Silicon nutrition increases grain yield, which, in turn, exerts a feed-forward stimulation of photosynthetic rates via enhanced mesophyll conductance and alters primary metabolism in rice
Article first published online: 19 SEP 2012
© 2012 The Authors. New Phytologist © 2012 New Phytologist Trust
Volume 196, Issue 3, pages 752–762, November 2012
How to Cite
Detmann, K. C., Araújo, W. L., Martins, S. C. V., Sanglard, L. M. V. P., Reis, J. V., Detmann, E., Rodrigues, F. Á., Nunes-Nesi, A., Fernie, A. R. and DaMatta, F. M. (2012), Silicon nutrition increases grain yield, which, in turn, exerts a feed-forward stimulation of photosynthetic rates via enhanced mesophyll conductance and alters primary metabolism in rice. New Phytologist, 196: 752–762. doi: 10.1111/j.1469-8137.2012.04299.x
- Issue published online: 9 OCT 2012
- Article first published online: 19 SEP 2012
- Manuscript Accepted: 25 JUL 2012
- Manuscript Received: 23 JUN 2012
- Foundation for Research Assistance of the Minas Gerais State. Grant Number: APQ-02260-11
- National Council for Scientific and Technological Development. Grant Number: 302605/2010-0
- Brazilian Federal Agency
- mesophyll conductance;
- metabolic profiling;
- rice (Oryza sativa);
- silicon (Si);
- source–sink manipulation
- Silicon (Si) is not considered to be an essential element for higher plants and is believed to have no effect on primary metabolism in unstressed plants. In rice (Oryza sativa), Si nutrition improves grain production; however, no attempt has been made to elucidate the physiological mechanisms underlying such responses.
- Here, we assessed crop yield and combined advanced gas exchange analysis with carbon isotope labelling and metabolic profiling to measure the effects of Si nutrition on rice photosynthesis, together with the associated metabolic changes, by comparing wild-type rice with the low-Si rice mutant lsi1 under unstressed conditions.
- Si improved the harvest index, paralleling an increase in nitrogen use efficiency. Higher crop yields associated with Si nutrition exerted a feed-forward effect on photosynthesis which was fundamentally associated with increased mesophyll conductance. By contrast, Si nutrition did not affect photosynthetic gas exchange during the vegetative growth phase or in de-grained plants. In addition, Si nutrition altered primary metabolism by stimulating amino acid remobilization.
- Our results indicate a stimulation of the source capacity, coupled with increased sink demand, in Si-treated plants; therefore, we identify Si nutrition as an important target in attempts to improve the agronomic yield of rice.