Helmholtz Zentrum München, Institute of Biochemical Plant Pathology, Research Unit Environmental Simulation, Neuherberg, Germany.
Helmholtz Zentrum München, Institute of Biochemical Plant Pathology, Neuherberg, Germany.
Plant Cell Environ. 2021 Apr;44(4):1151-1164. doi: 10.1111/pce.14010. Epub 2021 Feb 18.
Isoprene and other terpenoids are important biogenic volatile organic compounds in terms of atmospheric chemistry. Isoprene can aid plant performance under abiotic stresses, but the fundamental biological reasons for the high emissions are not completely understood. Here, we provide evidence of a previously unrecognized ecological function for isoprene and for the sesquiterpene, ß-caryophyllene. We show that isoprene and ß-caryophyllene act as core components of plant signalling networks, inducing resistance against microbial pathogens in neighbouring plants. We challenged Arabidopsis thaliana with Pseudomonas syringae, after exposure to pure volatile terpenoids or to volatile emissions of transformed poplar or Arabidopsis plants. The data suggest that isoprene induces a defence response in receiver plants that is similar to that elicited by monoterpenes and depended on salicylic acid (SA) signalling. In contrast, the sesquiterpene, ß-caryophyllene, induced resistance via jasmonic acid (JA)-signalling. The experiments in an open environment show that natural biological emissions are enough to induce resistance in neighbouring Arabidopsis. Our results show that both isoprene and ß-caryophyllene function as allelochemical components in complex plant signalling networks. Knowledge of this system may be used to boost plant immunity against microbial pathogens in various crop management schemes.
异戊二烯和其他萜类化合物是大气化学中重要的生源挥发性有机化合物。异戊二烯可以帮助植物在非生物胁迫下发挥性能，但高排放的基本生物学原因尚不完全清楚。在这里，我们提供了异戊二烯和倍半萜，β-石竹烯先前未被认识到的生态功能的证据。我们表明，异戊二烯和β-石竹烯作为植物信号网络的核心成分，诱导邻近植物对微生物病原体的抗性。我们用丁香假单胞菌挑战拟南芥，在接触纯挥发性萜类化合物或转化后的杨树或拟南芥植物的挥发性排放物后。数据表明，异戊二烯在受体植物中诱导类似于单萜诱导的防御反应，并且依赖于水杨酸（SA）信号。相比之下，倍半萜，β-石竹烯通过茉莉酸（JA）信号诱导抗性。在开放环境中的实验表明，自然生物排放足以诱导邻近的拟南芥产生抗性。我们的结果表明，异戊二烯和β-石竹烯都作为复杂植物信号网络中的化感成分发挥作用。了解该系统可能有助于在各种作物管理方案中提高植物对微生物病原体的免疫力。
