Variable tolerance of wetland tree species to combined salinity and waterlogging is related to regulation of ion uptake and production of organic solutes
Article first published online: 26 AUG 2005
Volume 169, Issue 1, pages 123–134, January 2006
How to Cite
Carter, J. L., Colmer, T. D. and Veneklaas, E. J. (2006), Variable tolerance of wetland tree species to combined salinity and waterlogging is related to regulation of ion uptake and production of organic solutes. New Phytologist, 169: 123–134. doi: 10.1111/j.1469-8137.2005.01552.x
- Issue published online: 26 AUG 2005
- Article first published online: 26 AUG 2005
- Received: 18 May 2005 Accepted: 16 July 2005
- folial Na+ and Cl− concentrations;
- leaf sap osmotic potential;
- methyl proline;
- woody species
- • Melaleuca cuticularis and Casuarina obesa occur in wetlands, whereas Banksia attenuata occurs in adjacent well-drained sandy soils. Salt and waterlogging tolerances in these tree species were studied, as the levels of these stresses have increased in south-western Australia.
- • Seedlings were exposed to 0.01, 200 or 400 mm NaCl, with or without waterlogging, in a sand culture with nutrient solution for 22 d in a glasshouse.
- • Melaleuca cuticularis and C. obesa survived all treatments, and generally maintained high rates of net photosynthesis. Banksia attenuata tolerated neither waterlogging nor salinity. Salt tolerance of M. cuticularis and C. obesa was associated with the regulation of foliar sodium (Na+), chloride (Cl−) and potassium (K+) concentrations. Under saline-waterlogged conditions, this regulation was maintained in M. cuticularis, but was reduced in C. obesa. Foliage of these two species also contained appreciable levels of compatible organic solutes: methyl proline in M. cuticularis and proline in C. obesa; in both cases the concentrations increased at higher salinity.
- • Melaleuca cuticularis formed a higher proportion of aerenchyma in adventitious roots than C. obesa, so enhanced internal root aeration in M. cuticularis might contribute to its higher tolerance of combined salinity and waterlogging.