30 种亚热带木本植物的叶片生物力学阻力与水力安全之间的协调关系。

Co-ordination between leaf biomechanical resistance and hydraulic safety across 30 sub-tropical woody species.

机构信息

State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, Guangxi Key Laboratory of Forest Ecology and Conservation, Guangxi University, Nanning, Guangxi, China.

Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, Guangdong, China.

出版信息

Ann Bot. 2021 Jul 30;128(2):183-191. doi: 10.1093/aob/mcab055.

DOI:10.1093/aob/mcab055

PMID:33930116

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC8324032/

Abstract

BACKGROUND AND AIMS

Leaf biomechanical resistance protects leaves from biotic and abiotic damage. Previous studies have revealed that enhancing leaf biomechanical resistance is costly for plant species and leads to an increase in leaf drought tolerance. We thus predicted that there is a functional correlation between leaf hydraulic safety and biomechanical characteristics.

METHODS

We measured leaf morphological and anatomical traits, pressure-volume parameters, maximum leaf hydraulic conductance (Kleaf-max), leaf water potential at 50 % loss of hydraulic conductance (P50leaf), leaf hydraulic safety margin (SMleaf), and leaf force to tear (Ft) and punch (Fp) of 30 co-occurring woody species in a sub-tropical evergreen broadleaved forest. Linear regression analysis was performed to examine the relationships between biomechanical resistance and other leaf hydraulic traits.

KEY RESULTS

We found that higher Ft and Fp values were significantly associated with a lower (more negative) P50leaf and a larger SMleaf, thereby confirming the correlation between leaf biomechanical resistance and hydraulic safety. However, leaf biomechanical resistance showed no correlation with Kleaf-max, although it was significantly and negatively correlated with leaf outside-xylem hydraulic conductance. In addition, we also found that there was a significant correlation between biomechanical resistance and the modulus of elasticity by excluding an outlier.

CONCLUSIONS

The findings of this study reveal leaf biomechanical-hydraulic safety correlation in sub-tropical woody species.

摘要

背景与目的

叶片的生物力学阻力可以保护叶片免受生物和非生物因素的破坏。先前的研究表明，增强叶片的生物力学阻力会对植物物种造成代价，并导致叶片耐旱性的提高。因此，我们预测叶片水力安全和生物力学特征之间存在功能相关性。

方法

我们测量了 30 种亚热带常绿阔叶林中木本植物的叶片形态和解剖特征、压力-容积参数、最大叶片水力导度（Kleaf-max）、水力导度损失 50%时的叶片水势（P50leaf）、叶片水力安全余量（SMleaf）以及叶片撕裂力（Ft）和冲孔力（Fp）。采用线性回归分析来检验生物力学阻力与其他叶片水力特性之间的关系。

主要结果

我们发现，较高的 Ft 和 Fp 值与较低的（更负的）P50leaf 和较大的 SMleaf 显著相关，从而证实了叶片生物力学阻力与水力安全之间的相关性。然而，尽管与叶片外木质部水力导度显著负相关，但叶片生物力学阻力与 Kleaf-max 之间并无相关性。此外，通过排除一个异常值，我们还发现生物力学阻力与弹性模量之间存在显著相关性。