珍稀植物长叶红砂与近缘种红砂水分特征比较  

Comparative analysis of water relation parameters between rare and relict plant Reaumuria trigynaand its related congener Reaumuria soongorica

作　　者：石松利[1,2] 周健华[1] 舒红英[1] 王迎春[1] 

机构地区：[1]内蒙古大学生命科学学院,呼和浩特010021 [2]包头医学院药学系,内蒙古包头014060

出　　处：《内蒙古大学学报（自然科学版）》2010年第3期323-330,共8页Journal of Inner Mongolia University：Natural Science Edition

基　　金：内蒙古自治区自然科学基金重大项目(200711020501);国家基础科学人才培养基金项目(J0730648)

摘　　要：运用PV技术对我国特有珍稀孑遗植物长叶红砂和生长于同一生境中的近缘种红砂的水分关系参数(Ψssat、Ψtslp、AWC、Va/Vo)进行了测定,并从水分生理生态角度对这两种耐盐强旱生小灌木抗逆性、适应性进行了比较研究.结果表明:1)与其它荒漠旱生植物相比,长叶红砂、红砂Ψssat值和Ψtslp值均很低,具有很强的保持最大膨压和维持低水势的能力,其耐旱机理主要表现为增加细胞质浓度的渗透调节,反映了这两种强旱生耐盐植物在水分参数上的特殊性.2)土壤盐分越高,植物组织Ψssat值和Ψtslp值越低,长叶红砂和红砂能够通过提高体内盐分含量而降低渗透势,提高渗透调节能力以适应不同的盐渍生境,在重盐土上生存的红砂体内具有较大的质外体水含量,抗脱水能力较强.3)同一生境下,红砂的Ψssat值和Ψtslp值均低于长叶红砂,AWC值和Va/Vo值均高于长叶红砂,红砂通过渗透调节控制蒸腾失水率的能力强于长叶红砂,其抗逆性强于长叶红砂.二者在长期自然选择下对环境的适应能力产生分化,红砂对可变环境的适应能力更强,长叶红砂生理生态方面的竞争力和内在适应力相对较弱.Measurement of several water relation parameters（Ψs^ats、Ψt^lps、AWC、Va/Vo）is made by PV technique in rare and relict plant Reaumuria trigynaand its related congener Reaumuria soongoricafrom the same habitat,and a comparative analysis of stress resistance and intrinsic adaptation in two halophyte and xerophytic shrubs in hydro-physiology is also made.Following results have been obtained.1）Compared with other xerophyte plants,the water parameters of halophyte and xerophytic shrubs R.trigynaand R.soongoricaappeared particularity,which have strong ability of maintaining high turgor and low water potential with very low values of Ψs^ats and Ψtlps.They could adjust osmosis by improving the concent ration of cellular solute.2） The maximum osmotic potential at water saturation point（Ψsats）and the osmotic potential when a plasmolysis just emerges（Ψtlps）decreased as the salinity of soil increase,they can enhance osmotic adjustment ability by reducing the osmotic potential to adapt different saline habitat.R.soongoricain strongly Salined Soil is of stronger ability of holding water（higher AWC）.3） Under the identical habitat,R.soongoricahas lowerΨsats,Ψtlps,and higher AWC,Va/Vothan R.trigyna.The ability of controlling transpiration dehydration by adjusting osmosis was stronger than R.trigyna.The ability of stress resistance in R.trigynawas stronger than R.soongorica.It indicated that two plant species have the differentiation under the long-term natural selection to the environment adaptiveness.It showed that intrinsic adaptation,competition of R.trigynawere weaker than R.soongorica.

关 键 词：长叶红砂 红砂 PV技术 水分关系参数 抗逆性 

分 类 号：Q945.17[生物学—植物学]