盐胁迫对甘草叶片光合色素含量和光合生理特性的影响

The Effect of Salt Stress on Content of Photosynthetic Pigment and Photosynthetic Characteristics in Glycyrrhiza uralensis Fisch

采用LI-6400便携式光合仪测定不同盐胁迫处理下甘草的光合作用生理指标,并采用分光光度法测定甘草叶片中光合色素的含量变化。结果表明:9 g/L NaCl的盐分胁迫降低了甘草叶片中叶绿素a(chl a)、叶绿素b(chl b)和类胡萝卜素(car)含量,增加了chl a/chl b;对胞间CO2浓度(Ci)的影响不显著;降低了净光合速率(Pn)、蒸腾速率(Tr)、气孔导度(Gs)等光合生理指标。3 g/L和6 g/L NaCl的盐分胁迫影响不显著。这说明适当浓度的盐胁迫可以影响甘草的光合生理作用,进而影响了甘草药材的产量。结果为探讨甘草对盐胁迫的适应机理提供了理论依据。

The photosynthetic characteristics of different salt stress treatments in Glycyrrhiza uralensis Fisch. were determined by LI-6400 portable photosynthesis instrument. The contents of photosynthetic pigments were measured by spectrophotometric method. The results showed that the cdntents of chlorophyll a （chl a）, chlorophyll b （chl b） and carotenoid （car） decreased, and the rate of chl a/chl b ascended under 9 g/L NaCl salt stress treatment. However, it showed no significant influence on the intercellular CO2 concentration （Ci）, but the net photosynthetic rate （Pn）, transpiration rate （Tr） and stomata conductance （Gs） decreased under 9 g/L NaC1 salt stress treatment. The 3 g/L and 6 g/L salt stress affected the photosynthetic characteristics insignificantly. It indicated that the proper concentration of NaCl salt stress could affect the photosynthesis of G. uralensis. Thus, the product of the licorice could be changed by salt stress. The results of present study affords theoretical basis for studying the mechanism of G. uralensis to salt stress.