干旱区研究 ›› 2021, Vol. 38 ›› Issue (1): 198-206.doi: 10.13866/j.azr.2021.01.21

• 植物与植物生理 • 上一篇    下一篇

不同土壤水分条件下沙生柽柳(Tamarix taklamakanensis)的生理生化特征及适应性

苏志豪1(),周晓兵1,姜小龙2,王留强3,公延明1,康晓珊1   

  1. 1.中国科学院新疆生态与地理研究所荒漠与绿洲生态国家重点实验室,新疆 乌鲁木齐 830011
    2.中南林业科技大学林木遗传育种实验室,湖南 长沙 410004
    3.中国林业科学研究院林业研究所林木遗传育种国家重点实验室,北京 100091
  • 收稿日期:2020-04-03 修回日期:2020-05-18 出版日期:2021-01-15 发布日期:2021-03-05
  • 作者简介:苏志豪(1981-),男,副研究员,主要从事植物保护生物学研究. E-mail: suzh@ms.xjb.ac.cn
  • 基金资助:
    国家自然科学基金(U1803103);国家自然科学基金(31770703);中国科学院先导A项目(XDA2005020402)

Physiological and biochemical characteristics and adaptability of Tamarix taklamakanensis in different ecological habitats in the Tarim Basin

SU Zhihao1(),ZHOU Xiaobing1,JIANG Xiaolong2,WANG Liuqiang3,GONG Yanming1,KANG Xiaoshan1   

  1. 1. State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, Xinjiang, China
    2. Laboratory of Forestry Genetics, Central South University of Forestry and Technology, Changsha 410004, Hunan, China
    3. State Key Laboratory of Tree Genetics and Breeding, Research Institute of Forestry, Chinese Academy of Forestry, Beijing 100091, China
  • Received:2020-04-03 Revised:2020-05-18 Online:2021-01-15 Published:2021-03-05

摘要:

沙生柽柳(Tamarix taklamakanensis)是我国特有种,是塔里木盆地流动沙丘上最抗旱树种,对固沙造林和荒漠化防治起到非常重要的作用。通过测定沙生柽柳种群在3种不同生境(沙漠公路绿化带、河床砾质荒漠、流动沙丘)的叶片含水量、叶绿素含量、抗氧化酶活性及渗透调节物质含量,探讨了沙生柽柳在不同生境下的生理生化特征及对荒漠极端干旱环境的适应机制。结果表明:随着土壤干旱程度的加剧,沙生柽柳叶片相对含水量逐渐下降;超氧化物歧化酶(SOD)活性、过氧化物酶(POD)活性、总抗氧化能力(T-AOC)逐渐升高;过氧化氢酶(CAT)与硝酸还原酶(NR)活性逐渐降低;种群叶片内可溶性蛋白呈上升趋势。在最为干旱的流动沙丘,种群叶片叶绿素a含量、可溶性糖含量最高。在干旱胁迫条件下,沙生柽柳种群主要通过增高SOD活性、POD活性、总抗氧化能力及降低过氧化氢酶(CAT)、硝酸还原酶(NR)含量以维持活性氧代谢平衡;同时,通过大量积累渗透调节物质可溶性糖、可溶性蛋白、丙二醛以维持高渗透调节能力抵御干旱环境胁迫。

关键词: 沙生柽柳, 抗氧化酶活性, 渗透调节物质, 生态适应性

Abstract:

Tamarix taklamakanensis is a tree endemic to China and it is the most drought-resistant species in drifting sand dunes within the Tarim Basin. It plays an important role in sand fixation and desert prevention. We selected populations in three different habitats (green belt near the desert road, gravelly desert in riverbed, and drift sand dunes) to quantify the water status, chlorophyll contents, antioxidant enzyme activities, and osmotic adjustment substances contents. We evaluated the species’ physiological and biochemical characteristics in different habitats and its adaptive mechanisms to deal with extreme drought conditions. In soils with low moisture content, superoxide dismutase (SOD) activities, peroxidase (POD) activities, total antioxidant capacity, and soluble protein contents increased, whereas catalase (CAT) and nitrate reductase (NR) activities decreased. In the driest drift sand dune habitat, the population had highest chlorophyll a and soluble sugar contents. Under drought stress, T. taklamakanensis increased SOD and POD activities and total antioxidant capacity, while it decreased CAT and NR activities to maintain the metabolic balance of reactive oxygen. It increased soluble protein, soluble sugar, and malondialdehyde to maintain high osmotic adjustment ability for resisting drought environments.

Key words: Tamarix taklamakanensis, antioxidant enzyme activities, osmotic adjustment substances, ecological adaptability