2种杨树光合色素和抗氧化系统对UV-B与NaCl胁迫的响应  

Response of Photosynthetic Pigments and Antioxidant System to Ultraviolet-B Radiation and NaCl Stress in Two Species of Populus

作　　者：马瑄[1] 李涛涛[2] 赵亚男[1] 杨玉龙[1] 罗宇霞[1] 高永峰[1] 

机构地区：[1]西南科技大学生命科学与工程学院,四川绵阳621010 [2]中国科学院新疆生态与地理研究所,乌鲁木齐830011

出　　处：《西北植物学报》2015年第10期2042-2049,共8页Acta Botanica Boreali-Occidentalia Sinica

基　　金：国家自然科学基金(31270660);四川省青年科技基金(2014JQ0016);西南科技大学博士启动基金(14zx7157);西南科技大学研究生创新基金(15ycx091)

摘　　要：以胡杨和俄罗斯杨(黑杨杂交种)为材料,通过设置增强UV-B辐射、NaCl胁迫(100mmol/L NaCl)、复合胁迫(增强UV-B辐射+100mmol/L NaCl)及对照(不额外施加NaCl和UV-B)4组处理,研究2种杨树对UV-B辐射、NaCl胁迫及其复合胁迫的生理响应及其种间差异。结果显示:(1)增强UV-B辐射、NaCl胁迫及其复合胁迫下,2种杨树的叶绿素含量降低,叶绿素a/b比值减小,类胡萝卜素含量升高;叶片中的膜脂过氧化产物(MDA)和H2O2含量均显著升高;但在复合胁迫下,俄罗斯杨MDA含量要明显低于各单一胁迫处理,而胡杨MDA含量和2种杨树H2O2含量均介于2种单一胁迫处理之间。(2)在3种不同胁迫条件下,俄罗斯杨和胡杨叶片中过氧化物酶(POD)和过氧化氢酶(CAT)活性比对照显著升高,且POD活性在复合胁迫下最高。(3)2种杨树叶片中渗透调节物质(脯氨酸、甜菜碱、可溶性蛋白)含量在各胁迫条件下均比对照明显升高,且脯氨酸和可溶性蛋白含量在复合胁迫下最高;胡杨甜菜碱含量在3种胁迫条件下的升高幅度均远大于俄罗斯杨,而俄罗斯杨可溶性蛋白含量升高的幅度在增强UV-B辐射和复合胁迫下却明显高于胡杨。研究表明,增强UV-B辐射、NaCl胁迫及其复合处理对2种杨树生长均造成不同程度的胁迫伤害,但2种杨树在复合胁迫下表现出的抗氧化保护能力比在2种单一胁迫下更强,因而复合胁迫对2种杨树的伤害更小,UV-B辐射可能与NaCl胁迫相互拮抗最终减缓了对植物的伤害。In this study,we investigated that the effects of ultraviolet-B radiation and NaCl stress and their combined treatments on the antioxidant system and photosynthetic pigments in two species of poplar,Populus euphratica and Populus russkii（black poplar hybrids）,by setting four treatment groups including UV-B（enhanced UV-B radiation）,NaCl（100 mmol/L NaCl）,UV-B＋NaCl（enhanced UV-B radiation and100mmol/L NaCl）,CK（No extra NaCl and UV-B treatment）.The results show that：（1）under enhanced UV-B radiation and NaCl stress and their combined stresses,the content of chlorophyll of two species of Populus were decreased,the ratio of chlorophyll a/b was also decreased,but the content of carotenoid was increased.The contents of lipid peroxidation MDA and H2O2 in leaves of P.euphraticaand P.russkii wereboth significantly increased（P0.05）.However,under the combined stresses,the MDA content in leaves of P.russkii was significantly lower than each single stress,the MDA content in leaves of P.euphratica and the H2O2 content in leaves of P.euphraticaand P.russkii were between two single-stress.（2）The activities of POD and CAT in P.russkii and P.euphratica were all significantly increased under three different stresses,and POD activity was the highest under the combined stress.（3）The contents of osmotic protectants（such as proline,gylcinebetaine,soluble protein）in leaves of two species of populus were all significantly increased under three different stress conditions.Moreover,the contents of proline and soluble protein were the highest under the combined stresses.Compared with P.russkii,the content of gylcinebetaine in leaves of P.euphratica had larger increase in under three different stresses,while the content of soluble protein of P.russkii was significantly more than P.euphratica under enhancement of UV-B radiation and the combined stresses.In summary,two species of Populus were subject to different degrees of damage under three different stress conditions.But compared with two kinds of si

关 键 词：胡杨 俄罗斯杨 UV-B NACL胁迫 光合色素 抗氧化系统 

分 类 号：Q945.79[生物学—植物学]