镧对低温胁迫萝卜幼苗保护酶系统的影响

[目的]研究低温冷害对萝卜幼苗活性氧代谢保护酶系统的影响及稀土镧对植物抗冷性的诱导。[方法]以白沙短叶13-6早萝卜的幼苗为试料,采用模拟低温冷害的实验法,通过测定抗氧化保护酶系统中的SODP、OD、CAT以及常用的MDA含量变化,研究镧对低温胁迫萝卜幼苗的缓解作用。[结果]以相对电导率为指标筛选出LaCl3最佳浓度为10 mg/L。在10和5℃低温条件下,MDA含量明显上升,SOD先上升再下降。POD、CAT活性随胁迫温度的降低,也呈先升后降趋势。在低温胁迫过程中,加入稀土镧处理后发现,SOD、POD、CAT酶活性呈现下降趋势,MDA含量明显下降。[结论]适当浓度的稀土镧处理能诱导萝卜幼苗对低温胁迫产生抗性,减轻低温对萝卜幼苗的伤害。

Effects of Lanthanum on the Protective Enzyme in Radish Seedlings under Low Temperature Stress

[Objective] The research aimed to study the effects of low temperature damage on the activated oxygen metabolism protective enzyme system and the induction of plant cold-tolerance by rare earth lanthanum(La).[Method] With the seedlings of early radish variety Baisgaduanye 13-6 as tested materials,based on determining the content changes of SOD,POD,CAT and common MDA in antioxidation protective enzyme system by the test method of simulated low temperature damage,the alleviating effect of La on radish seedlings were studied under low temperature stress.[Result] With the relative conductivity as index,LaCl3 was screened out,with the optimum concn.of 10 mg/L.Under the low temperature(10 and 5 ℃),MDA content obviously increased,and SOD content first increased and then decreased.With the decrease of stress temperature,the activities of POD and CAT also showed the trend of first increasing and then decreasing.In the process of low temperature stress,it was found that the enzyme activities of SOD,POD and CAT showed the decreasing trend and MDA content was obviously decreased after treatment of adding rare earth La.[Conclusion] Treatments with suitable concn.of rare earth La could induce the radish seedlings to produce resistance to low temperature stress and alleviate the damage of low temperature to radish seedlings.