Photoprotective roles of anthocyanins in Begonia semperflorens
Photoprotective roles of anthocyanins in Begonia semperflorens
复制标题
DOI：
10.1016/j.plantsci.2010.05.006
复制
发表时间：
2010-09
期刊：
影响因子：
5.2
通讯作者：
K. Zhang;H. Yu;K. Shi;Yanhong Zhou;Jingquan Yu;X. Xia
中科院分区：
文献类型：
--
作者：
K. Zhang;H. Yu;K. Shi;Yanhong Zhou;Jingquan Yu;X. Xia
花青素被认为在压力条件下提供光保护。以两种不同色素沉着的四花秋海棠为材料，研究了花色苷对其耐高光胁迫能力的影响。在强光胁迫期间和强光胁迫后，红叶的最大光量子效率(Fv/Fm)显著高于绿叶。强光还诱导了两个品种花色苷含量的显著增加。红叶和绿叶在花青素含量、叶绿素含量和Chla/b比值上虽有较大差异，但差异不显著。强光胁迫后，红叶的叶黄素库大小和酶的抗氧化活性均低于绿叶。然而，DPPH法测定的非酶类抗氧化活性，红叶显著高于绿叶。同时，DPPH活性的变化与强光胁迫过程中和胁迫后花色苷含量的变化密切相关。绿光下绿叶的Fv/Fm下降幅度显着大于红叶，但红光和蓝光下绿叶和红叶的Fv/Fm下降幅度相当。不同颜色光下ROS的变化与Fv/Fm的变化相似。我们的结果表明，在强光胁迫下，花青素主要作为滤光器发挥作用，而不是作为抗氧化分子。
Anthocyanins are thought to provide photoprotection under stressful conditions. We used two genotypes of Begonia semperflorens with different pigmentation to study the effects of anthocyanins on tolerance of high-light stress. The maximum quantum yield of PSII (Fv/Fm) in red leaves was significantly higher than that in green leaves during and after high-light stress. High light also induced significant increases in anthocyanins in both genotypes. Despite large differences in anthocyanin content, chlorophyll content and Chl a/b ratio did not differ between red and green leaves. After high-light stress, xanthophyll pool size and enzymatic antioxidant activity were lower in red leaves than in green leaves. Non-enzymatic antioxidant activity measured by DPPH assay, however, was significantly higher in red leaves than in green leaves. Meanwhile, changes in DPPH activity were closely correlated with changes in anthocyanin content during and after high-light stress. Declines in Fv/Fm were significantly greater for green leaves than for red leaves under green light but were comparable between green and red leaves under red and blue light. Changes in ROS under different colors of light were similar to the changes in Fv/Fm. Our results suggest that anthocyanins primarily function as light filters rather than as antioxidant molecules during high-light stress in B. semperflorens.