通过盆栽实验,在适宜水分、中度干旱和严重干旱水分条件下,分别测定了3个不同抗旱类型的7个小麦品种叶片的电阻和电抗以及保护酶活性、MDA含量、细胞膜相对透性、脯氨酸和含水量等生理参数,并拟合了胞外电阻、胞内电阻、驰豫时间以及驰豫时间的分布系数等电阻抗图谱参数,分析了叶片的电阻抗图谱参数与生理参数之间的相关性。结果表明,在受到水分胁迫后,小麦叶片的CAT、POD活性较适宜水分条件下降低,MDA含量、细胞膜相对透性和脯氨酸含量增加,含水量减小;胞外电阻、胞内电阻、驰豫时间以及驰豫时间的分布系数在品种间差异均极显著(P〈0.01),而仅胞内电阻在水分处理间差异显著(P〈0.05);在适宜水分条件下,胞外电阻与细胞膜透性有显著负相关,驰豫时间与丙二醛、含水量之间有显著正相关,而在严重干旱条件下,驰豫时间分布系数与丙二醛含量之间有显著正相关,胞内电阻与含水量之间有显著负相关。可见,胞内电阻和驰豫时间分布系数在一定程度上反映了小麦叶片受水分胁迫的程度。
Electrical resistance and reactance of wheat leaves were researched,which are attributed seven varieties such as dryland,irrigated area and dry-fertilizer. The wheat were growed in pots experienced three water conditions:optimization moisture,moderate drought and severe drought. Extracellular resistance,intracellular resistance,relaxation time and the distribution coefficient of the relaxation time were estimated. CAT,POD,MDA,REL,proline and moisture content of different varieties were determined in three treatments. The correlation between electrical impedance parameters and physiological parameter were analyzed. The results showed that CAT, POD and moisture content were lower than optimization moisture. MDA, membrane permeability and proline are increased. In optimization moisture condition, there are significant negative correlation between extracellular resistance and REL and there are significant positive correlation between relaxation time and MDA, moisture content. In severe drought condition, there are significant positive correlation between the distribution coefficient of the relaxation time and MDA and there are significant negative correlation between intracellular resistance and moisture content. Therefore, water stress degree of wheat can be reflected to a certain extent by distribution coefficient of the relaxation time and intracellular resistance.