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Fusarium citricola CBS 142421. a-b. Colonies on PDA and OA, respectively, after 7 d at 24 °C in the dark; c. colony on PDA after 7 d at 24 °C under continuous white light; d-e. sporodochia formed on the surface of carnation leaves; f-h. sporodochial conidiophores and phialides; i-j. aerial conidiophores; k-n. aerial phialides; o. aerial conidia (microconidia); p. sporodochial conidia (macroconidia).-Scale bars = 10 µm (scale bar in j also applies to k-n).
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The diversity of fusaria in symptomatic Citrus trees in Greece, Italy and Spain was evaluated using
morphological and molecular multi-locus analyses based on fragments of the calmodulin (CAM), intergenic spacer region of the rDNA (IGS), internal transcribed spacer region of the rDNA (ITS), large subunit of the rDNA (LSU), RNA polymerase largest sub...
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... Fusarium species have also been detected at high relative abundance in the soil samples. This genus includes several soil-borne fungal pathogens, such as Fusarium solani, which is known to cause wood dry rot in citrus trees [59]. Other species within the Fusarium genus are responsible for significant yield losses by causing root rot and wilts in various economically important crops [60][61][62]. ...
Mal secco is a vascular disease of citrus caused by the mitosporic fungus Plenodomus tracheiphilus. Soil containing infected plant material constitutes an inoculum source for root infections. In this study, the soil bacterial and fungal communities of five lemon orchards located in Syracuse Province (Sicily, Italy) affected by mal secco were analyzed. Soil samples were collected under lemon tree canopies and subjected to total genomic DNA extraction. The fungal DNA was detected through qPCR in all orchards, with variable concentrations. Bacterial and fungal communities were profiled using 16S and ITS amplicon-based high-throughput sequencing, respectively. According to our results, the relative abundances of the most represented bacterial phyla (e.g., Proteobacteria, Actinobacteriota, Acidobacteriota) changed across the orchards, while in the fungal community, the phylum Ascomycota was dominant, with Basidiomycota and Mortierellomycota abundances fluctuating. On the whole, β diversity analysis showed significant variation in the composition of the soil microbial communities across the orchards. This result was confirmed by the analysis of the core community (taxa present at ≥ 75% of total samples), where putative beneficial bacteria resulted in significantly enriched fungus-infected soil samples, suggesting complex microbial interactions. Our findings shed light on the composition and diversity of the soil microbiome in lemon orchards with the occurrence of mal secco infections.
... The proponent of biogeographic hypothesis for FFSC [19] clustered Fusarium isolates into three clusters with wellsupported phylogenetic clades named the African, American, and Asian clades. The core African clade included maize and coffee pathogens such as F. verticillioides and F. xylarioides [20,21,22]. Presently, there are more than 60 distinct phylogenetic species recognized under FFSC [23]., F. verticillioides is the most predominant species of Fusarium in maize-growing areas of India [24,6]. ...
Fusarium stalk rot (FSR) caused by the Fusarium species complex is an economic threat to maize cultivation all over the world. We investigated the population structure and genetic diversity of Fusarium spp. obtained from five major maize-growing regions of India. The Tef-1α locus was used for phylogenetic analysis of geographically distinct isolates of Fusarium verticillioides, F. andiyazi, F. proliferatum, F. nygamai, and F. acutatum causing FSR. Geographical separation among four local populations contributed to 7.87% variance, whereas 92.12% of the variance was within popula-tions, suggesting a predominant influence of local adaptation or stochastic events like genetic drift within populations, with geographical separation playing a lesser but significant role in shaping genetic diversity. Genetic differentiation statistics between Fusarium species showed lower gene flow from haplotypes except in the population of F. acutatum and F. andiyazi having high GST values. In contrast, a high Kxy was reported, indicating elevated genetic differentiation between populations. The haplotype network analysis revealed the presence of eight distinct haplotypes which reflected pathogenic evolution and adaptive potential of Fusarium spp. The results offer a comprehensive framework for discussing the implications of genetic diversity in pathogen management and the evolutionary dynamics of the Fusarium spp. causing FSR of maize in the Indian subcontinent.
... The morphological characteristics and expression of anthracnose described in this study are similar to those of Colletotrichum gloeosporioides observed and described by Honger et al. (2016); Rhaiem and Taylor (2016). As for Curvularia sp. and Fusarium sp., symptoms similar to those described in this study have already been described by many authors (Kunta et al., 2015;Sandoval-Denis et al., 2018). However, the pathogenicity test carried out with isolates of Curvularia sp. and Fusarium sp. on fruit gave a negative result. ...
