Cr6+胁迫下小麦幼苗地上部分生长及DNA损伤效应的研究

目的]阐明Cr6+影响小麦幼苗生长发育的毒理机制。方法]研究5~100 mg/LCr6+胁迫72 h对3 d和10 d龄小麦幼苗地上部分生长的影响及DNA损伤效应。结果]5~100 mg/LCr6+均表现出降低两苗龄幼苗苗高、地上部分鲜重、干重的效应;3 d龄幼苗比10 d龄幼苗对Cr6+胁迫更敏感;Cr6+导致小麦幼苗叶片DNA含量显著降低,3 d龄幼苗叶片DNA含量下降的幅度大于10 d龄幼苗;5~100mg/LCr6+均引起3 d和10 d龄幼苗地上部分DNA的增色效应值高于对照值。结论]Cr6+造成的DNA损伤可能是影响不同龄期小麦幼苗生长的主要原因之一。

Research on Aerial Part Growth and DNA Damage of Wheat Seedlings under Cr6+ Stress

Objective] The aim was to clarify the toxicological mechanism of Cr6+ influencing the growth and development of wheat seedling.Method] The influence of Cr6+ stress at 5～100 mg/L for 72 h on aerial part and the DNA damage of 3-day-old and 10-day-old wheat seedlings were studied.Result] 5～100 mg/L Cr6 showed the effects of decreasing seedling height,fresh weight and dry weight of aerial part of two seedling-age seedlings.The 3-day-old seedlings were more sensitive to Cr6+ stress than 10-day-old seedlings.Cr6+ decreased the DNA content in wheat seedling leaves significantly and the declining extent of DNA content in the leaves of 3-day-old seedlings was bigger than that in the leaves of 10-day-old seedlings.5～100 mg/L Cr6+ all induced that the DNA hyperchromic effect value of aerial part of 3-day-old and 10-day-old seedlings were higher than that of CK.Conclusion] The DNA damage made by Cr6+ may be one of main reasons influencing seedling growth of wheat seedlings with different ages.