Page 137 - 《广西植物》2025年第6期
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6 期 欧阳子龙等: 池杉和落羽杉转色期叶片衰老过程的生理特征差异 1 1 2 3
Abstract: During the autumn and winter seasonsꎬ both Taxodium ascendens and T. distichum undergo a color transition
period in which their leaves gradually turn orange or redꎬ making them common ornamental trees with colored foliage in
gardens. Analyzing the physiological characteristics of leaf color transition period in these two species is crucial for
understanding the aging and coloring processes of these treesꎬ providing valuable guidance for the application of
ornamental trees with colored leaves in garden landscapes. This study conducted measurements on pigment contentꎬ
antioxidant enzyme activityꎬ osmoregulatory substance contentsꎬ malondialdehyde ( MDA) contentꎬ and chlorophyll
fluorescence parameters in aging leaves of T. ascendens and T. distichum during the color transition period. Statistical
methods such as significant difference analysisꎬ correlation analysisꎬ linear fittingꎬ and membership function analysis
were employed to comprehensively evaluate the physiological state of aging leaves from both species. The results were as
follows: (1) The AC/ CHLa+b ratio in T. ascendens and T. distichum leaves increased rapidly with age reaching 11.46
and 7.13 respectivelyꎻ this directly contributed to the orange ̄red hue observed in their foliage. (2) During aging
processesꎬ superoxide dismutase (SOD) and catalase (CAT) activities and soluble sugar content decreased while MDA
content first increased and then decreasedꎻ however peroxidase ( POD )ꎬ ascorbate peroxidase ( APX )ꎬ and
phenylalanine ammonialyase (PAL) activities increasedꎬ indicating a resistance effect against leaf senescence. (3) The
photochemical conversion efficiency and heat dissipation ability could represent the change of physiological and
biochemical indexes wellꎬ and reflect the aging process. (4) Comprehensive scores showed that at any given time
T. ascendens consistently exhibited lower scores than T. distichum suggesting superior physiological status for T.
ascendens. In conclusionꎬ T. ascendens and T. distichum demonstrate similar physiological characteristics of leaf
senescenceꎬ but T. ascendens enteres into this phase earlier than T. distichum. In landscape applicationsꎬ combining
plantings of T. ascendens alongside T. distichum can extend overall periods for colorful foliage display.
Key words: Taxodium ascendensꎬ Taxodium distichumꎬ autumn leavesꎬ chlorophyll fluorescenceꎬ aging process
叶色是季节景观最直接的构成要素ꎬ随着我 植物叶色变化与衰老过程密不可分ꎬ随着衰
国园林绿化事业进一步发展ꎬ大量色叶树种被广 老进 程 加 剧ꎬ叶 绿 素 含 量 迅 速 降 低 ( Amy et al.ꎬ
泛种植ꎬ城市景观效果和层次更加丰富( 傅文霞ꎬ 2024ꎻ Yang et al.ꎬ 2024)ꎮ 抗氧化系统是抵御衰
2020)ꎮ 随着秋冬季温度逐渐降低ꎬ池杉和落羽杉 老的一道重要防线ꎬHuang 等(2024) 研究认为ꎬ抗
叶片呈现由绿到橙( 红) 的色彩变化ꎬ既是季节景 氧化酶对维持叶绿体稳态具有重要意义ꎮ 植物通
观的展现ꎬ又是转色期叶片衰老的自然过程ꎮ 池 过提高叶片中抗氧化酶的活性及时清除活性氧自
杉和落羽杉作为色叶树种不仅美化了城市风貌ꎬ 由基ꎬ从而减少了色素的降解ꎬ延缓了衰老( Shi et
而且还提高了城市的生命力ꎮ 但是ꎬ过快衰老会 al.ꎬ 2019ꎻ Wen et al.ꎬ 2022)ꎮ 除抗氧化酶外ꎬ色
使叶片凋落进而导致叶色观赏期缩短ꎬ景观效果 素合成酶和营养物质对叶片呈色亦产生了影响ꎮ
不 佳ꎮ 花 色 素 苷 ( anthocyaninꎬ AC )、 叶 绿 素 苯 丙 氨 酸 解 氨 酶 ( phenylalanine ammonialyaseꎬ
(chlorophyllꎬ CHL) 和 类 胡 萝 卜 素 ( carotenoidꎬ PAL)是 AC 合成途径中一种重要的酶ꎬ其活性决
Car)是决定叶色的主要色素ꎬ其中 AC 可使叶片呈 定了植物衰老过程中 AC 含量的变化( Zhan et al.ꎬ
现红色ꎬCHL 和 Car 使叶片分别呈现绿色和黄色 2022)ꎮ 可溶性糖( soluble sugarꎬ SS) 和可溶性蛋
(商彩 丽 等ꎬ 2021ꎻ Yuan et al.ꎬ 2021ꎻ Li et al.ꎬ 白(soluble proteinꎬ SP)可作为合成酶的能量底物、
2022)ꎮ 杨淑红(2012)研究发现ꎬ叶片中色素的种 营养和渗透调节物质ꎬ直接调控植物生理状况( 贾
类和比例是叶色变化的直接原因ꎬ当 AC / CHL 的 湘璐等ꎬ2022)ꎬ提高植物衰老过程中的生理活性
值升高时ꎬ叶片倾向于红色ꎬ反之则倾向于绿色ꎻ (刘朝茂和李成云ꎬ 2017ꎻHan et al.ꎬ 2022)ꎮ 叶片
当 Car 含量较高时ꎬ叶片倾向于黄色ꎮ 前人研究认 衰老过程中丙二醛( malondialdehydeꎬ MDA) 积累
为叶片由绿变红的过程往往伴随着色素含量的剧 (Kun et al.ꎬ 2022ꎻ He et al.ꎬ 2024)ꎬ过高的 MDA
烈变化ꎬ如美国红枫(高焕章等ꎬ2013)、鸡爪槭( 蔡 含量又进一步损伤组织ꎬ加速衰老ꎬ使叶色发生改
雪雁等ꎬ2015)和纳塔栎(许晓波ꎬ2015)等ꎮ 变ꎮ 吕志伟等(2022)通过对玉米穗位叶的衰老过

