紫叶杜仲叶色变异研究

Analysis on Leaf Color Variation of Eucommia ulmoides

以6年生紫叶杜仲和对照绿叶杜仲扦插苗为试材,测定了杜仲叶片中花色素苷、叶绿素a、叶绿素b、总叶绿素、可溶性糖等叶色相关物质含量及叶片中苯丙氨酸解氨酶(PAL)活性和pH值在叶色表达期随时间(8-10月)的动态变化,分析了叶色变异与叶片叶绿素、花色素苷、可溶性糖、PAL活性、pH值的相关性,同时对紫色杜仲叶进行遮光处理并探讨光对叶色变异的影响。结果表明:紫叶杜仲叶片内花色素苷含量、PAL活性均高于绿叶杜仲的,而紫叶杜仲叶绿素含量和pH值却低于绿叶杜仲;在8-10月,其叶绿素含量、pH值呈下降趋势,花色素苷含量、可溶性糖含量、PAL活性表现出升高趋势;通过紫叶与绿叶杜仲的对比可以看出,紫叶杜仲叶片变异的主要原因是其花色素苷含量和M值显著高于绿叶杜仲;影响花色素苷和叶绿素含量的主要因子有PAL活性、温度、pH值、光照等。

Determinations were made on anthocyanin,chlorophyll,soluble sugar,phenylalanine ammonialyase（PAL） activity and dynamic pH（August to October,） in leaves of 6-year Eucommia ulmoides cuttings of green and purple leaf.Meanwhile,experiments were conducted on shading purple-color Eucommiae cuttings.The results showed that purple-leaf Eucommia had more content of anthocyanin and PAL activity but lower content of chlorophyll and pH value than green-leaf one.During August and October,purple-leaf Eucommia had a trend of increase of anthocyanin content,soluble sugar PAL activity,while decrease of chlorophyll content and pH value.Comparisons of two colored Eucommia demonstrated that the major effect of color variation was the content of anthocyanin and the ratio of anthocyanin/chlorophyll.Factors to influence content of anthocyanin and chlorophyll were PAL activity,temperature,pH value and light,but had low relation with soluble sugar and content of anthocyanin.