芹菜对镉、铅胁迫的生理响应及抗氧化酶基因表达特性分析  

Physiological Responses to Cd,Pb Pollution and Expression Analysis of Antioxidative Genes in Celery

作　　者：肖旭峰[1] 解庆娓 蔡玲[2] 张明[2] 范淑英[1] 

机构地区：[1]江西农业大学农学院,江西南昌330045 [2]江西生物科技职业学院,江西南昌330008

出　　处：《核农学报》2017年第9期1864-1871,共8页Journal of Nuclear Agricultural Sciences

基　　金：江西省科技支撑计划项目(20122BBG70171);江西农业大学博士启动基金项目(3181)

摘　　要：为探讨芹菜在重金属镉、铅胁迫下的生理变化规律和抗氧化酶基因的表达特性,采用营养液培试验,研究镉(Cd)、铅(Pb)单一及复合胁迫对芹菜体内Cd/Pb富集、叶绿素、丙二醛(MDA)、谷胱甘肽(GSH)含量及抗氧化酶(SOD、POD)活性的影响,并用RT-q PCR技术检测了根尖细胞内抗氧化酶基因(Cat、Gpx、Mn-sod及Apx)的表达特性。结果表明,Cd^(2+)、Pb^(2+)单一及复合胁迫下芹菜茎叶中Cd^(2+)、Pb^(2+)含量均随胁迫浓度增大而逐渐增大,说明芹菜对Cd^(2+)、Pb^(2+)的吸收互为协同作用;6~8 mg·L-1Cd^(2+)和60~80 mg·L-1Pb^(2+)单一及复合处理对芹菜整个生长期内叶绿素、MDA、GSH含量及SOD、POD活性的影响均达到极显著水平(P<0.01);低浓度下单一及复合胁迫对叶绿素合成有促进效应,高浓度、长时间胁迫时,叶绿素含量显著降低;单一及复合胁迫对MDA、GSH含量及SOD、POD活性的影响均为Cd^(2+)-Pb^(2+)交互>Cd^(2+)>Pb^(2+),但单一Cd^(2+)浓度≥4 mg·L-1时,叶绿素含量大于Cd^(2+)-Pb^(2+)交互及单一Pb胁迫;Cd^(2+)、Pb^(2+)对芹菜叶POD和SOD活性的影响相似,均表现为"低促高抑";MDA、GSH含量随重金属浓度的升高而逐渐增加;单一及复合处理下Cat、Gpx、Mn-sod及Apx表达模式基本一致,其表达量的降低幅度为Cd^(2+)-Pb^(2+)交互>Cd^(2+)>Pb^(2+)。综上,Cd^(2+)、Pb^(2+)胁迫对芹菜的生理和抗氧化系统均造成了一定的损伤,二者具有协同性,这为江西省鄱阳湖区芹菜的安全生产提供了理论依据。To explore the physiological changes and expression analysis of antioxidative genes in celery （Apium graveolens） under Cd2＋ stress and Pb2＋ stress, a hydroponic experiment was conducted to investigate the effects of cadmium （ Cd2＋ ） and lead （Pb2＋ ） single and combined stresses of cadmium （Cd2＋ ） and lead （Pb2 ＋ ） on contents of Cd2＋ or Pb2＋, chlorophyll （Chl） , malondialdehyde （MDA） , glutathione （GSH） , and antioxidant enzyme activities （SOD and POD） , and were tested the expression of antioxidative genes with qRT-PCR in celery. The results showed that the concentration of Cd2 ＋ or Pb2＋ was promoted in single Cd2＋/Pb2＋ and Cd2＋ -Pb2＋ combined pollution. Compared with CK, the influences of Cd2＋ , Pb2＋ single andcombined stress on contents of Chl, GSH, MDA and activities of SOD and POD in the leaves were very significant difference （P 〈0.01） during the whole growth cycle of celery. Content of Chl was increased under the low concentrations of Cd2＋ , Pb2＋ and Cd2＋-Pb2＋ combined stress, but decreased under high concentrations and long time. The effects of Cd2＋ , Pb2＋ on MDA, GSH, SOD and POD followed the order of Cd2＋-Pb2＋ combined 〉 Cd2＋ 〉 Pb2＋, but after treated with the concentration of Cd2＋ I〉4 mg-L-t, the destructive effects on Chl showed Cd2＋ 〉 Cd2＋ -Pb2＋ 〉 Pb2 ＋ . The effects of Cd2 ＋ , Pb2 ＋ on activities of POD and SOD in celery leaf were similar. Both existed hormesis effect. Contents of MDA and GSH were promoted gradually with heavy metal concentration increasing. Expression patterns of Cat, Gpx, Mn-sod and Apx had the similar results under Cd2＋, Pb2＋ and Cd2 ＋ -Pb2＋ , and such reduction was Cd2＋ -Pb2＋ combined 〉 Cd2 ＋ 〉 Pb2＋ . In a conclusion, this study demonstrated that physiological system and antioxidant system of celery were damaged under Cd2＋ and Pb2＋ stress.

关 键 词：镉 铅 复合污染 芹菜 基因表达 

分 类 号：S636.3[农业科学—蔬菜学]