Xylem hydraulic characteristics, water relations and wood anatomy of the resurrection plant Myrothamnus flabellifoliusWelw
dc.contributor.author | Sherwin, Heather W | |
dc.contributor.author | Pammenter, N W | |
dc.contributor.author | February, E D | |
dc.contributor.author | Vander Willigen, Clare | |
dc.contributor.author | Farrant, Jill M | |
dc.date.accessioned | 2016-08-05T09:22:11Z | |
dc.date.available | 2016-08-05T09:22:11Z | |
dc.date.issued | 1998 | |
dc.date.updated | 2016-08-01T08:49:59Z | |
dc.description.abstract | Myrothamnus flabellifolius Welw. is a desiccation-tolerant (‘ resurrection’) plant with a woody stem. Xylem vessels are narrow (14 µm mean diameter) and perforation plates are reticulate. This leads to specific and leaf specific hydraulic conductivities that are amongst the lowest recorded for angiosperms (ks 0±87 kg m−" MPa−" s−"; kl 3±28¬10−& kg m−" MPa−" s−", stem diameter 3 mm). Hydraulic conductivities decrease with increasing pressure gradient. Transpiration rates in well watered plants were moderate to low, generating xylem water potentials of ®1 to ®2 MPa. Acoustic emissions indicated extensive cavitation events that were initiated at xylem water potentials of ®2 to ®3 MPa. The desiccation-tolerant nature of the tissue permits this species to survive this interruption of the water supply. On rewatering the roots pressures that were developed were low (2±4 kPa). However capillary forces were demonstrated to be adequate to account for the refilling of xylem vessels and re-establishment of hydraulic continuity even when water was under a tension of ®8 kPa. During dehydration and rehydration cycles stems showed considerable shrinking and swelling. Unusual knob-like structures of unknown chemical composition were observed on the outer surface of xylem vessels. These may be related to the ability of the stem to withstand the mechanical stresses associated with this shrinkage and swelling. | en_ZA |
dc.identifier | http://dx.doi.org/10.1006/anbo.1998.0590 | |
dc.identifier.apacitation | Sherwin, H. W., Pammenter, N. W., February, E. D., Vander Willigen, C., & Farrant, J. M. (1998). Xylem hydraulic characteristics, water relations and wood anatomy of the resurrection plant Myrothamnus flabellifoliusWelw. <i>Annals of Botany</i>, http://hdl.handle.net/11427/21129 | en_ZA |
dc.identifier.chicagocitation | Sherwin, Heather W, N W Pammenter, E D February, Clare Vander Willigen, and Jill M Farrant "Xylem hydraulic characteristics, water relations and wood anatomy of the resurrection plant Myrothamnus flabellifoliusWelw." <i>Annals of Botany</i> (1998) http://hdl.handle.net/11427/21129 | en_ZA |
dc.identifier.citation | SHERWIN, H. W., Pammenter, N. W., February, E. D., VANDER WILLIGEN, C. L. A. R. E., & FARRANT, J. M. (1998). Xylem Hydraulic Characteristics, Water Relations and Wood Anatomy of the Resurrection PlantMyrothamnus flabellifoliusWelw. Annals of Botany, 81(4), 567-575. | en_ZA |
dc.identifier.issn | 0305-7364 | en_ZA |
dc.identifier.ris | TY - Journal Article AU - Sherwin, Heather W AU - Pammenter, N W AU - February, E D AU - Vander Willigen, Clare AU - Farrant, Jill M AB - Myrothamnus flabellifolius Welw. is a desiccation-tolerant (‘ resurrection’) plant with a woody stem. Xylem vessels are narrow (14 µm mean diameter) and perforation plates are reticulate. This leads to specific and leaf specific hydraulic conductivities that are amongst the lowest recorded for angiosperms (ks 0±87 kg m−" MPa−" s−"; kl 3±28¬10−& kg m−" MPa−" s−", stem diameter 3 mm). Hydraulic conductivities decrease with increasing pressure gradient. Transpiration rates in well watered plants were moderate to low, generating xylem water potentials of ®1 to ®2 MPa. Acoustic emissions indicated extensive cavitation events that were initiated at xylem water potentials of ®2 to ®3 MPa. The desiccation-tolerant nature of the tissue permits this species to survive this interruption of the water supply. On rewatering the roots pressures that were developed were low (2±4 kPa). However capillary forces were demonstrated to be adequate to account for the refilling of xylem vessels and re-establishment of hydraulic continuity even when water was under a tension of ®8 kPa. During dehydration and rehydration cycles stems showed considerable shrinking and swelling. Unusual knob-like structures of unknown chemical composition were observed on the outer surface of xylem vessels. These may be related to the ability of the stem to withstand the mechanical stresses associated with this shrinkage and swelling. DA - 1998 DB - OpenUCT DP - University of Cape Town J1 - Annals of Botany LK - https://open.uct.ac.za PB - University of Cape Town PY - 1998 SM - 0305-7364 T1 - Xylem hydraulic characteristics, water relations and wood anatomy of the resurrection plant Myrothamnus flabellifoliusWelw TI - Xylem hydraulic characteristics, water relations and wood anatomy of the resurrection plant Myrothamnus flabellifoliusWelw UR - http://hdl.handle.net/11427/21129 ER - | en_ZA |
dc.identifier.uri | http://hdl.handle.net/11427/21129 | |
dc.identifier.vancouvercitation | Sherwin HW, Pammenter NW, February ED, Vander Willigen C, Farrant JM. Xylem hydraulic characteristics, water relations and wood anatomy of the resurrection plant Myrothamnus flabellifoliusWelw. Annals of Botany. 1998; http://hdl.handle.net/11427/21129. | en_ZA |
dc.language | eng | en_ZA |
dc.publisher | Oxford University Press | en_ZA |
dc.publisher.institution | University of Cape Town | |
dc.source | Annals of Botany | en_ZA |
dc.source.uri | http://aob.oxfordjournals.org/ | |
dc.subject.other | Cavitation | |
dc.subject.other | Desiccation | |
dc.subject.other | Hydraulic conductivity | |
dc.subject.other | Refilling | |
dc.subject.other | Resurrection plant | |
dc.title | Xylem hydraulic characteristics, water relations and wood anatomy of the resurrection plant Myrothamnus flabellifoliusWelw | en_ZA |
dc.type | Journal Article | en_ZA |
uct.type.filetype | Text | |
uct.type.filetype | Image | |
uct.type.publication | Research | en_ZA |
uct.type.resource | Article | en_ZA |