香根草对土壤中几种重金属离子富集能力的比较研究

用组织培养的香根草无菌苗作为试验材料,进行香根草对Cd、Cr、Pb和Ni四种重金属离子的富集能力比较试验,分别测定了香根草体内的重金属含量、香根草与重金属元素的相关性、香根草对重金属的富集系数和根系滞留率.结果表明：香根草对四种重金属离子都具有较高的富集能力.其中,香根草植物体中元素总含量表现为Ni＞Cr＞Pb＞Cd,在茎叶和根中的分含量,均表现为根＞茎叶;香根草与重金属元素的关系中,Cd的相关性最显著;富集系数与重金属浓度呈负相关,以Ni最为明显;从滞留率的角度来看,以Cr在香根草根系的滞留率最大,但对同一种重金属来说,随浓度的变化,香根草根系对它的滞留率却几乎是恒定的.

Comparison of the accumulation ability of Vetiveria zizanioides to several heavy metals in soil

To explore the accumulation ability of V.ziza-nioides to Cd,Ct,Pb and Ni,the aseptic seedling of V.zizanioides from tissue culture were used as experiment materials.The metal contents,relativity between metal and V.zizanioides,accumulation of metal in V.zizanioides,and the detained percentage_of metal in root were measured respectively.The results showed that V.ziza-nioides has high accumulation ability to all of the four heavy metals;The metal element contents of V.zizanioides in sequence were Ni>Cr>Pb>Cd.The divided contents sequence between leaf-stem were root were root>leaf-stem.The significant relativity in Cd contents of V.zizanioides was found.There was a negative correlation between accumulation coefficient and concentration of metal,and it was the most evident to Ni.The detained percentage of Cr in root was considered as the highest.but to the same metal,with the change of its concentration,the detained percentage is nearly permanent to V.zizanioides.