增强UV-B辐射对高山植物歪头菜生长及内源激素变化的影响  

Changes of Endogenous Hormones in the Stress-response of Alpine Plant Vicia unijugaA.Br.to Enhanced UV-B Radiation

作　　者：强维亚[1] 蔡龙华[1] 韩瑜[1] 杨晖[2] 

机构地区：[1]兰州大学生命科学学院,草地与农业生态系统国家重点实验室,兰州730000 [2]甘肃省科学院生物研究所,兰州730000

出　　处：《西北植物学报》2013年第11期2241-2248,共8页Acta Botanica Boreali-Occidentalia Sinica

基　　金：国家自然科学基金项目(31070353);甘肃省科技支撑计划项目(0708NKCA077)

摘　　要：以青藏高原野生豆科牧草歪头菜(Vicia unijuga A.Br.)为材料,模拟甘南夏季晴朗无云天空平流层臭氧衰减9%的UV-B辐射强度(6.4kJ/m2),分析增强UV-B辐射条件下植株内源激素水平和全氮含量随时间变化及其与生长特性的关系。结果显示:(1)来自高寒地区野生歪头菜在增强UV-B辐射的最初阶段(10d左右)会产生对紫外胁迫的应激性响应,其内源生长激素吲哚乙酸(IAA)、玉米素(ZT)、赤霉素类(GAs)和6-苄氨基嘌呤(6-BA)含量水平以及全氮含量均明显高于对照,生长指标也相应升高。(2)随着处理时间延长,歪头菜内源生长激素含量开始迅速降低,并于处理后30d时降至最低,处理后40d时全氮含量也显著低于对照;同时,随着生长激素和全氮含量降低,植株生长也受到强烈抑制。(3)在处理后40d时歪头菜内源ABA才被检测到,说明细胞膜伤害发生的时间相对较晚。研究表明,来自高寒环境的植物种歪头菜经历长期自然选择和适应,形成了对强UV-B辐射的应激响应机制,使辐射伤害延迟,内源激素含量变化与该应激响应有密切关系。This study investigated the response features of alpine plant endogenous hormones, total nitrogen on time series and its relationship with growth under enhanced UV-B radiation by using the sample of Vicia unijuga collected from alpine meadow. The supplemental UV-B irradiation was 6.40 kJ/m2 per day that simulated 9 % stratospheric ozone depletion on clear summer solstice （Gannan, 3455 N, 2 900 m）, China. The results showed that：（1）The wild legume forage （Vicia unijuga） from alpine region could have stress response to enhanced UV-B radiation at the early stage of treatment. IAA, ZT, GAs, 6-BA levels and total nitrogen content increased and were significant higher than that of control at the ten days of treatment. Meanwhile,the plant growth also increased,the plant height and biomass were significant higher than that of control. （2）After 10 days of treatment,the hormones decreased rapidly and reached to the lowest level up to 30 days of treatment. The total nitrogen content also decreased continuously to reach at a significant lower lever than that of control from 10 to 40 days of treatment. The plant growth was inhibited with the reduction of hormones level and the total nitrogen content. （3）ABA has not been detected until the treatment for 40 days. It that the some plant severe environment the plant caused by suggested that the damage to membrane might be occurrence later. The study revealed species from alpine region have undergone natural selection and made adaptation to the for a long term,and developed the special response mechanism to delay the damages to UV-B radiation.

关 键 词：增强紫外线-B辐射 歪头菜 生长 内源激素 

分 类 号：Q945.78[生物学—植物学]