Fungal diseases are a major constraint for the intensification of citrus production in Benin. The aim of this study was to identify the main citrus fungal diseases and to assess their distribution, prevalence, and severity). A total of 315 orchards were surveyed in the four agro-ecological zones (AEZ V, VI, VII, and VIII) where citrus is produced in Benin. During the surveys, samples of diseased fruits were collected for isolation in the laboratory. The results revealed four main fungal diseases including black spot caused by Phyllosticta sp., anthracnose caused by Colletotrichum sp., brown rot disease caused by Curvularia sp., and fruit rot caused by Fusarium sp. Among these diseases, black spot is the most distributed with 76.69% infected plants as compared to anthracnose, brown rot disease and fruit rot which infected 32.4%, 6.3% and 1.9% of plants respectively. The diseases severity was 2.88, 1.46, 1.08 and 0.60 for black spot, anthracnose, brown rot and fruit rot respectively. Of the three cultivated varieties, Pineapple and Valencia were susceptible to the four diseases while the variety Tangelo was less susceptible. The highest severity (3.51) was recorded in the AEZ VI and the lowest (0.81) in the AEZ VII. This study showed that citrus tree was susceptible to several diseases in Benin with black spot disease caused by Phyllosticta sp., as the most important. Any effort to increase qualitatively and quantitatively citrus productivity should be based on sustainable management of diseases
... Fusarium solani was first isolated from potato with dry rot in 1842 in Germany and described as the pathogen causing this disease. Currently, there are more than 70 recognized phylogenetic species of the FSSC, while some of them do not yet have formal descriptions or Latin binomial names [46][47][48][49]. The Fusarium solani species complex is the most controversial group of fungi, both in terms of its intraspecific diversity and its degree of relatedness to the genus Fusarium s. str. ...
Dry rot of potato tubers is a harmful disease caused by species of the Fusarium genus. Studies on the composition and features of Fusarium spp. that cause the disease in Russia are limited. Thirty-one Fusarium strains belonging to the F. sambucinum species complex (FSAMSC) and F. solani species complex (FSSC) were accurately identified using multilocus phylogenetic analysis of the tef and rpb2 loci, and their physiological characteristics were studied in detail. As a result, 21 strains of F. sambucinum s. str. and 1 strain of F. venenatum within the FSAMSC were identified. Among the analyzed strains within the FSSC, one strain of F. mori, four strains of F. noneumartii, and two strains of both F. stercicola and F. vanettenii species were identified. This is the first record of F. mori on potato as a novel host plant, and the first detection of F. noneumartii and F. stercicola species in Russia. The clear optimal temperature for the growth of the strains belonging to FSAMSC was noted to be 25 °C, with a growth rate of 11.6–15.0 mm/day, whereas, for the strains belonging to FSSC, the optimal temperature range was between 25 and 30 °C, with a growth rate of 5.5–14.1 mm/day. The distinctive ability of F. sambucinum strains to grow at 5 °C has been demonstrated. All analyzed Fusarium strains were pathogenic to potato cv. Gala and caused extensive damage of the tuber tissue at an incubation temperature of 23 °C for one month. Among the fungi belonging to the FSAMSC, the F. sambucinum strains were more aggressive and caused 23.9 ± 2.2 mm of necrosis in the tubers on average compared to the F. venenatum strain—17.7 ± 1.2 mm. Among the fungi belonging to the FSSC, the F. noneumartii strains were the most aggressive and caused 32.2 ± 0.8 mm of necrosis on average. The aggressiveness of the F. mori, F. stercicola, and especially the F. vanettenii strains was significantly lower: the average sizes of damage were 17.5 ± 0.5 mm, 17.2 ± 0.2 mm, and 12.5 ± 1.7 mm, respectively. At an incubation temperature of 5 °C, only the F. sambucinum strains caused tuber necroses in the range of 6.7 ± 0.5–15.9 ± 0.8 mm.
... The Fusarium species were isolated based on morphological features alone and confronted several discrepancies, as frequently observed in previous studies [48]. Currently, the species identified by the PCR assay and sequence are required for accurate taxonomical characterization, including the Fusarium species [35]. ...
