镉胁迫下两种不同小白菜的生长、镉吸收及其亚细胞分布特征  

CHARACTERIZATION OF PLANT GROWTH,CADMIUM UPTAKE AND ITS SUBCELLULAR DISTRIBUTION IN PAKCHOI EXPOSED TO CADMIUM STRESS

作　　者：宋阿琳 李萍[1,2] 李兆君 梁永超 

机构地区：[1]中国农科院农业资源与农业区划研究所,农业部作物营养与施肥重点实验室,北京100081 [2]山西农业大学,太谷030801

出　　处：《环境化学》2011年第6期1075-1080,共6页Environmental Chemistry

基　　金：国家“十一五”科技支撑计划项目(2006BAD02A15)资助

摘　　要：通过室内溶液培养试验,研究了镉(0.5 m·gL-1、5.0 m·gL-1)胁迫对两个不同镉耐性小白菜品种上海青(Cd敏感型)和杭油冬(Cd耐性)的生长、Cd吸收及亚细胞分布的影响.结果表明,高Cd胁迫10 d后两个小白菜生长受到严重抑制,植物地上部和地下部Cd含量随着Cd处理浓度的增加而增加,且Cd主要积累在植物的根系.此外,Cd在地上部和地下部亚细胞组分中的分配率不同,在地上部各组分中,Cd主要分布在细胞质,其次是细胞壁,分配率最少的是细胞器.在地下部各组分中,在低浓度处理下Cd在亚细胞组分中的分布与地上部分布一致,但在高Cd处理下Cd主要分布在细胞壁,其次是细胞质,在细胞器中分布最少.Cd在两个不同耐性小白菜品种中的吸收和分布存在显著的基因型差异.A series of hydroponics experiments were performed to study the effect of Cd added 0.5 or 5.0 mg·L-1 Cd on plant growth,Cd uptake and subcellular distribution in two contrasting pakchoi（Brassica chinensis L.） cultivars： i.e.cv.Shanghaiqing,a Cd-sensitive cultivar,and cv.Hangyoudong,a Cd-tolerant cultivar.Shoot and root growth was inhibited significantly in both Cd-sensitive and Cd-tolerant pakchoi plants that were exposed to 5.0 mg·L-1 Cd for ten days.Shoot and root Cd concentrations in the two cultivars used increased with increasing level of Cd supply,and significantly higher Cd concentration was observed in roots than in shoots.Besides,significant differences in Cd subcellular distribution were found between shoots and roots.Of the different parts of shoots,Cd was mainly localized in the cytoplasm,followed by cell walls and organelles at both Cd levels（0.5 and 5 mg·L-1 Cd）.The same was true for plant roots at 0.5 mg·L-1 Cd.However,Cd was mainly localized in the cell walls,followed by cytoplasm and organelles at 5 mg·L-1 Cd.There existed significant genotypical difference in Cd uptake and distribution.

关 键 词：镉 细胞壁 亚细胞分布 小白菜 

分 类 号：X173[环境科学与工程—环境科学]