The effect of polyploidization on tree hydraulic functioning
Autor: | Wannes Keulemans, Niels J. F. De Baerdemaeker, Kathy Steppe, Jan Van den Bulcke, Niek Hias |
---|---|
Rok vydání: | 2018 |
Předmět: |
0106 biological sciences
0301 basic medicine Malus Drought tolerance Plant Science 01 natural sciences Trees Polyploidy 03 medical and health sciences Parenchyma Genetics Water content Ecology Evolution Behavior and Systematics Water transport Dehydration biology fungi Water food and beverages biology.organism_classification Diploidy Wood Tetraploidy Horticulture 030104 developmental biology Shoot Desiccation Plant Shoots 010606 plant biology & botany Woody plant |
Zdroj: | American Journal of Botany. 105:161-171 |
ISSN: | 0002-9122 |
Popis: | PREMISE OF THE STUDY: Recent research has highlighted the importance of living tissue in wood. Polyploidization can impact amounts and arrangements of living cells in wood, potentially leading to increased drought tolerance. Tetraploid variants were created from the apple cultivar Malus xdomestica 'Gala' (Gala-4x), and their vulnerability to drought-induced cavitation and their hydraulic capacitance were compared to those of their diploid predecessors (Gala-2x). Assuming a positive correlation between polyploidy and drought tolerance, we hypothesized lower vulnerability and higher capacitance for the tetraploid. METHODS: Vulnerability to drought-induced cavitation and the hydraulic capacitance were quantified through acoustic emission and continuous weighing of shoots during a bench-top dehydration experiment. To underpin the hydraulic trait results, anatomical variables such as vessel area, conduit diameter, cell wall reinforcement, and ray and vessel-associated parenchyma were measured. KEY RESULTS: Vulnerability to drought-induced cavitation was intrinsically equal for both ploidy variants, but Gala-4x proved to be more vulnerable than Gala-2x during the early phase of desiccation as was indicated by its significantly lower air entry value. Higher change in water content of the leafy shoot, higher amount of parenchyma, and larger vessel area and size resulted in a significantly higher hydraulic capacitance and efficiency for Gala-4x compared to Gala-2x. CONCLUSIONS: Both ploidy variants were typified as highly sensitive to drought-induced cavitation, with no significant difference in their overall drought vulnerability. But, when water deficit is short and moderate, Gala-4x may delay a drought-induced decrease in performance by trading hydraulic safety for increased release of capacitively stored water from living tissue. |
Databáze: | OpenAIRE |
Externí odkaz: |