences, Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji, Tokyo 192-0392, Japan