Nitrogen-limited growth of lettuce is associated with lower stomatal conductance
Article first published online: 21 DEC 2001
Volume 152, Issue 1, pages 97–106, October 2001
How to Cite
Broadley, M. R., Escobar-Gutiérrez, A. J., Burns, A. and Burns, I. G. (2001), Nitrogen-limited growth of lettuce is associated with lower stomatal conductance. New Phytologist, 152: 97–106. doi: 10.1046/j.0028-646x.2001.00240.x
- Issue published online: 21 DEC 2001
- Article first published online: 21 DEC 2001
- Received: 9 April 2001Accepted: 26 June 2001
- Lactuca sativa (lettuce);
- relative growth rate (RGR);
- stomatal index;
- stomatal conductance;
- nitrogen deficiency
- • C assimilation (A) has been shown to limit the growth of young Lactuca sativa (lettuce) plants following an interruption in their external N supply. Further data from these plants were used to test two hypotheses: that N-limited growth of lettuce is associated with lower stomatal conductance (gs); and that reductions in gs result from adjustments to stomatal frequency or distribution.
- • The photosynthetic characteristics, nitrate and organic N-concentrations, as well as epidermal and stomatal distributions, were determined in leaves of hydroponically grown lettuce plants supplied continuously with N or with N removed for up to 14 d.
- • Although N-limited plants had lower maximum rates of A, comparisons at equivalent values of gs showed that A was not directly limited by organic-N but by gs. Reductions in gs under N-limiting conditions did not associate with adjustments to stomatal frequency or distribution.
- • Associations between plant N and A could arise either through stomata responding directly to signals induced by N deprivation or to increased CO2 partial pressure at the sites of carboxylation.