干旱及复水对荒漠绿洲过渡带一年生草本植物生长及生理特性的影响  

Effects of drought stress and rehydration on the growth and physiological characteristics of annual herbaceous plants from a desert-oasis ecotone

作　　者：曾露婧 王国华 ZENG Lu-jing;WANG Guo-hua(College of Geographical Sciences,Shanxi Normal University,Taiyuan 030031,China;Linze Inland River Basin Research Station,Northwest Institute of Eco-Environment and Resources,Chinese Academy of Sciences,Lanzhou 730010,China)

机构地区：[1]山西师范大学地理科学学院,山西太原030031 [2]中国科学院西北生态环境资源研究院临泽内陆河流域研究站,甘肃兰州730010

出　　处：《草业学报》2024年第5期41-57,共17页Acta Prataculturae Sinica

基　　金：国家自然科学基金(42171033);山西省高等学校科技创新项目(2019L0457,2019L0463);中国科学院沙漠和沙漠化重点实验室开放基金项目(KLDD-2020-05)资助。

摘　　要：一年生草本植物种群组成荒漠与绿洲生态系统的恒有性植物层片,在防风固沙和保护绿洲生态系统稳定方面具有重要的作用。本研究选取河西走廊荒漠绿洲过渡带人工林下典型5种一年生草本植物虎尾草、狗尾草、白茎盐生草、沙米和雾冰藜为研究对象,采用盆栽试验模拟干旱胁迫及复水,测定5种植物幼苗根系和叶片的生长(株高、根体积、根系平均直径、根系总表面积、根系总长和根系干重)与生理指标(根系活力、光合色素、丙二醛、渗透调节物质和抗氧化酶活性)的变化特征和规律,分析其对干旱环境的适应能力。研究结果表明,轻度干旱胁迫(土壤水分相对于CK减少2%)对5种一年生草本植物生长影响较小,甚至有一定的促进作用;中度(土壤水分相对于CK减少4%)和重度(土壤水分相对于CK减少6%)干旱胁迫下植物生长受到明显抑制。随着干旱胁迫程度的加剧,5种植物根系和叶片的丙二醛、过氧化物酶活性和渗透调节物质含量呈上升趋势;而根系活力呈下降趋势。禾本科一年生草本植物虎尾草和狗尾草根系酶活性(超氧化物歧化酶)随干旱胁迫程度的加剧呈持续增加的趋势;藜科一年生草本植物沙米和雾冰藜随干旱胁迫程度的加剧表现出先增加后下降的趋势。复水处理后,5种植物的生长和生理均得到不同程度的补偿,且根系的恢复能力高于叶片,浅根系植物的恢复能力优于深根系的。5种一年生草本植物的抗旱性具有显著差异,依次为狗尾草>白茎盐生草>雾冰藜>虎尾草>沙米。In desert-oasis ecotones,many annual herbaceous plant populations form permanent plant synusiae,which play important roles as windbreaks and in sand fixation,thereby protecting the stability of the oasis ecosystem.In this study,we selected Chloris virgata,Setaria viridis,Halogeton arachnoideus,Agriophyllum squarrosum,and Bassia dasyphylla as five typical annual herbaceous plants under artificial forests in a typical desert-oasis ecotone in the Hexi Corridor,and conducted pot experiments with simulated drought and rehydration treatments.We measured the changes in root and leaf growth traits(i.e.,plant height,root volume,average root diameter,total root surface area,total root length,and root dry weight)and physiological characteristics(i.e.,root activity,contents of photosynthetic pigments,malondialdehyde,osmotic adjustment substances,and antioxidant enzyme activity)of seedlings of the five plants to analyze their adaptive strategies to drought stress.The results showed that light drought stress(i.e.,soil moisture decreased by 2%compared with the control)had no significant negative effect on the growth of the five annual herbaceous plants,but promoted their growth to some extent.Plant growth was significantly inhibited under moderate(soil moisture decreased by 4%)and severe(soil moisture decreased by 6%)drought stress.The contents of malondialdehyde and osmoregulatory substances and the activity of peroxidase in the roots and leaves increased with increasing severity of drought stress;but the root activity decreased significantly.The activity of superoxide dismutase in the roots of the annual Gramineae C.virgata and S.viridis increased with increasing severity of drought stress;however,its activity in the roots of A.squarrosum and B.dasyphylla(Chenopodiaceae)initially increased and then decreased with increasing severity of drought stress.Upon rehydration treatments,the growth and physiology of all five plant species were compensated to different degrees.Roots recovered better than did leaves,and shallow-rooted pl

关 键 词：一年生草本植物 干旱胁迫 复水 生长 生理特性 

分 类 号：Q948[生物学—植物学]