NaCl胁迫对珊瑚菜叶绿素荧光特性的影响

以野生濒危植物珊瑚菜(Glehnia littoralisFr.Schmidt ex Miq.)幼苗为试材,通过水培试验研究了100、200和300 mmol?L-1NaCl处理对其生长状态、叶绿素含量以及叶绿素荧光动力学参数的影响,以探讨珊瑚菜的耐盐机制和耐盐能力.结果显示,随着NaCl处理浓度和时间的增加,珊瑚菜生长受到抑制程度逐渐加剧;其叶片叶绿素a、叶绿素b、总叶绿素含量均表现不同程度的降低,而Chl a/b值却呈先下降后上升的变化趋势,并以300 mmol?L-1NaCl处理变化最为明显;同时,其PSⅡ的最大光化学效率(Fv/Fm)和捕获的激子将电子传递到电子传递链中超过QA的其他电子受体的概率(ETo/TRo)均表现不同程度的降低,而光合机构电子传递的量子产额(ETo/ABS)、最大捕光效率(TRo/ABS)均呈先下降后上升的变化趋势,但单位反应中心以热能形式耗散的能量(DIo/CSo)则先上升后下降.研究表明,珊瑚菜对NaCl胁迫具有一定的适应调节能力,可以耐受200 mmol?L-1NaCl以下的盐胁迫,而300 mmol?L-1NaCl处理就会对其光合系统造成一定的损伤,明显抑制其正常生长.

Effects of NaCl on Chlorophyll Fluorescence in Glehnia littoralis Fr.Schmidt ex Miq.

This paper studied the water planting treatment with 100,200 and 300 mmol·L-1 NaCl) on the growth status,chlorophyll content and chlorophyll fluorescence kinetics of endangered species of wild Glehnia littoralis seedlings to explore salt tolerance mechanisms and ability of G.littoralis.The results showed that with the concentration and time increasing,the growth of G.littoralis was restrained,chlorophyll a,chlorophyll b,total chlorophyll,PSⅡ reaction center of the maximal photochemical efficiency(Fv/Fm) and the captured electron transferred to the electron transport chain surpassed the other electron acceptor QA probability(ETo/TRo) all represented different degree of reduced,Chl a/b value,the quantum yield of electron transported in photosynthetic apparatus(ETo/ABS),and maximum quantum yield for primary photochemistry(TRo/ABS) were first decreased and then increased,and the unit reaction center of energy dissipated as heat was increased and then decreased.The research showed that G.littoralis had a certain ability to adapt NaCl stress,which could withstand 200 mmol·L-1 NaCl concentration where as 300 mmol·L-1 concentration of NaCl treatments caused certain damage to photosynthetic systems.