Tsao Wei-Chin, Li Yi-Hsuan, Tu Yi-He, Nai Yu-Shin, Lin Tsung-Chun, Wang Chih-Li
Department of Plant Pathology, National Chung Hsing University, Taichung, Taiwan.
Doctoral Program in Microbial Genomics, National Chung Hsing University and Academia Sinica, Taichung, Taiwan.
Front Microbiol. 2024 Sep 24;15:1431813. doi: 10.3389/fmicb.2024.1431813. eCollection 2024.
Moth orchids ( spp.) are globally popular ornamental flowers. However, effective management strategies for leaf yellowing remain elusive, making the disease a challenging obstacle affecting moth orchids at various growth stages. This disease manifests as collar rot, leaf yellowing, leaf abscission, and eventually, plant death. The lack of effective management strategies is likely attributed to a limited understanding of the disease pathogenesis and pathogen dissemination pathways. sp. nov. was established in this study to stabilize the classification status of leaf yellowing pathogens using molecular and morphological features. The genome of the holotype strain was sequenced and assembled, revealing its genome structures. Analyses of virulence-related elements, including transposon elements, secondary metabolite biosynthetic gene clusters, effectors, and secreted carbohydrate-active enzymes, shed light on the potential roles of three fast core chromosomes in virulence. Two species-specific primers were designed based on unique gene sequences of two virulence-related proteins through comparative genomics and BLAST screening. The specificity of these primers was validated using isolates of , non-target species in the species complex, other species complexes, and saprophytic fungi. These results are intended to accelerate the identification of the pathogens, facilitate the study of disease pathogenesis, and pave the way for elucidating pathogen dissemination pathways. Ultimately, they aim to contribute to the formulation of effective control strategies against leaf yellowing.
蝴蝶兰（Phalaenopsis spp.）是全球广受欢迎的观赏花卉。然而，针对叶片发黄的有效管理策略仍然难以捉摸，这使得该病害成为影响蝴蝶兰各个生长阶段的一个具有挑战性的障碍。这种病害表现为颈部腐烂、叶片发黄、叶片脱落，最终导致植株死亡。缺乏有效的管理策略可能归因于对病害发病机制和病原体传播途径的了解有限。本研究中建立了新种（sp. nov.）以利用分子和形态学特征稳定叶片发黄病原体的分类地位。对模式菌株的基因组进行了测序和组装，揭示了其基因组结构。对与毒力相关的元件进行分析，包括转座子元件、次生代谢物生物合成基因簇、效应子和分泌的碳水化合物活性酶，揭示了三条快速核心染色体在毒力中的潜在作用。通过比较基因组学和BLAST筛选，基于两种与毒力相关蛋白的独特基因序列设计了两种物种特异性引物。使用尖孢镰刀菌（Fusarium oxysporum）的分离物、尖孢镰刀菌物种复合体中的非目标物种、其他镰刀菌物种复合体和腐生真菌验证了这些引物的特异性。这些结果旨在加速病原体的鉴定，促进病害发病机制的研究，并为阐明病原体传播途径铺平道路。最终，它们旨在为制定针对蝴蝶兰叶片发黄的有效防治策略做出贡献。
