摘要： 以马齿苋为材料采用温室盆栽法，研究了NaCl胁迫处理对其生长发育、品质积累、离子分布和叶绿素荧光特性的影响。结果表明，马齿苋种子发芽率、幼苗的鲜质量和株高在25～50 mmol/L NaCl胁迫时比对照略有下降，但其随着NaCl浓度的继续增加均显著降低。0～75 mmol/L NaCl处理浓度可提高马齿苋幼苗维生素C含量。盐胁迫影响植物组织的离子分布，Na⁺浓度持续增加，K⁺、Ca²⁺和Mg²⁺浓度下降。NaCl胁迫下，马齿苋幼苗叶片的初始荧光(Fo)、最大荧光(Fm)、PSⅡ潜在光化学效率(Fv/Fo)和PSⅡ实际光化学效率(ФPSⅡ)均降低。但在0～50 mmol/LNaCl浓度下，各荧光参数与对照差异不显著。可见，NaCl胁迫下，马齿苋产生了光合作用的光抑制伤害。低浓度下，植株能够较多地将光能用于光化学反应，光抑制程度较低，保持了较高的净光合速率，最终明显减轻盐胁迫对植株生长的影响。

关键词: 马齿苋, NaCl胁迫, 叶绿素荧光, 离子分布, 盐土农业

Abstract: Pot experiments were carried out to study the effects of NaCl stress on the growth， quality， ion distribution and chlorophyll fluorescence in Portulaca oleracea L． Eight different concentrations of NaCl were applied: 0，25， 50， 75， 100， 150， 200， 250 mmol /L． The results showed as follows: The germination rate， plant fresh weights andheights of seedlings had no difference with the control when the concentration of NaCl was 25 － 50 mmol /L， but decreased when the NaCl concentration was above 50 mmol /L． When the concentration of NaCl was 0 － 75 mmol /L，the Vc content of Portulaca oleracea L． increased． Increased treatment of NaCl induces increased of Na ⁺ and decreased of K ⁺ ， Mg²⁺ and Ca²⁺ ． Minimal fluorescence ( Fo) ， maximum fluorescence ( Fm) ， PSⅡ potential fluorescence efficiency ( Fv /Fo) and PSⅡ actual fluorescence efficiency( Ф PSⅡ ) all decreased when stressed by NaCl．And at low concentrations NaCl (0 － 50 mmol /L) stress， the fluorescence parameters changed slightly． So Portulacaoleracea L． was injured by photo-inhibition on NaCl stress， and at low concentrations， plant applied more light energyto photochemical reaction to maintain a high net photosynthetic rate， the degree of photo-inhibition was lower， therefor， NaCl stress had little effect on growth．

Key words: Portulaca oleracea L． , NaCl stress, Chlorophyll fluorescence, Ion distribution, Salty-soil agriculture

中图分类号: 

• S636.9