Enhanced Stomatal Conductance by a Spontaneous Arabidopsis Tetraploid, Me-0, Results from Increased Stomatal Size and Greater Stomatal Aperture
by Monda K., Araki H., Kuhara S., Ishigaki G., Akashi R., Negi J., Kojima M., Sakakibara H., Takahashi S., Hashimoto-Sugimoto M., Goto N., Iba K. (2016)
- Keina Monda,
- Hiromitsu Araki2,
- Satoru Kuhara,
- Genki Ishigaki,
- Ryo Akashi,
- Juntaro Negi,
- Mikiko Kojima,
- Hitoshi Sakakibara,
- Sho Takahashi,
- Mimi Hashimoto-Sugimoto3,
- Nobuharu Goto and
- Koh Iba*
Department of Biology, Faculty of Science, Kyushu University, Fukuoka 819–0395, Japan (K.M., J.N., S.T., M.H.-S., K.I.);
Department of Bioscience and Biotechnology, Faculty of Agriculture, Kyushu University, Fukuoka 812–8581, Japan (H.A., S.K);
Department of Animal and Grassland Sciences, Faculty of Agriculture, University of Miyazaki, Miyazaki 889–2192, Japan (G.I., R.A.);
RIKEN Center for Sustainable Resource Science, Yokohama, Kanagawa 230–0045, Japan (M.K., H.S.); and
RIKEN BioResource Center, Koyadai, Tsukuba, Ibaraki 305–0074, Japan (N.G.)
in Plant Physiology March 2016 vol. 170 no. 3 1435-1444 – doi: http://dx.doi.org/10.1104/pp.15.01450
The rate of gas exchange in plants is regulated mainly by stomatal size and density. Generally, higher densities of smaller stomata are advantageous for gas exchange; however, it is unclear what the effect of an extraordinary change in stomatal size might have on a plant’s gas-exchange capacity.
We investigated the stomatal responses to CO2concentration changes among 374 Arabidopsis (Arabidopsis thaliana) ecotypes and discovered that Mechtshausen (Me-0), a natural tetraploid ecotype, has significantly larger stomata and can achieve a high stomatal conductance.
We surmised that the cause of the increased stomatal conductance is tetraploidization; however, the stomatal conductance of another tetraploid accession, tetraploid Columbia (Col), was not as high as that in Me-0. One difference between these two accessions was the size of their stomatal apertures.
Our results show that Me-0 overcomes the handicap of stomatal opening that is typical for tetraploids and achieves higher stomatal conductance compared with the closely related tetraploid Col on account of larger stomatal apertures.
This study provides evidence for whether larger stomatal size in tetraploids of higher plants can improve stomatal conductance.