干旱区研究 ›› 2024, Vol. 41 ›› Issue (1): 92-103.doi: 10.13866/j.azr.2024.01.09

• 植物生态 • 上一篇    下一篇

珍珠柴幼苗叶片和根系形态特征对干旱胁迫的响应

颜巧芳(),单立山(),解婷婷,王红永,师亚婷   

  1. 甘肃农业大学林学院,甘肃 兰州 730070
  • 收稿日期:2023-05-15 修回日期:2023-08-24 出版日期:2024-01-15 发布日期:2024-01-24
  • 通讯作者: 单立山. E-mail: shanls@gsau.edu.cn
  • 作者简介:颜巧芳(1998-),女,硕士研究生,主要从事荒漠植物生理生态研究. E-mail: 15593826935@163.com
  • 基金资助:
    国家自然科学基金(32160253);甘肃省重点研发计划项目(22YF7FA117);甘肃省重大专项(22ZD6FA052);甘肃省自然科学基金(22JR5RA850);甘肃农业大学青年导师扶持基金(GAU-QDFC-2022-08)

Morphological characteristics of the leaves and roots of Caroxylon passerinum seedlings in response to drought-induced stress

YAN Qiaofang(),SHAN Lishan(),XIE Tingting,WANG Hongyong,SHI Yating   

  1. College of Forestry, Gansu Agricultural University, Lanzhou 730070, Gansu, China
  • Received:2023-05-15 Revised:2023-08-24 Online:2024-01-15 Published:2024-01-24

摘要:

探究荒漠植物叶片和根系形态特征对干旱胁迫的响应,有助于理解和预测气候变化条件下荒漠植物的生长调控策略。本研究以典型荒漠植物珍珠柴(Caroxylon passerinum)幼苗为研究对象,设置慢速干旱和快速干旱两种处理,测定叶片和根系相关的形态指标,分析了珍珠柴幼苗在不同干旱胁迫下叶片和根系的形态特征及两者之间的关系。结果表明:(1)随干旱胁迫时间延长,两种处理下的粗根直径减小,快速干旱处理的细根比根长、比根面积均减小,而快速干旱处理的叶组织密度增加,慢速干旱处理后粗根组织密度整体增大,而快速干旱处理则呈先增后减。(2)生长末期(54 d),两种处理下的粗根直径显著下降,快速干旱处理的肉质化程度和含水量分别显著低于对照和慢速干旱处理,胁迫37 d时,两种干旱处理下的珍珠柴粗根组织密度显著增大,并且慢速干旱大于快速干旱。(3)粗根比根长、粗根组织密度、细根比根长、比叶面积是珍珠柴性状变异的主要指标,相关性分析发现,珍珠柴叶片和根系共有29对性状之间相关联。综上所述,珍珠柴叶片、粗根、细根在不同水分处理下均表现出不同的适应策略,在两种干旱处理下珍珠柴通过减小粗根直径响应干旱胁迫。在快速干旱条件下,珍珠柴通过增大叶组织密度,减小细根比根长和比根面积等适应土壤水分亏缺。珍珠柴通过叶片、根系性状内部,叶片与根系性状之间的协同或权衡策略适应干旱。

关键词: 干旱胁迫, 形态特征, 叶片, 根系, 珍珠柴

Abstract:

Exploring the response of leaf and root morphological characteristics of desert plants to drought stress is helpful in understanding and predicting their growth regulation strategies under the climate change scenario. The seedlings of the typical desert plant Caroxylon passerinum were treated with slow and rapid drought, and the morphological indices of leaves and roots were measured. The morphological characteristics of leaves and roots of C. passerinum seedlings under drought stress were analyzed using slow and fast drought treatments. The results showed that: (1) with an extension in slow drought stress treatment time, thick-root diameter, fine-root specific length, and specific root area decreased; the leaf tissue density under rapid drought treatment increased; after slow drought treatment, the thick-root tissue density increased, while it increased at first and then decreased post-rapid drought treatment. (2) At the end of the growth period of 54 days, the thick-root diameter reduced markedly under the two treatments; the succulent degree and water content were significantly lower under rapid drought than those of the control and slow drought treatments, respectively. The thick-root tissue density of C. passerinum seedlings increased significantly after 37 days of stress, which was higher post-slow than fast drought. (3) The first four axes of principal components were mainly affected by coarse-root specific root length, thick-root tissue density, fine-root specific root length, and specific leaf area. Correlation analysis revealed that 29 pairs of characters were interrelated. In summary, the leaves, thick roots, and fine roots of C. passerinum showed varying adaptation strategies especially by reducing the diameter of thick roots under the two types of drought treatment. Under rapid drought, C. passerinum adapted to soil water deficit by enhancing the leaf tissue density and reducing fine-root specific root length and specific root area. Thus, C. passerinum seedlings adapt to drought through a coordination or tradeoff within and between leaf and root traits.

Key words: drought stress, morphological characteristics, leaf, root, Caroxylon passerinum