黄瓜发育早期对邻苯二甲酸二(2-乙基)己酯(DEHP)胁迫的亚显微结构及生理响应比较研究  

A Comparative Study of Leaf Ultrastructure and Physiological Changes of Cucumber Seedlings Grown Under Stress of Di-2-ethylhexyl Phthalate(DEHP)

作　　者：张颖[1] 段淑伟 王蕾[1] 张惠[1] 杜娜[1] 

机构地区：[1]东北农业大学资源与环境学院,哈尔滨150030

出　　处：《农业环境科学学报》2014年第9期1706-1711,共6页Journal of Agro-Environment Science

基　　金：国家高技术研究发展计划("863"计划)"设施农业土壤酞酸酯污染与生物修复研究(2012AA101405)

摘　　要：通过盆栽试验比较分析黄瓜发育早期叶片亚显微结构对不同浓度(0、6、10、20、40mg·kg-1)DEHP胁迫的响应。透射电镜观察发现,DEHP胁迫对黄瓜叶肉细胞亚显微结构造成了不同程度损伤,随着DEHP处理浓度的增大,液泡逐渐膨大,细胞的膜结构消失。当DEHP达到10mg·kg-1时,线粒体嵴数目减少,线粒体呈空泡状;同时叶绿体类囊体膨胀,直至破裂,叶绿体被膜受到破坏,叶绿体中淀粉粒明显膨大、增多;当DEHP达到20mg·kg-1时,细胞核核仁解体,染色质凝聚,核膜断裂。与亚显微观察结果相一致,随着DEHP浓度的增加,黄瓜叶片中的叶绿素a、b和总叶绿素含量均呈现下降的趋势,而过氧化氢(H2O2)含量则呈上升趋势,表明DEHP胁迫通过产生过量的活性氧破坏黄瓜叶片正常的亚显微结构。Due to its wide uses, di-2-ethylhexyl phthalate（DEHP）is everywhere in the environment. It has been detected in most agricultural soils in China. It may affect the growth and development of plants. A comparative analysis of the influence of different concentrations of DEHP（0, 6, 10, 20, 40 mg·kg^-1）on ultrastructure of cucumber seedling leaves at the early growth stages was performed in a pot experiment. Transmission electron microscope（TEM）was employed to examine the effects of DEHP on the ultrastructure of the leaves. Increasing DEHP concentrations led to expanded vacuoles and collapsed structure of cell membrane. At 10 mg·kg^-1of DEHP, mitochondria became vacuolized, and the number of mitochondrial cristae decreased. Meanwhile, thylakoids of chloroplast swelled gradually, chloroplast envelopes were destroyed, and the quantity and volume of starch grains in the chloroplast increased. At 20 mg·kg^-1DEHP, the nucleolus became integrated, the chromatin of nucleus was agglutinated, and the nuclear membrane was disrupted. Consistent with the ultrastructure results, the contents of chlorophyll a, chlorophyll b and total chlorophyll decreased while the content of hydrogen peroxide（H2O2）increased with increasing concentrations of DEHP, indicating that DEHP stress caused damages to the ultrastructure of cucumber leaves by overproducing reactive oxygen species.

关 键 词：黄瓜 DEHP 亚显微结构 叶绿素 H2O2 

分 类 号：X503.231[环境科学与工程—环境工程]