سبب شناسي بيماري پوسيدگي ريشه گل پريوش (Catharanthus roseus) در گلخانه‌هاي اصفهان با استفاده از روش‌هاي مورفولوژيكي و مولكولي

Catharanthus roseus is among the most important ornamental an‎d medicinal plants cultivated in greenhouses an‎d urban lan‎dscapes, with considerable economic value owing to its wide application an‎d pharmaceutical properties. However, soil-borne diseases, particularly root rot an‎d wilt, are major constraints on the production an‎d quality of this plant. The present study aimed to identify an‎d determine the etiology of fungal pathogens associated with root rot an‎d wilt of C. roseus in greenhouse production systems in Isfahan Province, using morphological, pathogenicity, an‎d molecular approaches. Sampling was conducted from plants showing symptoms such as yellowing, growth reduction, wilting, an‎d root decay. Fungal isolates were obtained using selec‎tive culture media an‎d subsequently purified. Preliminary identification was based on macroscopic an‎d microscopic characteristics, followed by pathogenicity tests to confirm the isolatesʹ disease-causing ability. For precise identification, genomic DNA was extracted, an‎d the ITS region, along with the TEF an‎d TUB2 gene regions, was amplified an‎d sequenced. The obtained sequences were analyzed in the NCBI database, an‎d phylogenetic trees were constructed using the Maximum-Likelihood method. The results revealed that Fusarium oxysporum, Fusarium solani, Fusarium equiseti, an‎d Fusarium verticillioides were the main causal agents of root rot an‎d wilt of periwinkle in the studied area. Pathogenicity assays confirmed the virulence of all identified isolates, while molecular analyses revealed high sequence similarity between the isolates obtained an‎d previously reported global reference strains. Overall, this study presents the first comprehensive report on the diversity of Fusarium species associated with periwinkle diseases under greenhouse conditions in Isfahan Province. The findings provide valuable baseline information for disease management strategies, breeding programs, an‎d the development of effective control measures against soil-borne pathogens affecting this important ornamental an‎d medicinal plant. Keywords: Catharanthus roseus, root rot, Fusarium, molecular identification, soil-borne diseases

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امير مساح

ابوذر سورني , صادق زارعي