Leaf-blight disease caused by the Fusarium oxysporum is an emerging problem in Dendrobium chrysotoxum production in China. Symptoms of leaf blight were observed on seedlings of D. chrysotoxum cultivated in a nursery in Ruili City, Yunnan Province, China. In this study, we isolated the Fusarium sp. associated with leaf-blight disease of D. chrysotoxum from the diseased seedlings. A pathogenicity test was performed to fulfill Koch’s postulates to confirm the pathogenicity of isolated strains and identified using morphological and molecular techniques. The results revealed that all four isolated Fusarium sp. isolates (DHRL-01~04) produced typical blight symptoms followed by marginal necrosis of leaves on the D. chrysotoxum plants. On the PDA medium, the fungal colony appeared as a white to purplish color with cottony mycelium growth. Microconidia are oval-shaped, whereas macroconidia are sickle-shaped, tapering at both ends with 2–4 septations. The phylogenetic trees were construed based on internal transcribed spacer (ITS), translation elongation factor (EF-1α), and RNA polymerase subunit genes RPB1 and RPB2 genes, respectively, and blasted against the NCBI database for species confirmation. Based on the NCBI database’s blast results, the isolates showed that more than 99% identify with Fusarium oxysporum. To our knowledge, this is the first comprehensive report on the identification of Fusarium oxysporum as the causal agent of Dendrobium chrysotoxum leaf blight in Yunnan Province, China, based on morphological and molecular characteristics.
... Frost damage, sun scald, or irregular water distribution affect infection by Ascomycetes and Basidiomycetes (Timmer et al., 2000). Several trunk pathogens are known to cause diseases of citrus in Europe (Guarnaccia and Crous, 2017;Sandoval et al., 2018;Leonardi et al., 2023), and focus has been given to Botryosphaeriaceae. Several species of Diplodia, Dothiorella, Lasiodiplodia, Neofusicoccum, and Neoscytalidium have been documented as affecting citrus hosts (Figure 8 h). ...
Many fungi belonging to Botryosphaeriaceae are well-known as causal agents of diseases in economically and ecologically important agricultural crops and forest trees. In Italy, the high diffusion of Botryosphaeriaceae infections observed over the last decade, has shown the importance of this group of fungi, which are becoming limiting factors for plant production in agricultural systems, nurseries and natural and urban landscapes. Global warming and stress factors such as occasional extreme climatic events can affect the susceptibility of host plants, as well as fungus behaviour, increasing the risk of future infections. Available reports of Botryosphaeriaceae in Italy have been examined, focusing on wood and fruit pathogens, resulting in a list of ten genera and 57 species. Diplodia is the most widespread genus in Italy with 76 records on 44 hosts, while at species level, Neofusicoccum parvum, Botryosphaeria dothidea and Diplodia seriata show the widest host ranges and many records. The ability of the pathogens to remain latent on asymptomatic plants, and uncontrolled trade of plant materials among countries, facilitate the dissemination and potential introduction of new Botryosphaeriaceae species. Preventive detection and adequate control strategies are always needed to limit the potential damage caused by Botryosphaeriaceae. This review had particular emphasis on host-pathogen associations, disease symptoms, geographic distribution, metabolite production, and accurate pathogen identification.
... Fusarium species along with other abiotic stresses such as soil structure, salinity, moisture content, and root zone damage can be very destructive. Sandoval-Denis et al. (2018) reported sudden wilting in citrus trees caused by F. solani in addition to the negative impacts of abiotic and biotic stresses. The negative impact of Fusarium spp. on citrus was more severe under the combined effects of additional biotic (Phytophthora species and some nematodes) and abiotic (drought, disruption of oxygen balance in the root zone due to over-irrigation, and excess use of fertilizers) stress factors (Yaseen and D'Onghia 2012). ...
... The morphological diagnosis of fungi was carried out under a light microscope. The diagnostic features were colony colour and growth rate on medium, colour and division of hyphae, shape of phialides, presence and dimensions of macro and micro conidia, presence of chlamydospores and macro and micro sclerotia formation (Booth 1977;Burgess and Liddell 1983;Barnett and Hunter 1998; Beas-Fernandez et al. 2006;Leslie and Summerell 2006;Balajee et al. 2009;Geiser et al. 2013;Salah et al. 2015;Nouri et al. 2020). The structures and characteristics of each isolate were visualized under a light microscope. ...
... The sequences generated in this research were analyzed with the NCBI's GenBank database through the BLAST-N program to determine the closest species and the species complexes to which they belong and then compared with reference sequences reported in the literature [16][17][18][19]24,39,44,[62][63][64][65][66][67][68][69] and downloaded from GenBank to establish the identity of the explored isolates. All the different regions of the sequences in this study and those downloaded from GenBank were aligned with the MAFFT v. 7 online server (http://mafft.cbrc.jp/alignment/server/index.html, ...
... Single conidia colonies of the 23 representative isolates were grown on PDA for 10 days. Colony growth and macromorphological features were determined by placing agar plugs (5 mm) taken from the edge of actively growing cultures on PDA plates and incubating at 25 ± 1 • C under 12/12 h near-UV light for 7 days [69]. All the isolates were transferred onto carnation leaf agar (CLA) plates [75] and incubated at 25 ± 1 • C under 12/12 h near-UV light for 14 days to induce sporulation. ...
