干旱对小麦幼苗Cu、Mn含量的影响及其机理研究

Effect of drought on content of copper and manganese in wheat seedlings and related mechanism

采用液体培养法,研究了不同干旱处理方法,即每天间断干旱1 h2、h、3 h、4 h和连续干旱24 h,对小麦幼苗两种微量元素Cu、Mn的吸收、分布及叶绿素含量的影响。结果表明:间断干旱1 h、2 h处理,小麦幼苗根、茎、叶的Cu、Mn含量及叶绿素含量均有所增加,间断干旱2 h处理增加更显著;间断干旱3 h4、h和连续干旱处理均使小麦幼苗根茎叶中Cu、Mn含量及叶绿素含量降低,连续干旱处理降低最显著。随着干旱程度的增加,小麦幼苗Cu、Mn含量呈"钟型曲线"变化,即先随干旱程度增加而增加,当干旱达到一定程度后随干旱程度增加而减少。小麦幼苗Cu、Mn含量和叶绿素含量变化趋势一致,三者高度相关。说明适度的干旱处理可增加小麦幼苗中Cu、Mn两种微量元素的含量,而过度干旱则导致小麦幼苗中Cu、Mn含量降低。

Two kinds of drought treatments： discontinuous drought treatment（1 h, 2 h, 3 h, 4 h each day） and 24 h continuous drought treatment were adopted to wheat seedlings. Copper and manganese content in different parts of seedlings and chlorophyll content were detected to investigate the effect of different drought treatments. The results indicated that the content of copper, manganese and chlorophyll all increased in wheat seedlings under discontinuous drought treatment of 1 h and 2 h, while the treatment of 2 h was more effective. The discontinuous drought treatment of 3 h, 4 h and continuous drought treatment led to decrease of the content of copper, manganese and chlorophyll, with seedlings of continuous drought treatment decreasing observably. The experiment demonstrated that mild drought treatment could increase the content of copper and manganese in wheat seedlings, while severe drought treatment decreased them.