First Report of Internal Fruit Rot of Sweet Pepper in Korea Caused by Fusarium lactis

Possibly the first case of onychomycosis by Fusarium lactis: Case presentation and literature review of onychomycosis by Fusarium species

Fusarium species (spp.) is frequently found in soil and plant residues and on plant bodies in all climatic zones worldwide. Although there have been few reports of onychomycosis caused by Fusarium spp., it is characterized by drug sensitivity and other characteristics. Here, we report what may be the first case of onychomycosis caused by Fusarium lactis. We analyzed the mycology and characterized previously reported cases of onychomycosis caused by Fusarium spp. A 73-year-old otherwise healthy woman presented with discoloration and thickening of her right thumbnail with paronychia. Direct microscopy revealed unevenly swollen hyphae, and a Grocott-stained nail specimen showed septate hyphae. Based on the morphological features and gene analysis of fungus isolated from the nail, we diagnosed onychomycosis caused by F. lactis belonging to Fusarium fujikuroi species complex. Partial nail removal and topical application of 1% luliconazole solution resolved the condition in 6 months. Minimum inhibitory concentrations for isolated F. lactis showed high sensitivity to luliconazole but not itraconazole or terbinafine. The isolated F. lactis was temperature-sensitive. A search of the literature revealed 57 cases of onychomycosis caused by Fusarium spp. with delineated clinical characteristics. Since those cases were investigated using morphological and/or molecular methods, we analyzed them by species complex as well as species. Onychomycosis caused by Fusarium spp. is predominantly found on the big toe, with Fusarium solani species complex and Fusarium oxysporum species complex accounting for over 70% of cases. Infection of only one digit with paronychia is a characteristic clinical manifestation of onychomycosis caused by Fusarium spp. Since there has been an increase in instances of molecular determination of Fusarium spp., it is deemed necessary to clarify its clinical and fungal nature. Due to its characteristic drug sensitivity and temperature-sensitive nature, new treatments are expected to be developed.

Species Composition and Toxigenic Potential of Fusarium Isolates Causing Fruit Rot of Sweet Pepper in China

Apart from causing serious yield losses, various kinds of mycotoxins may be accumulated in plant tissues infected by Fusarium strains. Fusarium mycotoxin contamination is one of the most important concerns in the food safety field nowadays. However, limited information on the causal agents, etiology, and mycotoxin production of this disease is available on pepper in China. This research was conducted to identify the Fusarium species causing pepper fruit rot and analyze their toxigenic potential in China. Forty-two Fusarium strains obtained from diseased pepper from six provinces were identified as F. equiseti (27 strains), F. solani (10 strains), F. fujikuroi (five strains). This is the first report of F. equiseti, F. solani and F. fujikuroi associated with pepper fruit rot in China, which revealed that the population structure of Fusarium species in this study was quite different from those surveyed in other countries, such as Canada and Belgium. The mycotoxin production capabilities were assessed using a well-established liquid chromatography mass spectrometry method. Out of the thirty-six target mycotoxins, fumonisins B₁ and B₂, fusaric acid, beauvericin, moniliformin, and nivalenol were detected in pepper tissues. Furthermore, some mycotoxins were found in non-colonized parts of sweet pepper fruit, implying migration from colonized to non-colonized parts of pepper tissues, which implied the risk of mycotoxin contamination in non-infected parts of food products.