Salt response of the freshwater microalga Scenedesmus obliquus(Turp.)Kutz is modulated by the algal growth phase

作     者：Taha Mohamed EL-KATONY Magda Faiz EL-ADL Taha Mohamed EL-KATONY;Magda Faiz EL-ADL

作者机构：Department of Botany and MicrobiologyFaculty of ScienceDamietta UniversityNew Damietta City 34517Egypt 

出 版 物：《Journal of Oceanology and Limnology》 (海洋湖沼学报（英文）)

年 卷 期：2020年第38卷第3期

页      面：802-815页

核心收录：

学科分类：09[农学] 0903[农学-农业资源与环境] 

主　　题：carbohydrates growth phase minerals protein salt stress Scenedesmus obliquus 

摘      要：Growth and biochemical responses of the coenobial green alga Scenedesmus obliquus to salinity stress were monitored across different phases of *** alga was cultured on BG11 growth medium and subjected to 0,30,100,and 200 mmol/L NaCl for a period of 20 d,during which algal cultures were harvested at 4-d *** salinity-induced inhibition of algal growth was accompanied with prolongation of timing of the different growth *** sharp and progressive salinity-induced inhibition of algal growth rate during the early phase of growth points to salt shock but moderation of inhibition at the subsequent stages of growth means algal acclimation to *** concentrations of chlorophylls a and b,soluble sugars,proteins as well as those of K+and Na+in the alga exhibited peaks at the initiation of the exponential phase of growth,with increasing magnitude in proportion to the increase in the level of ***,whereas soluble sugars of the alga peaked at initiation of the exponential phase,starch concentration progressively increased with culture age,reaching saturation towards the stationary *** the salinity-induced increase in soluble sugars was most evident at the early stages of growth the reverse was true for *** present results point to fast acclimation of *** to salt stress post a brief salt shock,utilizing soluble sugars,K+and Na+for osmotic *** salinity from 0 to 200 mmol/L NaCl led to progressive increase in soluble sugars,proteins,K+and Na+concentrations of the algal cells,particularly at the early stages of ***,the salinity-induced increase in chlorophyll concentration approached a limit at 100 mmol/L NaCl whereas that in starch concentration was more evident at the later stages of growth.