|
| 模拟酸雨与镉复合胁迫对玉米幼苗生理状况的影响 |
| Effects of simulated acid rain and Cd combined stress on physiological condition of maize seedling |
| 投稿时间：2018-01-26 |
| DOI：10.13254/j.jare.2018.0031 |
| 中文关键词: 酸雨，镉，萌发率，抗氧化酶，叶绿素含量 |
| 英文关键词: acid rain, cadmium, germination rate, antioxidant enzymes, chlorophyll content |
| 基金项目:国家自然科学基金项目（30740037）；国家公益性行业（农业）科研专项（201103024）；大气重污染成因与治理攻关项目（DQGG0107） |
|
| 摘要点击次数: 2310 |
| 全文下载次数: 2204 |
| 中文摘要: |
| 为探讨酸雨与重金属镉复合胁迫对作物（玉米幼苗）生长的影响机制，通过温室盆栽试验，分别进行了不同强度酸雨单一处理（酸雨pH分别为5、4、3、2）和不同强度酸雨（酸雨pH分别为5、4、3、2）与5 mg·kg-1 Cd2+的复合处理两个试验系列。采用分光光度法等对玉米幼苗生长指标（种子萌发率和幼苗株高、根长、株质量、根质量）、抗氧化酶（过氧化物酶POD、过氧化氢酶CAT、超氧化物歧化酶SOD、谷胱甘肽-S-转移酶GST）活性及叶绿素含量进行了测定。结果表明，与其各自空白对照（pH=6.5）相比，随酸雨强度的增大，单一及复合胁迫均导致玉米种子萌发率降低；而幼苗株高、根长和植株鲜质量则呈先促后抑的趋势。单一和复合胁迫酸雨强度敏感点分别为pH值等于3和4。两种胁迫SOD、POD活性均先升后降，单一和复合胁迫酸雨强度敏感点分别为pH值等于3和4；CAT、GST活性单一胁迫下表现为持续上升，复合胁迫下则先升后降，pH值等于3为其敏感点。两种胁迫的叶绿素含量均先升后降，单一和复合胁迫敏感点分别为pH值等于4和5。酸雨单一胁迫及其与重金属镉复合胁迫对玉米幼苗的影响均随酸雨强度的升高表现为双阶段性：低强度促进、高强度抑制。与同强度酸雨单一处理相比，Cd2+的存在，加大了酸雨单独存在时对玉米幼苗的损害作用。 |
| 英文摘要: |
| In order to investigate the underlying mechanisms of effects on crops growth(maize seeding) under the compound stress of acid rain and cadmium(Cd), the pot experiments in greenhouse were carried out, including a single treatment with one of the acid rain intensity sets(the pH of 5, 4, 3, 2, respectively) and a compound treatment together with one of the intensity sets of acid rain(pH=5, 4, 3, 2) and 5 mg·kg-1 of Cd2+. The maize seedling growth index(germination rate, plant height, root length, plant weight, root weight), antioxidant enzymes (peroxidase POD, catalase CAT, superoxide dismutase SOD and glutathione S-transferase GST) and chlorophyll content were determined by using the spectrophotometry, etc. Compared with the control pH=6.5, with the increase of acid rain intensity, single and compound stress both caused decreasing maize seeds germination rate, but the seedling plant height and weight, root length and weight showed the trend of promotion with low intensity and inhibition with high intensity. The acid rain intensity sensitive points of single and compound stress were pH 3 and pH 4, respectively. The activities of SOD and POD were increased first and then decreased, and the acid rain intensity sensitive points of single and compound stress were pH 3 and pH 4, respectively. For CAT and GST, single stress showed a continuous increasing trend; compound stress was first increased and then decreased, and acid rain intensity sensitive point was pH 3. The chlorophyll contents in two kinds of stresses were increased first and then decreased. The acid rain intensity sensitive points of single and compound stress were pH 4 and 5, respectively. It was concluded there were two phases for the effects of acid rain or/and Cd stress on growth index and enzyme activity in maize seedlings, which appeared a promotion at the low intensity and an inhibition at the high intensity. Compared with the single treatment, Cd2+ aggravated the damage of acid rain treatment alone. |
| HTML
查看全文
查看/发表评论 下载PDF阅读器 |
| 关闭 |
|
|
|
