共生与非共生爪哇伪枝藻对高温胁迫的响应  

RESPONSE TO HIGH TEMPERATURE STRESS IN SYMBIOTIC AND FREELIVING SCYTONEMA JAVANICUM

作　　者：雷亚萍[1] 许丽红[1] 曾臻[1] 吴丽[1] 

机构地区：[1]武汉理工大学资源与环境工程学院,武汉430070

出　　处：《水生生物学报》2017年第3期671-676,共6页Acta Hydrobiologica Sinica

基　　金：国家自然科学基金(31300100)资助~~

摘　　要：研究以自由生长的爪哇伪枝藻(Free-living S.javanicum,fs)和分离自地衣的爪哇伪枝藻(Symbiotic S.javanicum,ss)为研究对象,探究了不同生长状态爪哇伪枝藻对高温(45℃)胁迫的响应。结果发现在高温胁迫下,爪哇伪枝藻光合活性、叶绿素a及类胡萝卜素含量下降;丙二醛(MDA)、胞外多糖及可溶性蛋白含量上升。在高温处理下,与fs相比,ss光合活性下降较慢,且高温处理后ss的叶绿素a及类胡萝卜素含量也明显高于fs。高温处理下,与fs相比,ss的MDA含量和增长速度均较低;并且在面临高温胁迫时,ss能够更快的分泌胞外多糖和可溶性蛋白质,从而在一定程度上达到自我保护的目的。研究结果表明,在暴露于高温胁迫时,相较于自由生长状态,来自地衣的爪哇伪枝藻具有更高的自我保护效率。Biological soil crusts （BSCs） are widely distributed in global arid and semi-arid environment, where hightemperature stress is one of the critical environmental factors to control the survival of algae. As a common species inBSCs, Scytonema javanicum appears in alga crust stage as free-living form and in lichen crust as symbiotic form to regulate the formation and development of BSCs. This study explored the effect of high temperature stress （45℃） on symbio-tic （ss） and free-living S. javanicum （fs）. The results showed that high temperature stress declined the photosyntheticactivity more dramatically in ss compared with in fs, and high temperature stress induced a higher biomass in ss compared with in fs. Compared with fs, ss had lower growth rate and MDA content, and faster extropolysaccharides-released and soluble protein- to protect from damages. The results showed that, compared with free-living form, the S.javanicum from lichens had higher self-protection efficiency when exposed to high temperature.

关 键 词：生物结皮 爪哇伪枝藻 自由生长 共生 高温胁迫 生理生化 

分 类 号：Q142[生物学—生态学]