不同光照强度下三角叶滨藜光合作用对盐激胁迫的响应  

The Photosynthetic Response of Atriplex triangularis to Salt-shock under Varied Light Intensity

作　　者：柏新富[1] 朱建军[1] 张萍[1] 蒋小满[1] 

机构地区：[1]鲁东大学生命科学学院,山东烟台264025

出　　处：《西北植物学报》2008年第9期1823-1829,共7页Acta Botanica Boreali-Occidentalia Sinica

基　　金：国家自然科学基金(30471044);鲁东大学科研基金(20053304)

摘　　要：以溶液培养的三角叶滨藜植株为材料研究了不同光照条件下其叶片光合作用对盐（NaCl）激胁迫的即刻反应及变化规律.结果表明,三角叶滨藜光合作用对盐激胁迫的响应有8 min左右的滞后期.在光照强度为100μmol·m^-2·s^-1和100 mmol·L^-1浓度NaCl共同作用下,三角叶滨藜叶片净光合速率略有上升;但随NaCl浓度和光照强度进一步增加,其净光合速率呈下降趋势,且光照越强,盐胁迫导致的净光合速率下降幅度越大.同时,弱光下或强光低浓度NaCl胁迫下,盐激胁迫导致的净光合速率下降主要是气孔限制引起的;而强光下,高浓度的NaCl胁迫导致的净光合速率下降在盐激胁迫处理的前30-40 min主要由气孔限制引起,40 min后则主要由非气孔限制引起.可见,不同光照强度和NaCl浓度胁迫下三角叶滨藜叶片光合作用响应规律不同,引起净光合速率下降机制各异.The immediate and follow-up change in photosynthesis in leaves of saltbush （Atriplex triangularis） subjected to NaCl shock under different light intensity were investigated by using saltbush seedlings with solution culture. The results showed that there was a lag of ca. 8 rain in the photosynthetic response to the onset of salt shock. Up to a light intensity of 100 μmol·m^-2·s^-1 and up to a NaCl concentration of 100 mmol·L^-1 exerted concomitantly to the plant,the net photosynthetic rate showed a tendency of increase. Future increase in light intensity and salt concentration resulted in the reduction in the net photosynthetic rate,and the higher light intensity, the higher the salt-induced net photosynthetic reduction. The results also indicated that under lower light intensity or lower levels of NaCl stress, the salt-induced net photosynthetic reduction in Atriplex triangularis was predominantly due to the limit of stomata aperture; while under high light intensity,the net photosynthetic reduction induced by high salinity in Atriplex triangularis was mainly due to the limit of stomata aperture at the initial 30-40 min following the onset of salt stress,then the non-stomata factors prevailed over the stomata effect 40 rain after the onset of salt stress. It is therefore concluded that Atriplex triangularis responds differently to different light and salt levels in terms of photosynthesis, and the mechanisms of net photosynthetic reduction is different as well in different conditions.

关 键 词：三角叶滨藜 盐激 光合作用 气孔限制 非气孔限制 

分 类 号：Q945.78[生物学—植物学]