外源褪黑素对镉胁迫下小麦幼苗生长的影响

Effects of exogenous melatonin on the growth of wheat seedlings under cadmium stress

为探究外源褪黑素(MT)对镉(Cd)胁迫下小麦幼苗生长的影响,本试验以涡麦99品种小麦为研究对象,采用室内温箱水培的方法,首先对其进行100μmol/L浓度的Cd胁迫,然后叶面喷施不同浓度(0、10、100和1000μmol/L)的MT,测定处理后小麦的株高、鲜重、干重、叶绿素、SOD活性、POD活性以及MDA含量。结果显示,在Cd胁迫下,与空白对照相比,喷施不同浓度MT后,小麦的株高、鲜重、干重和叶绿素含量及POD和SOD活性提高,小麦MDA含量降低。综上,在Cd胁迫下,喷施MT可促进小麦的生长,增强幼苗的抗逆性,其中喷施100μmol/L的MT对小麦的株高、鲜重、干重、叶绿素含量及SOD活性的促进效果较佳,1000μmol/L的MT对提高POD活性和降低MDA含量效果较好。

To explore the effect of exogenous melatonin(MT)on the growth of wheat seedlings under cadmium(Cd)stress,this experiment took wheat of Womai 99 as the research object,and adopted the method of indoor temperature tank hydroponics to stress wheat with 100μmol/L concentration of Cd.Leaf surface was sprayed with different concentrations of MT(0,10,100 and 1000μmol/L),and the plant height,fresh weight,dry weight,chlorophyll,SOD activity,POD activity and MDA content of wheat were measured respectivly.The results showed that under Cd stress,the plant height,fresh weight,dry weight,chlorophyll content,POD and SOD activities of wheat were increased,and the MDA content of wheat was decreased after different concentrations of MT were sprayed compared with blank control.In conclusion,under Cd stress,MT spraying could promote wheat growth and enhance the stress resistance of wheat seedlings,and 100μmol/L MT had better effects on plant height,fresh weight,dry weight,chlorophyll content and SOD activity,and 1000μmol/L MT had better effects on increasing POD activity and decreasing MDA content.