锗在土壤-水稻系统内的迁移和积累规律

Law of Translocation and Accumulation of Germanium in Soil-rice Plant System

以吉农大3号水稻和稻田水稻土为材料,锗胁迫水平分别为0.0、5.0、10.0、20.0、40.0μg·g-1,进行温室盆栽模拟试验,研究了锗在土壤-水稻系统内的迁移和积累规律。结果表明,不同锗处理水平下,植株各干重组织中锗含量变化规律一致,茎叶>根>糙米;随着土壤中锗含量的增加,糙米中锗含量增加非常明显,土壤中锗含量为40.0μg·g-1时糙米中锗的平均含量高达17.8μg·g-1干重。在20.0μg·g-1处理水平下,水稻在整个生长期内不断吸收锗,但同一部位锗的含量在灌浆期最大。拟合曲线表明,以每盆水稻的平均总籽粒重减少10%为标准时,土壤锗污染的阈值为34.3μg·g-1。试验结果可为锗的环境和生态效应研究提供一定的理论依据。

Translocation and accumulation of germanium in paddy soil-flee plant system in greenhouse were studied using rice cultivar＇Ji- nongda 3＇. The added levels of germanium to paddy soil were 0.0, 5.0, 10.0, 20.0 and 40.0μg·g^-1, respectively. All treatment levels shared the same distribution law of germanium in rice plant body, being straw〉root〉unpolished flee in terms of germanium concentration in dried organs. Ge concentration in rice increased rapidly with the increasing Ge content in soil and Ge concentration in flee plant could reach 17.8 μg·g^-1 at the added level of 40 μg·g^-1. When germanium concentration was 20.0 μg·g^-1 in soil, rice plant absorbed germanium during the whole growth period, but germanium concentrated more in root and straw at plasma stage than at other stages. When the germanium content was 20 μg·g^-1 in soil, necrotic spots appeared on the leaf blades. The fitting curve showed that the averaged grain weight per pot would be decreased by 10% when germanium content was more than 34.3μg·g^-1 in soil. The results can theoretically support the study of environmental and ecologic effect of germanium.