不同锌处理下重金属超量积累植物Thlaspi caerulescens对养分的吸收

Uptake of mineral elements by hyperaccumulator Thlaspi caerulescens under different zinc treatments

通过３个不同的实验研究了不同锌处理（１～５０００μｍｏｌ／Ｌ）下重金属超量积累植物Ｔｈｌａｓｐｉｃａｅｒｕｌｅｓｃｅｎｓ对铁、钙、镁、钾、锰和硫吸收的影响。结果显示，在供应Ｆｅ－ＥＤＴＡ的条件下，增加处理的锌浓度显著减少Ｔ．ｃａｅｒｕｌｅｓｃｅｎｓ地上部的全铁含量；当使用Ｆｅ－ＥＤＤＨＡ时，锌处理对地上部铁含量的影响不显著，而根系中全铁和可溶性铁含量随溶液中锌浓度的增加而增加；停止供锌，明显降低根系全铁含量。锌浓度＜１０００μｍｏｌ／Ｌ的处理对Ｔ．ｃａｅｒｕｌｅｓｃｅｎｓ地上部的钾、钙和镁含量没有影响。无论在供应Ｆｅ－ＥＤＴＡ还是Ｆｅ－ＥＤＤＨＡ的条件下，植株地上部和根系硫含量在所有锌处理之间均没有显著差异。

Three solution cultures were conducted to investigate the effect of zinc treatment (1~5 000 μmol/L) on the concentrations of Fe, Ca, Mg, K, Mn and S in the tissues of hyperaccumulator Thlaspi caerulescens . Zinc treatment decreased significantly the concentrations of total Fe in the shoots under Fe(Ⅲ)EDTA supply condition. When a specific Fe(Ⅲ) chelator, EDDHA, was used in the experiment 2, Zn treatment had no sigificant effect on the shoot Fe concentrations. But in the roots, the concentrations of total and soluble Fe increased with increasing Zn in solution. Withholding Zn supply decreased the root Fe concentration. Zinc treatment with less than 1 000 μmol/L had no significant effect on the concentrations of , Ca and Mg in the shoots. No significant differences in the shoot S concentrations were also found among all Zn treatments.