铬胁迫对莴苣幼苗生长的影响

采用砂培法,研究了莴苣幼苗在生长过程中受到不同质量浓度Cr3+胁迫后,植株的叶绿素合成、可溶性糖与脯氨酸含量以及膜脂过氧化程度和抗氧化酶活性等方面的变化情况。结果表明:Cr3+≤40 mg/L时对莴苣叶绿素合成有一定促进作用,在40 mg/L时叶绿素含量最大,约为对照的145%;Cr3+≤80 mg/L能诱导并提高SOD、POD活性,在Cr3+为80 mg/L时,活性达到最大值,分别是对照的253%、287%;植株受到Cr3+(≤80 mg/L)胁迫,其体内可溶性糖含量也呈现增加趋势,在80 mg/L时为对照的207%,而高质量浓度的Cr3+(>80 mg/L)不但抑制酶的活性,而且植株体内可溶性糖含量也呈下降趋势,例如,当Cr3+为320 mg/L时,SOD、POD和可溶性糖含量分别为对照的27%、31%和24%;脯氨酸和MDA则随着质量浓度的升高而呈现增加趋势。

Effect of Cr3+ Stress on the Growth Characteristics of Lettuce Seedlings

In this article,the indoor sandculture under the condition of different Cr3+ concentrations was used to study the change of the chlorophyll synthesis,the contents of proline and soluble sugar,oxidative damage degree and the activity of antioxidant enzyme,etc.The results indicated that Cr3+stress(≤40mg/L) had some stimulativing effect on chlorophyll synthesis,the contents of chlorophyll was the highest up to about 145% of the control at the concentration of 40 mg/L;Cr3+stress(≤80mg/L) could induce and improve the activity of SOD and POD,which reached a maximum,respectively 253% and 287% of the control;the content of soluble sugar in plant body presented increasing trend at Cr3+concentration≤80mg/L and was 207% of the control at the concentration of 80mg/L;under higher Cr3+ concentration(>80mg/L),the enzyme activity were inhibited,soluble sugar content was also declined,the enzyme activit of SOD,POD and the content of soluble sugar respectively were 27%,31% and 24% of the control at Cr3+ concentration of 320mg/L;the contents of proline and MDA increased with increasing of Cr3+ concentration.