Volatile-Mediated within-Plant Signaling in Hybrid Aspen: Required for Systemic Responses
Volatile-Mediated within-Plant Signaling in Hybrid Aspen: Required for Systemic Responses
复制标题
DOI：
10.1007/s10886-017-0826-z
复制
发表时间：
2017-04-01
影响因子：
2.3
通讯作者：
Blande, James D.
中科院分区：
文献类型：
--
作者：
Li, Tao;Blande, James D.
植物挥发物在植物与其相关社区成员之间的信号传导中起着至关重要的作用，但它们在植物内信号传导中的作用在很大程度上尚未探索，特别是在田间条件下。使用一个系统，包括混合白杨（白杨x tremuloides）和专门的食草性叶甲虫（Phratora laticollis），结合现场，温室和实验室实验，我们研究了是否局部损伤引发系统性反应，在未受损的分支，缺乏血管连接到受损的分支，在何种程度上这是由空气传播的挥发性信号与内部信号。一项通过树苗的脉管系统追踪染料的实验显示，染料从上到下的树枝没有向下移动，这表明树枝之间缺乏血管连通性。然而，我们发现，在现场和实验室条件下，食草动物喂养的上部分支引起未受损的下部分支的挥发性排放。温室实验操纵受损和未受损的分支之间的空气接触表明，挥发性物质的系统诱导几乎被消除时，空气接触中断。我们的研究结果清楚地表明，草食动物诱导的挥发物克服血管的限制和调解植物内的信号。此外，我们发现，挥发性信号导致诱导不同类别的挥发物在现场和环境控制的条件下，在现场观察到较弱的响应。这种差异不仅反映了挥发性信号的剂量和时间依赖性，但也指出，未来的研究应更多地集中在现场观察，以更好地了解挥发性介导的植物内信号的生态作用。
Plant volatiles play crucial roles in signaling between plants and their associated community members, but their role in within-plant signaling remains largely unexplored, particularly under field conditions. Using a system comprising the hybrid aspen (Populus tremula x tremuloides) and the specialized herbivorous leaf beetle (Phratora laticollis) and, combining field, greenhouse and laboratory experiments, we examined whether local damage triggered systemic responses in undamaged branches that lack vascular connection to the damaged branches, and to what extent this was caused by airborne volatile signals versus internal signals. An experiment tracing dye through the vasculature of saplings revealed no downward movement of the dye from upper to lower branches, suggesting a lack of vascular connectivity among branches. However, we found under both field and laboratory conditions that herbivore feeding on upper branches elicited volatile emissions by undamaged lower branches. Greenhouse experiments manipulating air contact between damaged and undamaged branches showed that systemic induction of volatiles was almost eliminated when air contact was interrupted. Our findings clearly demonstrate that herbivore-induced volatiles overcome vascular constraints and mediate within-plant signaling. Further, we found that volatile signaling led to induction of different classes of volatiles under field and environment controlled conditions, with a weaker response observed in the field. This difference not only reflects the dose- and time-dependent nature of volatile signaling, but also points out that future studies should focus more on field observations to better understand the ecological role of volatile-mediated within-plant signaling.