《植物生理学报》 2015, 51(11): 1846-1854

藜科植物藜与灰绿藜耐盐性的比较

王璐^*, 蔡明^*, 兰海燕^**

新疆大学生命科学与技术学院, 新疆生物资源基因工程重点实验室, 乌鲁木齐830046

通信作者：王；E-mail: Lanhaiyan@xju.edu.cn

摘　要：

通过比较盐胁迫下藜科植物藜与灰绿藜种子的萌发特性、植株形态及生理生化变化, 初步阐明了二者耐盐机制的差异。结果显示: (1)藜和灰绿藜种子萌发及早期幼苗生长均受低浓度NaCl (50、100 mmol•L^-1)的促进, 较高浓度NaCl (>200 mmol•L^-1)则产生抑制效应, 且藜受到的影响较灰绿藜更显著; (2)长期盐胁迫下, 两种植物的成株生长表型与对照无显著差异, 显示二者均能维持正常生长。与灰绿藜相比, 藜中氧自由基(O₂ ¯• )、过氧化氢(H₂O₂)及丙二醛(MDA)含量极显著升高, 表明其受到严重的氧化损伤。藜中4种抗氧化酶的活性除了过氧化氢酶(CAT)无明显变化外, 均随盐浓度升高而增加, 而灰绿藜中仅抗坏血酸过氧化物酶(APX)活性在高盐浓度下显著升高, 但仍显著低于藜, 显示抗氧化酶在藜应对盐胁迫产生的氧化毒害中发挥积极作用; 藜中3种抗氧化剂的含量除抗坏血酸(AsA)显著升高外均无明显变化, 三者总体水平均明显低于灰绿藜, 暗示抗氧化剂能有效应对灰绿藜受到的盐胁迫。藜中4种渗透调节物质含量除总蛋白降低外均显著升高, 灰绿藜中仅脯氨酸含量在高盐下显著增加, 表明渗透调节物质可能积极应对藜遭受的渗透胁迫。基于上述结果推测, 藜与灰绿藜均能耐受高盐胁迫, 但二者可能采取不同的应对策略。

关键词：藜; 灰绿藜; 盐胁迫; 种子萌发; 生理生化响应

收稿：2015-06-05   修定：2015-09-24

资助：国家自然科学基金(31260037、31060027)、新疆自治区优秀青年科技人才培养项目(2013721013)、新疆生物资源基因工程重点实验室开放基金(XJDX0201-2011-03)。

Comparison of Salt Tolerance between Chenopodium album and C. glaucum

WANG Lu^*, CAI Ming^*, LAN Hai-Yan^**

Xinjiang Key Laboratory of Biological Resources and Genetic Engineering, College of Life Science and Technology, Xinjiang University, Urumqi 830046, China

Corresponding author: WANG Lu; E-mail: Lanhaiyan@xju.edu.cn

Abstract:

Comparative study on salt tolerance between Chenopodium album and C. glaucum of Chenopodiaceae was performed by investigation of seed germination characteristics and the physiological and biochemical responses of plants under salt stress. Results showed that: (1) The germination and seedling growth of C. album and C. glaucum were promoted at 50 and 100 mmol•L^-1 NaCl, while inhibited at more than 200 mmol•L^-1 NaCl, and the performance of C. glaucum was better than that of C. album. (2) After long-term salinity treatment, the growth characters did not show significant change with rising salt concentration in both C. album and C. glaucum, indicating that these two species are able to grow normally under salt stress. The contents of O₂ ¯• , H₂O₂ and malondialdehyde (MDA) in C. album were significantly increased compared to that in C. glaucum, suggesting that C. album was severely injured by oxidative stress. The activities of four antioxidative enzymes in C. album were increased with rising salinity, except for catalase (CAT), whereas only ascorbate peroxidase (APX) activity was increased significantly in C. glaucum (still much lower than that in C. album), which means that these enzymes may play important roles in response to salt stress in C. album. The contents of three antioxidants showed no significant change in C. album, except for ascorbic acid (AsA), and the total level of the three antioxidants in C. album was all obviously lower than that in C. glaucum, which implies that these agents may make contributions in relieving of the salt stress in C. glaucum. The concentration of four osmoprotectants was increased significantly in C. album, except for total protein, while for C. glaucum only the proline increased significantly under high salt treatment, which suggests that these osmoprotectants may play important roles in osmotic balance in C. album under salt stress. Taken together, we speculate that both C. album and C. glaucum are all able to tolerate higher salinity, while they might employ different strategies in coping with salt stress.

Key words: Chenopodium album; Chenopodium glaucum; salt stress; seed germination; physiological and biochemical responses