摘 要：以周麦18为材料，采用室内土培法研究了不同处理时间下铅镉胁迫、增强UV-B辐射胁迫及复合胁迫对小麦幼苗叶片中叶绿素、丙二醛、游离脯氨酸、可溶性糖、可溶性蛋白含量及过氧化物酶活性的影响。结果表明，小麦幼苗叶片中的叶绿素含量在3种胁迫处理下均比对照组降低，在复合胁迫下叶绿素含量下降最明显；MDA和游离脯氨酸含量在3种胁迫处理下比对照组明显增加，而且增加量与处理时间呈正相关，复合胁迫下MDA和游离脯氨酸含量增加最多；可溶性糖含量在3种胁迫处理下均与对照无明显差异；可溶性蛋白含量在3种胁迫处理下均呈现倒“U”型变化；POD活性在增强UV-B辐射胁迫下呈减弱趋势，在铅镉胁迫下呈增强趋势，在复合胁迫下呈先增强后减弱趋势。上述结果说明了小麦幼苗叶片中的多种生理生化指标在3种胁迫处理下均会受到不同程度的影响。
关键词：小麦；UV-B辐射；Pb+Cd胁迫；复合胁迫；生理指标
Effects of Enhanced UV-B Radiation and Pb, Cd Stress on Physiological and Biochemical Characteristics of Wheat
Abstract: Using ordinary wheat named zhoumai 18 as materials, the effects of enhanced UV-B radiation stress, Pb+Cd stress and compound stress under different processing time on content of chlorophyll, MDA, free proline, soluble sugar, soluble protein and peroxidase activity of wheat seedling leaves were researched in pot experiment. The results showed that the total chlorophyll content of wheat seedling leaves was reduced under three kinds of stress treatments compared with the control group, the total chlorophyll content under compound stress showed the most obvious reduction; The content of MDA and free proline was higher under three kinds of stress treatments than the control group, furthermore, the increment was positive correlated with processing time, MDA content and free proline content showed the most obvious increase under compound stress; There was no significant difference in soluble sugar content between three kinds of treatment groups and the control group; Soluble protein content under three kinds of treatment groups all showed inverted "U" shape change; Peroxidase activity showed gradual reduction trend under enhanced UV-B radiation stress and gradual increase trend under Pb+Cd stress instead, furthermore, peroxidase activity under compound stress treatment became increased and then decreased gradually with the increasing processing time. The above statement showed that lots of physiological indexes of wheat seedling leaves were subject to the impact of varying degrees under three kinds of stress treatments.
Key words: Wheat; UV-B radiation; Pb+Cd stress; Compound stress; Physiological indexes
目录
摘 要 1
引言 1
1. 材料与方法 2
1.1 实验材料 2
1.2 方法 2
1.2.1 小麦幼苗培养 3
1.2.2 铅、镉胁迫液的配制 3
1.2.3 铅、镉胁迫处理 3
1.2.4 增强UV-B辐射胁迫处理 3
1.2.5 增强UV-B辐射胁迫和铅、镉胁迫复合处理 3
1.2.6 各种生理指标的测定 4
2. 结果与分析 4
2.1 各种处理下小麦幼苗叶片中叶绿素含量的变化 4
2.2 各种处理下小麦幼苗叶片中丙二醛（MDA）含量的变化 5
2.3 各种处理下小麦幼苗叶片中游离脯氨酸含量的变化 6
2.4 各种处理下小麦幼苗叶片中可溶性蛋白含量的变化 7
2.5 各种处理下小麦幼苗叶片中可溶性糖含量的变化 8
2.6 各种处理下小麦幼苗叶片中过氧化物酶活性的变化 9 增强UV-B辐射和Pb、Cd胁迫对小麦生理生化特性的影:http://www.751com.cn/shengwu/lunwen_25.html