Polyploidy enhances the occupation of heterogeneous environments through hydraulic related trade-offs in Atriplex canescens (Chenopodiaceae)
Article first published online: 3 DEC 2012
No claim to original US government works. New Phytologist © 2012 New Phytologist Trust
Volume 197, Issue 3, pages 970–978, February 2013
How to Cite
Hao, G.-Y., Lucero, M. E., Sanderson, S. C., Zacharias, E. H. and Holbrook, N. M. (2013), Polyploidy enhances the occupation of heterogeneous environments through hydraulic related trade-offs in Atriplex canescens (Chenopodiaceae). New Phytologist, 197: 970–978. doi: 10.1111/nph.12051
- Issue published online: 7 JAN 2013
- Article first published online: 3 DEC 2012
- Manuscript Accepted: 14 OCT 2012
- Manuscript Received: 21 AUG 2012
- Ministry for Environment, Land and Sea
- drought tolerance;
- flow cytometry;
- niche differentiation;
- plant hydraulics;
- water relations
- Plant hydraulic characteristics were studied in diploid, tetraploid and hexaploid cytotypes of Atriplex canescens (Chenopodiaceae) to investigate the potential physiological basis underlying the intraspecific habitat differentiation among plants of different ploidy levels.
- Populations of A. canescens from different habitats of the Chihuahuan Desert (New Mexico, USA) were analyzed using flow cytometry to determine ploidy levels. Traits related to xylem water transport efficiency and safety against drought-induced hydraulic failure were measured in both stems and leaves.
- At the stem level, cytotypes of higher ploidy showed consistently lower leaf-specific hydraulic conductivity but greater resistance to drought-induced loss of hydraulic conductivity. At the leaf level, comparisons in hydraulics between cytotypes did not show a consistent pattern, but exhibited high plasticity to proximal environmental conditions related to soil water availability.
- The results suggest that a trade-off between stem hydraulic efficiency and safety across ploidy levels underlies niche differentiation among different cytotypes of A. canescens. Polyploidization may have been facilitated by environmental heterogeneity related to water availability, and variation in water-related physiology found in the present study suggests an important functional basis for the niche differentiation and coexistence of A. canescens cytotypes in desert environments.