外源硅对盐胁迫下黄芩光合特性的影响

摘要

The net photosynthetic rate (Pn),stomatal conductance (Gs),limited stomates (Ls),intercellular CO2 concentration (Ci) and chlorophyll content of Scutellaria baicalensis seedlings treated with exogenous silicon solution under simulated NaCl stress are determined to discuss the effect of exogenous silicon on photosynthetic characteristics of S.baicalensis seedlings and to provide the scientific basis for cultivation and resistance breeding of S.baicalensis.Results:The salt stress inhibits the photosynthesis of S.baicalensis seedlings obviously.The Pn,Gs,Ls,Ci and chlorophyll content of S.baicalensis seedlings show the first rising and then declining trend with increase of exogenous silicon concentration.The Pn,Gs,Ls,Ci and chlorophyll content of S.baicalensis seedlings are 32.9 μmol/(m2 · s),0.458 mm ol/(m2 · s),0.479,250 μ mol/mol and 1.7 mg/g respectively when the exogenous silicon concentration is 0.05 g/L,which indicates that the photosynthesis of S.baicalensis seedlings reaches the maximum.%为黄芩种植和抗性育种提供依据,采用模拟盐胁迫和添加外源硅组合处理商洛1年生黄芩幼苗,通过测定净光合速率、气孔导度、孔限制数、细胞间CO2浓度和叶绿素含量等指标,探讨外源硅对盐胁迫下黄芩幼苗光合特性的影响.结果表明:盐胁迫导致商洛黄芩幼苗光合作用受到明显抑制,随着添加外源硅浓度的增加,黄芩幼苗的光合速率、气孔导度、孔限制数、细胞间CO2浓度和叶绿素含量均呈先升后降趋势,且各指标均在K2 SiO3浓度为0.05 g/L时达峰值,分别为32.9μmol/(m2·s)、0.458 mmol/(m2·s)、0.479、250 μmol/mol和1.7mg/g,光合作用最强.