在水分充足和干旱条件下，蓝桉无性系的木质部空穴化、叶片生长和叶片水势

Xylem cavitation, leaf growth and leaf water potential in Eucalyptus globulus clones under well-watered and drought conditions.

作者信息

Pita Pilar, Gascó Antonio, Pardos José A

机构信息

Unidad de Anatomía, Fisiología y Genética Forestal, Escuela Técnica Superior de Ingenieros de Montes, Ciudad Universitaria s/n, 28040 Madrid, Spain. Corresponding author; email:

Unidad de Anatomía, Fisiología y Genética Forestal, Escuela Técnica Superior de Ingenieros de Montes, Ciudad Universitaria s/n, 28040 Madrid, Spain.

出版信息

Funct Plant Biol. 2003 Sep;30(8):891-899. doi: 10.1071/FP03055.

DOI:10.1071/FP03055

PMID:32689073

Abstract

Leaf growth, predawn leaf water potential (Ψ), evapotranspiration, stem maximum permeability, and its percentage loss of hydraulic conductivity (PLC) were measured in rooted cuttings of selected clones of Eucalyptus globulus Labill. subjected to well-watered and drought conditions. Drought significantly reduced evapotranspiration, leaf growth and maximum permeability. E. globulus clones lost up to 70% of conductivity at values of Ψ less negative than -1 MPa. PLC values higher than 85% could not be measured without causing leaf shedding. The coefficient related to the slope of the vulnerability curves ranged from 1.52-2.23. The lowest value was measured in the most drought-resistant clone, as estimated from field trials. Plants from this clone displayed higher drought-induced reductions in maximum permeability than plants from other clones, had significantly smaller leaves and maintained higher values of predawn leaf water potential as soil water content (SWC) declined.

摘要

在充分浇水和干旱条件下，对蓝桉（Eucalyptus globulus Labill.）选定无性系的生根插条进行了叶片生长、黎明前叶片水势（Ψ）、蒸散量、茎最大导水率及其水力传导率损失百分比（PLC）的测定。干旱显著降低了蒸散量、叶片生长和最大导水率。当Ψ值低于-1 MPa且负值较小时，蓝桉无性系的导水率损失高达70%。在不引起叶片脱落的情况下，无法测量PLC值高于85%的情况。与脆弱性曲线斜率相关的系数范围为1.52 - 2.23。从田间试验估计，在最抗旱的无性系中测得的该值最低。与其他无性系的植株相比，该无性系的植株在干旱诱导下最大导水率的降低幅度更大，叶片明显更小，并且随着土壤含水量（SWC）的下降，黎明前叶片水势保持较高值。