The genus Fusarium includes several agronomically important and toxin-producing species that are distributed worldwide and can cause a wide range of diseases. Crown and stalk rot and grain infections are among the most severe symptoms that Fusarium spp. can cause in maize. Disease development usually occurs during germination, but it may also affect the later phases of plant growth. The purpose of this study was to investigate the diversity and pathogenicity of 41 isolates recovered from symptomatic seedlings collected in Northern Italy and seeds of five different geographical origins in 2019 and 2020. The pathogenicity was tested and confirmed in 23 isolates causing rotting in maize seedlings, with disease indexes from 20% to 90%. A multilocus phylogeny analysis based on four genomic loci (tef1-α, rpb2, calm and tub2) was performed on 23 representative isolates. Representative isolates were identified as species belonging to three species complexes (SC), including Fusarium verticillioides and F. annulatum in the F. fujikuroi SC. Fusarium commune was identified in the F. nisikadoi SC, and three different lineages were found in the Fusarium oxysporum SC. This study reports F. annulatum and two lineages of the Fusarium oxysporum SC as maize pathogens for the first time in Italy.
... The sequences generated in this research were analyzed with the NCBI's GenBank database through the BLAST-N program to determine the closest species and the species complexes to which they belong and then compared with reference sequences reported in the literature [16][17][18][19]24,39,44,[62][63][64][65][66][67][68][69] and downloaded from GenBank to establish the identity of the explored isolates. All the different regions of the sequences in this study and those downloaded from GenBank were aligned with the MAFFT v. 7 online server (http://mafft.cbrc.jp/alignment/server/index.html, ...
... Single conidia colonies of the 23 representative isolates were grown on PDA for 10 days. Colony growth and macromorphological features were determined by placing agar plugs (5 mm) taken from the edge of actively growing cultures on PDA plates and incubating at 25 ± 1 • C under 12/12 h near-UV light for 7 days [69]. All the isolates were transferred onto carnation leaf agar (CLA) plates [75] and incubated at 25 ± 1 • C under 12/12 h near-UV light for 14 days to induce sporulation. ...
The genus Fusarium includes several agronomically important and toxin-producing species, that are worldwide distributed and can cause a wide range of diseases. Crown and stalk rots and grain infections are among the most severe symptoms that Fusarium spp. can cause on maize. The disease development usually occurs during germination, but it may also affect the later phases of plant growth. The purpose of this study was to investigate the diversity and the patho-genicity of 41 isolates recovered from symptomatic seedlings collected in Northern Italy, and from seeds with five different geographical origins during 2019 and 2020. The pathogenicity was tested and confirmed on 23 isolates causing rotting on maize seedlings. A multi-locus phylogeny analysis, based on four genomic loci (tef1-α, rpb2, calm and tub2), was performed for 23 repre-sentative isolates. Representative isolates were identified as species belonging to three species complexes (SC). Fusarium verticillioides and F. annulatum in the F. fujikuroi SC. Fusarium commune was identified in the F. nisikadoi SC, and three different lineages were found in the Fusarium ox-ysporum SC. This study reports F. annulatum, and two lineages of the Fusarium oxysporum SC as maize pathogens for the first time in Italy.
... Aspergillus fumigatus was also referred to as a "dilemma for clinical management" because of its high level of resistance and environmental adaptability [31]. Fusarium is known to adore moisture and frequently develops on fruits with high moisture content, including several citrus varieties [32]. ...
Background: In all of Pakistan's citrus-growing regions, losses related to fungi that cause infections of citrus fruits were investigated. However, the Khanpur city of the Haripur district, a significant citrus-growing area in Pakistan, has not addressed this issue. Citrus fruit quality and quantity deteriorate as a result of various fungi impairing their quiet standards, resulting in economic losses.
Results: The current investigation involves three steps that are morphological, pathological, and molecular identification of the fungal pathogens linked to citrus fruit diseases. Firstly the pathogens from infected fruit samples were isolated by culturing them on potato dextrose agar (PDA) for morphological characterization. Secondly, the 5.8S rDNA molecular sequencing was used to identify the crucial species at the molecular level. The results showed that they belonged to the seven important genera of Colletotrichum, Alternaria, Aspergillus, Botryosphaeria, Lasiodiplodia, Penicillium, and Fusarium. And thirdly the three different citrus cultivars were subjected to pathogenicity assays to identify the most resistant variety to fungal diseases.
Conclusions: Current work associated with the comprehension of disease development points towards effective managerial practices in the form of a cost-effective spray program. Furthermore, the findings are indicative of the need for biological and physical pre-harvest management interventions to increase storage and marketability.
