落羽杉秋冬季叶色变化的生理生态研究

Ecological physiology of Taxodium distichum leaves color changes in autumn and winter

为探讨落羽杉Taxodium distichum秋冬季叶色变化规律,研究落羽杉在不同光照、温度和不同生境条件下叶色转变时的生态生理变化,以落羽杉成龄植株为材料,于2012年8月下旬至11月中旬用分光光度计测定其不同方位与不同生境条件下叶片叶绿素总质量分数、花色素苷相对含量和可溶性糖质量分数。结果表明:秋冬转色期落羽杉叶片叶绿素总质量分数呈下降趋势,树冠背阴面叶片叶绿素总质量分数明显高于向阳面,向阳东面高于向阳西面;花色素苷相对含量呈上升趋势,11月5日之后显著升高;可溶性糖质量分数呈上升趋势;日平均气温与花色素苷相对含量、可溶性糖质量分数间呈负相关;水生落羽杉叶绿素总质量分数、花色素苷相对含量、可溶性糖质量分数均高于陆生落羽杉,水生落羽杉红叶观赏期较陆生落羽杉长,它们的花色素苷相对含量与叶绿素总质量分数呈显著负相关(P<0.05)。光照充足条件下,生长在水中的落羽杉红叶期要长于陆生的,且有较好的整体观赏性。

To explore the rule of cypress leaf color changes in autumn and winter, and study the physiological characteristics under different illumination, temperature and habitat conditions, the mature cypress trees＇ （Taxodium distichum） variations of chlorophyll, anthocyanin and soluble sugar content in its leaves were measured during the color-changing period from late August to early November by spectrophotometry. The results indicated that the chlorophyll content descended gradually. The chlorophyll content in the leaves in the shady side was significantly higher than that in the sunny side, and that in the east of the sunny side was significantly higher than the west. The anthocyanin content kept ascending slowly before November 5th and increased significantly since then. The soluble sugar content increased gradually. During the experiment, there was a negative correlation between daily average temperature and anthocyanin content, or soluble sugar content. Chlorophyll, anthocyanin and soluble sugar contents of cypress which grown in the water were less than those grown in the field. The red-leaf period of cypress trees which were grown in the water was longer than those grown in the field, and there was a significantly negative correlation （P〈0.05）between anthocyanin and chlorophyll content. Under the adequate sunlight, red-leaf period of cypress trees grown in the water was longer than those grown in the field, and the former had higher ornamental values.