不同黄麻品种对重金属污染农田镉的富集和转移效率研究

Cadmium accumulation and translocation in different jute(Corchorus capsularis L.) cultivars growing in heavy metal contaminated paddy soil

为研究黄麻(Corchorus capsularis L.)植株对重金属污染农田中Cd的富集和转移效率,以湖南省株洲县为试验区,研究3个黄麻品种6个植株器官的干物质积累、Cd富集和转移特征。结果表明:木质部和韧皮部是黄麻植株干物质积累的主要器官;不同品种的黄麻及其器官间的Cd含量均呈显著差异,3个品种中连红黄麻各器官的Cd含量均高于闽侯红皮和黄麻179。6个植株器官中,蒴果和叶柄的Cd含量显著高于其他器官,平均值分别为4.75 mg·kg^-1和4.27 mg·kg^-1,其他器官Cd含量均值从高到低依次为叶片>根部>木质部>韧皮部;地上部器官间Cd转移效率研究表明,3个品种地上部的Cd转移系数均在1以上。Cd从木质部和韧皮部到叶柄和蒴果的转移能力较强,从根部到木质部和韧皮部、从叶柄到叶片的转移能力较弱。对黄麻Cd总富集量评估表明,连红黄麻的总富集量最高,每公顷可富集53.3 g的Cd,木质部占总富集量的33.11%~42.99%。研究表明,黄麻对中度Cd污染农田中的Cd有较高的富集和转移能力,可作为植物修复材料加以利用。

To investigate the Cd phytoextraction capacity of jute(Corchorus capsularis L.)planted in heavy metal contaminated paddy soil,a field experiment was conducted in a medium cadmium-contaminated paddy field in Zhuzhou County,Hunan Province,China.Biomass and Cd concentration of six plant organs in three jute cultivars were investigated and total Cd uptake was evaluated.The results showed most biomass was stored in the xylem and phloem.Cd concentration was significantly different among cultivars and among organs.Cd accumulated more in‘Lianhonghuangma’than in the other two jute cultivars.Capsule(4.75 mg·kg^-1)and petiole(4.27 mg·kg^-1)showed significantly higher Cd concentrations than the other four organs,which followed in the order of leaf>root>xylem>phloem.Transportation factor of the aerial part exceeded one in all the three cultivars.The ability of Cd transportation from the xylem/phloem to the capsule/petiole was higher than that from the root to the xylem/phloem and from the petiole to the leaf.Total Cd accumulation in‘Lianhonghuangma’was 53.3 g·hm^-2,higher than that in‘Minhouhongpi’and‘Huangma 179’.Xylem was the main Cd accumulation organ which extracted 33.11%~42.99%of the total Cd absorbed by the plant.Our research indicated jute could be used as an accumulator for phytoremediation of Cd-contaminated soil in southern China.