Chin J Plant Ecol ›› 2022, Vol. 46 ›› Issue (2): 136-147.

• Research Articles •

Relationships between lamina size, vein density and vein cell wall dry mass per unit vein length of broad-leaved woody species in Tiantong Mountain, southeastern China

XIONG Ying-Jie*, YU Guo*, WEI Kai-Lu, PENG Juan, GENG Hong-Ru, YANG Dong-Mei, PENG Guo-Quan**()

1. College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua, Zhejiang 321004, China
• Received:2021-02-22 Accepted:2021-09-27 Online:2022-02-20 Published:2022-01-07
• Contact: PENG Guo-Quan
• About author:Contributed equally to this work
• Supported by:
National Natural Science Foundation of China(31770647);Ten Thousand Talents Program of Zhejiang Province(2019R52014)

Abstract:

Aims Leaf size is a key determinant of plant ecological strategy, and leaf vein is the main support and transport structure in leaf, which has an important role in the growth and development of leaf. The purpose of this study was to explore the evolutionary mechanism of leaf size by analyzing the relationships among lamina size, vein density as well as vein cell wall construction cost.

Methods In this study, 38 broad-leaved woody species were selected from Tiantong Mountain, southeastern China. The leaf size was characterized by lamina area, lamina dry mass and lamina perimeter. The standardized major axis estimation (SMA) and phylogenetically independent contrasts (PIC) methods were used to analyze the relationships between lamina size and major vein density, minor vein density, total vein density, as well as the cell wall construction cost per unit length of each order vein.

Important findings Our results demonstrated that: (1) Lamina size was significantly and negatively correlated with major vein density, but not with minor vein density and total vein density, indicating that the small leaves are generally with higher major vein density than those of large leaves, by contrast, the density of minor veins were independent of the final leaf size as was the total vein density; (2) There was a significantly positive correlation between lamina size and the cell wall mass per unit length of major vein, while there were no significant correlations between lamina size and the cell wall mass per unit length of minor vein and total vein, indicating that the biomass investment in cell wall per unit length of major veins would increase significantly with the increase of lamina size, while the biomass investment in cell wall per unit length of minor vein was independent of lamina size; (3) There was an allometric relationship with the slope significantly greater than -1 between the major vein density and their cell wall mass per unit length, and there was no significant correlation between the minor vein density and their cell wall mass per unit length, indicating that the major vein density would decrease significantly with the increase of the construction cost of the major vein. This is a trade-off allometric relationship, while the minor vein density was not affected by their construction cost. These results indicated that the high density of major veins in small leaves is not only the result of leaf shape regulation during leaf development, but also the result of a cost-benefit trade-off of vein cell wall construction. The results of this study have unique and key implications for understanding the global plant biogeographical trends of leaf size and the adaptation strategies of plants to the environment.