棕榈疫霉,一种半营养性卵菌,导致几种经济上重要的热带作物的疾病,比如油棕,它导致了一种叫做芽腐烂(BR)的毁灭性疾病。尽管最近在理解宿主抗性和毒力机制方面取得了进展,从油棕分离出的棕榈假单胞菌的许多方面仍然未知。模型病理系统对于理解病原体和宿主之间的分子相互作用是有用的。在这项研究中,我们利用拟南芥Col-0的离体叶片和整株幼苗来描述和评估引起油棕BR的三种棕榈假单胞菌分离株(CPPhZC-05,CPPhZC-04,CPPhZOC-01)的感染过程。两个相容的分离株(CPPhZC-05和CPPhZOC-01)在接种后72小时(hpi)诱导了房水损伤,通过微观可视化显示,游动孢子在3hpi时被包裹和附着体渗透,其次是72hpi的孢子囊代。相比之下,不相容的分离株(CPPhZC-04)表现出不能穿透组织的囊肿,导致低叶定殖。通过RT-qPCR定量10个掌形虫感染相关基因的基因表达,揭示相容分离株中的过表达,但不是在不兼容的隔离中。此外,与水杨酸(SA)相关的关键基因,茉莉酸(JA),拟南芥中的乙烯(ET)在与三个分离株的相互作用中表现出调节作用。这些发现表明,棕榈假单胞菌可以感染拟南芥Col-0,并且在拟南芥-Col-0和棕榈假单胞菌之间的相互作用中观察到变异性。建立该病理系统有望增强我们对棕榈假单胞菌的病理和生理学的理解。
Phytophthora palmivora, a hemibiotrophic oomycete, causes diseases in several economically important tropical crops, such as oil palm, which it is responsible for a devastating disease called bud rot (BR). Despite recent progress in understanding host resistance and virulence mechanisms, many aspects remain unknown in P. palmivora isolates from oil palm. Model pathosystems are useful for understanding the molecular interactions between pathogens and hosts. In this study, we utilized detached leaves and whole seedlings of Arabidopsis thaliana Col-0 to describe and evaluate the infection process of three P. palmivora isolates (CPPhZC-05, CPPhZC-04, CPPhZOC-01) that cause BR in oil palm. Two compatible isolates (CPPhZC-05 and CPPhZOC-01) induced aqueous lesions at 72 h post-inoculation (hpi), with microscopic visualization revealing zoospore encysting and appressorium penetration at 3 hpi, followed by sporangia generation at 72 hpi. In contrast, an incompatible isolate (CPPhZC-04) exhibited cysts that could not penetrate tissue, resulting in low leaf colonization. Gene expression of ten P. palmivora infection-related genes was quantified by RT-qPCR, revealing overexpression in compatible isolates, but not in the incompatible isolate. Additionally, key genes associated with salicylic acid (SA), jasmonic acid (JA), and ethylene (ET) in Arabidopsis exhibited regulation during interaction with the three isolates. These findings demonstrate that P. palmivora can infect Arabidopsis Col-0, and variability is observed in the interaction between Arabidopsis-Col-0 and P. palmivora isolates. Establishing this pathosystem is expected to enhance our understanding of P. palmivora\'s pathology and physiology.