Grass veins are leaky pipes : vessel widening in grass leaves explain variation in stomatal conductance and vessel diameter among species
© 2023 The Authors New Phytologist © 2023 New Phytologist Foundation.
| Veröffentlicht in: | The New phytologist. - 1979. - 241(2023), 1 vom: 14. Jan., Seite 243-252 |
|---|---|
| 1. Verfasser: | |
| Weitere Verfasser: | |
| Format: | Online-Aufsatz |
| Sprache: | English |
| Veröffentlicht: |
2024
|
| Zugriff auf das übergeordnete Werk: | The New phytologist |
| Schlagworte: | Journal Article biological scaling grass anatomy plant vasculature plant water use xylem taper Water 059QF0KO0R |
| Zusammenfassung: | © 2023 The Authors New Phytologist © 2023 New Phytologist Foundation. The widening of xylem vessels from tip to base of trees is an adaptation to minimize the hydraulic resistance of a long pathway. Given that parallel veins of monocot leaves do not branch hierarchically, vessels should also widen basipetally but, in addition to minimizing resistance, should also account for water volume lost to transpiration since they supply water to the lamina along their lengths, that is 'leakiness'. We measured photosynthesis, stomatal conductance, and vessel diameter at five locations along each leaf of five perennial grass species. We found that the rate of conduit widening in grass leaves was larger than the widening exponent required to minimize pathlength resistance (0.35 vs c. 0.22). Furthermore, variation in the widening exponent among species was positively correlated with maximal stomatal conductance (r2 = 0.20) and net CO2 assimilation (r2 = 0.45). These results suggest that faster rates of conduit widening (> 0.22) were associated with higher rates of water loss. Taken together, our results show that the widening exponent is linked to plant function in grass leaves and that natural selection has favored parallel vein networks that are constructed to meet transpiration requirements while minimizing hydraulic resistance within grass blades |
|---|---|
| Beschreibung: | Date Completed 11.12.2023 Date Revised 11.12.2023 published: Print-Electronic Citation Status MEDLINE |
| ISSN: | 1469-8137 |
| DOI: | 10.1111/nph.19368 |