NaCl胁迫下银水牛果光响应的研究

以不同浓度NaCl(0、200、400和600mmol·L-1)处理后的银水牛果盆栽幼苗为试验材料,利用Li-6400便携式光合测定系统对其光合生理特性的光响应进行研究。结果表明:不同的光合有效辐射(PAR)强度及土壤盐分浓度会对银水牛果的的净光合速率(Pn)、蒸腾速率(Tr)、气孔导度(Gs)、胞间CO2浓度(Ci)及水分利用效率(WUE)产生不同的影响。(1)随着盐浓度的增加和胁迫时间的延长,银水牛果幼苗叶片Gs、Pn、Tr均有下降趋势,但只有在600mmol·L-1NaCl处理下银水牛果的光合能力、Tr和Ci才显著降低;(2)当PAR为400～2000μmol·m-2·s-1、NaCl浓度低于600mmol·L-1时,银水牛果叶片具有较高的Pn和光能利用能力,且能维持较高的WUE。综上所述,银水牛果具有较强的耐盐性,对光辐射适应范围较广,适合在我国盐碱地和高原地区进行大面积的种植。

Study on light response of Shepherdia argentea seedlings to NaCl stress

With potted Shepherdia argenteas as test materials,we studied the light response of photosynthetic characteristics of them to the stress of different concentration(0,200,400 and 600 mmol·L-1) of NaCl by using Li-6400 portable photosyntometer.The results showed that different PAR intensities and salt concentration will make different effect to the Pn,Tr,Gs,Ci and WUE.(1)With the increase of salt concentration and duration of the stress,Gs,Pn and Tr showed a decrease tendency.But only under 600 mmolNaCl·L-1stress,its photosynthetic capacity,Pn and Gs were significantly declined.(2) When PAR was 400~2000 μmol/(m2·s) and concentration of NaCl was less than 600 mmol·L-1,Shepherdia argentea leaves had keeped Pn and WUE at high levels.It was concluded that Shepherdia argentea had strong salt tolerance and can adapt to wide range of PAR.So it can be planted widely in plateau area and saline regions of China.