小麦根系菲与磷吸收及转运的相互作用

摘要

作物根系对多环芳烃(PAHs)与磷吸收及转运之间的相互作用研究对农产品的安全生产和PAHs污染环境植物修复的强化具有重要意义。为此，本文以菲为PAHs的代表，采用水培试验研究了不同磷、菲水平下小麦根系菲、磷吸收及其转运的效果，旨在揭示植物根系吸收PAHs与磷素的相互作用。结果表明，在0~1200μmol•L￣1磷浓度范围内，小麦根系、茎叶菲含量在低磷浓度(10μmol•L￣1)时最高，分别为36.87 mg•kg￣1和2.07 mg•kg￣1；磷含量总体呈现随磷处理浓度的升高而增大的趋势；成对数据t￣检验显示无论加菲与否，根系、茎叶磷含量无显著性差异(P>0.05)。磷可促进菲从根部向地上部转运，而菲对磷转运没有显著性影响。在低磷浓度下(10μmol•L￣1)，随着菲浓度的升高，小麦根系、茎叶菲含量呈现显著升高趋势(P<0.05)。磷、菲共存处理介质pH升高幅度大于单一处理。%It is important to investigate the interactions of polycyclic aromatic hydrocarbons (PAHs) and phosphor￣us during their uptake and translocation in crop roots for the safe production of food crops and the enhancement in phytoremediation of PAH￣contaminated soil and water. In this paper, the hydroponic experiments were employed for the uptake and transfer of phenanthrene and phosphate in wheat roots at different phosphorus and phenanthrene concentrations. Phenanthrene contents in wheat roots and shoots peak with 36.87 mg•kg￣1 and 2.07 mg•kg￣1 respec￣tively at 10 μmol•L￣1 phosphorus. Phosphorus content is raised in both roots and shoots with an increase of phos￣phorus in the range of 0￣1 200 μmol•L￣1 . According to the paired t￣test, there are no significant differences (P>0.05) in phosphorus contents of wheat roots or shoots between the treatments with and without phenanthrene. Phos￣phorus can escalate the translocation of phenanthrene from wheat roots to shoots, but phenanthrene has no signifi￣cant effects on phosphorus acropetal translocation. Nutrient solution pH in the presence of phenanthrene and phos￣phorus increases more than that in the presence of either phenanthrene or phosphorus.