三种有机磷农药对大麦毒性效应的研究

Toxicity of Three Organophosphorus Pesticides on Hordeum Vulgare Seedling

使用浸种和浸种加喷施两种方法,研究了3种有机磷农药———马拉硫磷、对硫磷和久效磷在不同浓度条件下对大麦幼苗生长发育、根细胞分裂及叶绿素含量的影响。结果表明,3种有机磷农药对大麦种子萌发和根伸长均有一定的抑制作用,抑制程度随浓度增大而加强。幼苗根伸长比种子萌发对有机磷农药胁迫更为敏感。不同浓度的有机磷农药处理后均能抑制根细胞分裂,使有丝分裂指数下降。浸种法和浸种加喷施法都能使大麦叶片叶绿素含量降低,但浸种加喷施法对叶绿素合成的影响明显大于浸种法。3种有机磷农药对大麦幼苗的毒性程度依次为马拉硫磷>对硫磷>久效磷。

Phyto- toxicity of parathion, monocrotophos and malathion at different doses on seedling growth, cell division and chlorophyll content in Hordeum vulgare were studied using seed soaking and seed soaking plus spray medium. The results showed that frequency of seed germination and rate of root growth were found to be affected by three organophosphorus pesticide at doses of 300～ 1 200 mg· L- 1, while growth inhibition effect increased with the increasing concentrations of organophosphorus pesticide. The root growth was more sensitive to the organophosphorus pesticide stress than the seed germination. The mitotic index decreased progressively with increasing organophosphorus pesticide concentration and exposure duration. Seed soaking and seed soaking plus stray medium could reduce the chlorophyll content of Hordeum vulgare seedling , but seed soaking plus spray medium had a stronger toxic effect to the chlorophyll than treated with seed soaking medium. It was suggested that the order of three organophosphrus pesticide on toxic effects be: malathion > parathion > monocrotophes.