Spatio-temporal response mechanism of physiological characteristics of Abies georgei var. smithii to altitude

Kang Chen,Zhiying Fan,Jiangrong Li,Kaiwen Pan,Weilie Zheng

doi:10.1051/e3sconf/202126901016

Abstract

Abies georgei var. smithii (Abies George I varsmithorr. II (Viguie et Gaussen) Cheng et l.) belongs to Abies of Pinaceae, which is distributed in the southeast of Tibet, southwest of Sichuan and northwest of Yunnan. In this study, Abies georgei var. smithii in Sejila Mountain of southeastern Tibet was studied, the contents of Malondialdehyde (MDA), proline (pro), hydrogen peroxide (H2O2), soluble sugar and chlorophyll as well as the activities of superoxide dismutase (SOD) and superoxide dismutase (SOD) in the leaves, twigs, tree stems and roots of Abies georgei var. smithii were measured at different altitudes in the growing and non-growing seasons, single factor analysis of variance and multiple comparison were used to process the data. The results showed that the contents of Malondialdehyde (MDA), proline (pro) and hydrogen peroxide (H2O2) in the roots of Abies georgei var. smithii were significantly higher than those of other tissues in both growing and non-growing seasons, the content of chlorophyll in the leaves increased at first and then decreased with the elevation gradient, on the contrary, the ratio of chlorophyll a/b (CHLA/CHLB) increased with the elevation gradient. The activities of Peroxidase (POD) and superoxide dismutase (SOD) were the lowest. When the altitude was more than 4300m, the activities of POD and SOD decreased. The results showed that the physiological resistance of Abies georgei var. smithii decreased when the elevation was over 3900m, which was not beneficial to the growth and development of Abies georgei var. smithii, therefore, the distribution of Abies georgei var. smithii along the higher elevation gradient was limited by the unfavorable environmental factors at high altitude.

Highlights

Linzhi, Tibet, as a small river in the south of Tibet, has high vegetation richness and obvious changes in altitude gradient
Use colorimetric method to determine the total chlorophyll, chlorophyll a, chlorophyll b content [4]; use the TBA colorimetric method to determine the MDA content [5]; determine the proline content using the ninhydrin colorimetric method [6]; starch and solubility The sugar content was determined by the anthrone sulfate method [7]; the hydrogen peroxide content was determined by the Jiancheng biological kit method [8]; the catalase POD and the superoxide dismutase SOD activity were measured by the Jiancheng biological kit method [9]
The above two items show that, in terms of parts, regardless of the growing season or the non-growing season, the firs at different altitudes suffer the least stress at the stem and the highest at the root

Summary

Introduction

Tibet, as a small river in the south of Tibet, has high vegetation richness and obvious changes in altitude gradient. With the increase in altitude, environmental factors such as temperature, humidity, sunlight radiation, and atmospheric pressure have all undergone drastic changes, which have become a hot spot in the academia to study plant changes in the environment. In high-altitude areas, the growth and development of vegetation is restricted by multiple factors such as moisture, light, temperature, etc. There is little knowledge about how the altitude gradient affects the intrinsic physiological characteristics of vegetation. The alpine area of Sejila Mountain has distinct topography and landforms and complex and diverse climate, especially the vertical climate change is obvious. It is an ideal place to study the adaptation of vegetation to external environmental changes and molecular evolution [1].

Methods

Results

Discussion

Conclusion