作 者 ：廖宝文*,邱凤英,张留恩,管伟,李玫
期 刊 ：生态学报 2010年 30卷 23期 页码：6363~6371
Keywords:mangrove plant, Bruguiera Sexangula var. rhynchopetala, salt stress, growth index, physiological index,
摘 要 ：在温室内采用自动潮汐模拟设备对尖瓣海莲幼苗进行为期160d的9个梯度（0、5、10、15、20、25、30、35、40）的盐胁迫处理，并测定幼苗的生长形态特征、生长量、生物量、光合速率、叶绿素含量、根活力及其它抗逆性生理指标。结果表明：随着盐度的增加，尖瓣海莲幼苗叶片内的超氧化物歧化酶（SOD）活性、游离脯氨酸、丙二醛及质膜透性均先减小后增大；尖瓣海莲幼苗的生长量、各器官生物量及总生物量均呈现出低盐促进生长，高盐抑制生长的现象；盐度为5的处理下生长最旺盛，盐度超过25后生长明显受到抑制，尖瓣海莲幼苗的总生物量最大值（盐度为5）比最小值（盐度为40）大25倍。主成分综合分析表明尖瓣海莲幼苗的适合生长盐度在25以下，在盐度为5时最适生长，当盐度超过25后，生长显著受限。
Abstract:The influences of different salinity (0、5、10、15、20、25、30、35、40) on the growth of mangrove species, Bruguiera sexangula var. rhynchopetala (Rhizophoraceae) seedlings were studied using the automatic tidal-simulation device in sand culture of greenhouse. The morphological and eco-physiological characteristics of B. sexangula var. rhynchopetala seedlings, e.g. biomass increment, biomass allocation, rate of photosynthesis, leaf chlorophyll content, root activity and other resistance physiological indexes, were determined in this study. The results showed the parameters associated with the height, stem base and blade growth of B. sexangula var. rhynchopetala seedlings varied widely under the treatments with different salinity. With the increase of salinity, the height of seedlings of the B. sexangula var. rhynchopetala decreased; the thickness of stem changed from thin to thick, then to thin again; the blade changed from slender and greenish to roomy and bottle-green, then to small and blackish green. At the same time, the activity of superoxide dismutase (SOD), the contents of proline and malondialdehyde, and the permeability of membrane in leaves decreased first and then increased. The growth rate, organ and total biomass increased at low salinity, but decreased at high salinity. The leaf area was large when the salinity was less than 25. In contrast, the leaf area decreased remarkably when the salinity was more than 25. The chlorophyll content increased first, then decreased, but increased again with the increase of salinity. The chlorophyll content under the treatment of 5-15 salinity was slightly higher than the treatment with no salt, and decreased slightly with the increase of salinity. In contrast, the chlorophyll content increased remarkably when the salinity was more than 30. The net photosynthetic rate and root activity were highest under 5 salinity, which were remarkably higher than other salinity treatments. The growth rate and biomass of B. sexangula var. rhynchopetala seedlings were all promoted under the treatment of low concentrations of salt, but all inhibited under the treatment of high concentrations of salt. The increment of the height, stem, and the number of the blade were highest when the salinity was 5, which were 10.8 times, 39.5 times and 19.6 times more than the minimum value when the seedlings were treated with 40 salinity respectively. The dry weight of leave, stem and root and the total biomass all increased first and then deceased with the increase of salinity. The dry weight of every organ of B. sexangula var. rhynchopetala seedlings were the most when the salinity was 5.The maximum of total biomass (5 salinity treatment) was about 25 times more than the minimum value (40 salinity treatment). The reaction of the underground part of B. sexangula var. rhynchopetala seedlings to salinity was more sensitive than the aboveground part. Analysis of principal component suggested the suitable salinity range for B. sexangula var. rhynchopetala seedlings are 0-25. The seedlings grew best under the 5 salinity treatment. While treating with >25 salinity, the growth of seedling was inhibited. This study provides a theoretical basis for the introduction, cultivation, genetic optimization and other further research of B. sexangula var. rhynchopetala.
全 文 ：