盐度对2种半红树植物生长及叶绿素荧光特性的影响

摘要

采用盆栽方法研究10个不同盐度水平下的海芒果、黄槿实生苗生长特性、叶绿素含量及叶绿素荧光参数变化情况。结果表明：随着盐度的增加，2种半红树植物的苗高、地径、根、茎、叶干重均逐渐变小；叶绿素含量呈波动式变化；除处理2的黄槿苗木（盐度为0．2％）外，叶绿素荧光参数PSII原初光能转化效率（E／功和PSII的潜在活性（FV／Fo）值均低于ck（清水）。以而／砌作为判断植株是否受胁迫的重要指标来看，黄槿在土壤盐度低于0．6％、海芒果在低于i．2％时表现出较好的耐受性。%The effects of salt of ten different concentrations on the growth, chlorophyll content and chlorophyll fluorescence of potted Hibiscus tiliaceus L. and Cerbera manghas L. were studied. The results showed that as the salinity increased, seedling height, basal diameter, root stem and leaf dry matter of the two semi-mangroves reduced gradually, and with fluctuated chlorophyll content. All treatments presented lower (Fv/Fo) and (Fv/Fo) than ck, except the treatment of H. tiliaceus L. seedling under 0.2% salinity where the efficiency of PSII primary photochemistry (FvFm), potential photochemical efficiency (FvFo) were slightly higher than ck. Using FJFm as the indicator to determine their salt tolerance, we can conclude that H. tilictceus L. can tolerate to the salinities below 0.6% and C. manghas L. can well withstand the salinities lower than 1.2%.