半红树植物海檬果幼苗耐盐性研究

温室内对半红树植物海檬果幼苗进行7个盐度(5、8、11、14、17、20、23 g.kg-1)的胁迫处理,并对各处理下海檬果的生长量、生物量、生理指标和光合速率进行测定,结合生理指标进行适应度分析。结果表明:海檬果的苗高增量、地径增量、叶片数增量,根、径、叶干质量及总生物量随着盐度的上升均呈下降趋势;单株叶干质量和总生物量均在对照处理下值最大,且显著高于其他处理,分别为最小值的23.07倍和4.74倍。低盐处理下海檬果光合作用较强,高盐抑制海檬果光合作用;随着盐度的增大,海檬果幼苗叶绿素总量、叶绿素A含量和根活力呈下降趋势,SOD、丙二醛和游离脯氨酸呈上升趋势。生理指标适应度分析表明,海檬果可耐受盐度为8 g.kg-1的处理,在盐度≥11 g.kg-1处理下呈不适应性生长。

Salt Tolerance of Semi-mangrove Plant Cerbera manghas Seedlings

Seedlings of Cerbera manghas were stressed by 7 salinities（5,8,11,14,17,20,and 23 g·kg-1） in the greenhouse.The increment,biomass,physiological indexes photosynthetic rate of seedlings of Cerbera manghas were determined with different salinity treatments,combined with the adaptability analysis of physiological indexes.Result shows that height increment,stem increment,leaf increment,dry weight of root,stem leaf and total biomass decreased with increase of the salt;leaf dry weight per plant total biomass which are all highest with CK treatment are higher than that of other treatments,being 23.07 4.74 times as large as the minimum value,respectively.The photosynthesis rate is high at the low-salt treatment,and is low at the high-salt treatment;superoxide dismutase,malondialdehyde and proline increase,but total chlorophyll,chlorophyll A and root activity decrease with increase of the salt.The adaptability analysis of physiological shows that Cerbera manghas grow normally when the treatment salt is 8 g·kg-1 and growth would be inhibited when the salinity is more than or equal to 11g·kg-1.