Hokkaido Research Center, Forestry and Forest Products Research Institute (FFPRI), Forest Research and Management Organization, 7 Hitsujigaoka, Sapporo, Hokkaido, 062-8516, Japan; Research Faculty of Agriculture, Hokkaido University, Kita 9 Nishi 9, Sapporo, Hokkaido, 060-8589, Japan.
Hokkaido Research Center, Forestry and Forest Products Research Institute (FFPRI), Forest Research and Management Organization, 7 Hitsujigaoka, Sapporo, Hokkaido, 062-8516, Japan.
Environ Pollut. 2019 Jan;244:332-341. doi: 10.1016/j.envpol.2018.10.007. Epub 2018 Oct 8.
Rare earth elements (REEs) have recently received particular attention due to their accumulation in the environment. Such heightened recognition prompted our evaluation of the possible occurrence of La-induced plant hormesis in the peer-reviewed literature. This study revealed 703 La-induced hormetic concentration/dose responses in plants, which were quantitatively and qualitatively assessed. The maximum (MAX) biological response to low La concentrations/doses is commonly below 150% of control response, with a geometric mean of 142% at 56 μM (geometric mean). The geometric mean concentration of the no-observed-adverse-effect-level (NOAEL) was 249 μM. The MAX:NOAEL distance was commonly below 5-fold, with a geometric mean of 4.5-fold. Hormetic concentration/dose responses varied as per the growth substrate pH, number of concentrations/doses below the NOAEL, and time window. These results provide a unique insight into the effects of low doses of La on plant growth, as well as offer means for improving experimental designs to assess low dose effects.
稀土元素（REEs）由于在环境中积累而受到特别关注。这种认识的提高促使我们在同行评议文献中评估镧诱导植物激素的可能发生。本研究揭示了 703 种镧诱导的植物激素浓度/剂量反应，对其进行了定量和定性评估。对低浓度/剂量镧的最大（MAX）生物反应通常低于对照反应的 150%，在 56 μM（几何平均值）时为 142%。无明显不良效应水平（NOAEL）的几何平均浓度为 249 μM。MAX:NOAEL 距离通常低于 5 倍，几何平均值为 4.5 倍。激素浓度/剂量反应随生长基质 pH、低于 NOAEL 的浓度/剂量数以及时间窗口而变化。这些结果为低剂量镧对植物生长的影响提供了独特的见解，并为改进评估低剂量效应的实验设计提供了手段。
