PEG胁迫对扭果花旗杆幼苗生理特性和染色体行为的影响  

Effect of PEG Stress on Physiological Characteristics and Chromosomal Behavior of Dontostemon elegansMaxim Seedlings

作　　者：邹丽媛 马薇 葛风伟[1] Zou Liyuan;Ma Wei;Ge Fengwei(Key Laboratory of Plant Stress Biology in Arid Land,Key Laboratory of Special Environment Biodiversity Application and Regulation in Xinjiang,Xinjiang Key Laboratory of Special Species Conservation and Regulatory Biology,College of Life Science,Xinjiang Normal University,Urumqi,830054)

机构地区：[1]新疆师范大学生命科学学院,新疆特殊环境物种保护与调控生物实验室,新疆特殊环境物种多样性应用与调控重点实验室,干旱区植物逆境生物学实验室,乌鲁木齐830054

出　　处：《分子植物育种》2021年第14期4812-4819,共8页Molecular Plant Breeding

基　　金：新疆维吾尔自治区高校科研计划科学研究重点项目(20160623142231897);新疆师范大学博士启动基金(XJNUBS1541);新疆师范大学新疆特殊环境物种保护与调控生物学实验室开放课题基金(XJDX1414-2016-02);2019年自治区大创项目(S201910762029X)共同资助。

摘　　要：扭果花旗杆(Dontostemon elegans Maxim)是新疆达坂城荒漠地区广泛分布的旱生植物,具有极强的抗旱性,在维持荒漠植被的稳定性中发挥重大作用。本研究采用不同浓度梯度的PEG-6000溶液模拟干旱胁迫处理扭果花旗杆幼苗,并测定其生理指标及细胞学特征,分析干旱胁迫对扭果花旗杆幼苗生理特性及根尖细胞染色体行为的影响。结果表明:(1)低浓度PEG(≤20%)处理扭果花旗杆幼苗,其超氧化物歧化酶(SOD)、过氧化物酶(POD)和过氧化氢酶(CAT)的活性4 d之内呈现线性上升,之后下降;25%PEG处理时,3种酶活性在前3 d达到峰值,之后迅速下降;(2)游离脯氨酸(PRO)、可溶性蛋白(SP)、丙二醛(MDA)的含量均随着胁迫时间的增加呈现先上升后下降的趋势;(3)PEG胁迫处理抑制扭果花旗杆种子根尖细胞的有丝分裂,随PEG胁迫浓度的增加和时间的延长抑制作用更加明显;同时研究发现种子根尖细胞染色体畸变率、微核率与PEG浓度呈正相关。研究结果说明在干旱胁迫时扭果花旗杆经过一系列的生理生化变化来适应逆境,可为扭果花旗杆抗旱研究提供理论参考。Dontos temon elegans Maxim is a xerophyte widely distributed in the desert area of Dabancheng,Xinjiang. It has strong drought resistance and plays an important role in maintaining the stability of desert vegetation. In this study, PEG-6000 solution with different concentration gradients was used to simulate the drought stress treatment of Dontostemon elegans Maxim seedlings. The physiological and cytological characteristics of Dontostemon elegans Maxim seedling were measured, and the effects of drought stress on the physiological characteristics of Dontostemon elegans Maxim seedlings and the chromosomal behavior of root tip cells were analyzed. The results showed that:(1) the activities of superoxide dismutase(SOD), peroxidase(POD) and catalase(CAT) of Dontostemon elegans Maxim seedlings increased linearly within 4 days after being treated with low concentration PEG(≤20%), and then decreased rapidly after being treated with 25% PEG.(2) The contents of free proline(PRO), soluble protein(SP) and malondialdehyde(MDA) increased first and then decreased with the increase of stress time.(3) The results showed that PEG stress inhibited the mitosis of the root tip cells of Dontostemon elegans Maxim, and the inhibition was more obvious with the increase of PEG stress concentration and the extension of time. The results showed that the Dontostemon elegans Maxim had a series of physiological and biochemical changes to adapt to the adversity, which could provide a theoretical reference for the study of drought resistance of Dontostemon elegans Maxim.

关 键 词：扭果花旗杆 干旱胁迫 抗氧化酶 染色体行为 

分 类 号：Q945.78[生物学—植物学]