镧在小麦幼苗富集与幼苗营养生长的关系

通过暴露和暴露恢复试验研究低浓度稀土元素镧对小麦幼苗营养生长的影响.结果表明,幼苗暴露于0.5～25mg/L镧溶液,镧抑制幼苗根的伸长,降低茎叶和根系的干重,降低矿质元素Ca、Mg、Zn、Mn的含量;镧的植物富集速度及镧从根系向茎叶迁移速度与镧暴露浓度呈明显的对数关系.去除镧后,幼苗生长加快,生物量及根长增加,矿质元素含量升高,但已富集的镧主要在作物体内再分配,很难排出体外,且随作物的生长而逐步的稀释,但仍影响作物生长.幼苗中镧的富集量与幼苗相对干重呈负线性相关,幼苗根系生长比茎叶更容易受到溶液中镧抑制.

The relationship between accumulation of lanthanum on wheat seedlings and the seedlings growth

The effects of low concentrations rare earth element La on the growth of wheat seedlings were studied through exposure and exposure-recovery experiments. The results showed that: when the seedlings exposed to La solution of 0.5~2.5mg/L, La inhibited the growth of roots and decreased dry weights of roots and shoots and the contents of mineral elements Ca, Mg, Zn and Mn. The accumulation rates of La and its translocation rates from roots to shoots were positively correlated with its exposure concentration. After La was removed, the seedlings grew more quickly with more biomass and longer roots, and the contents of mineral elements increased. La was mainly redistributed in the whole plant with very little excretion and gradually diluted during the plant growth, but still affected the growth. Contents of La in seedlings had linear correlation with the relative dry weights of seedlings by regression; and the growth of roots was more easily inhabited by La in solution than shoots.