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| Morphology of Cytospora discostoma (BJFC CF2019802). (A,B) Habit of conidiomata on twig. (C) Transverse section of conidioma. (D) Longitudinal section through conidioma. (E) Conidiophores and conidiogenous cells. (F) Conidia. (G) Colonies on PDA at 3 days (left) and 30 days (right). Bars: (A) = 1 mm; (B-D) = 500 µm; (E,F) = 10 µm.
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Cytospora species are widely distributed and often occur as endophytes, saprobes or phytopathogens. They primarily cause canker and dieback diseases of woody host plants, leading to the growth weakness or death of host plants, thereby causing significant economic and ecological losses. In order to reveal the diversity of Cytospora species associate...
Citations
... Cytospora is distributed worldwide and often known to be associated with plant diseases (Monkai et al. 2021;Pan et al. 2021;Lin et al. 2022;Travadon et al. 2022). ...
During our biodiversity investigations in Tibet, China, typical Cytospora canker symptoms were observed on branches of hosts Myricaria paniculate, Prunus cerasifera and Sibiraea angustata. Samples were studied, based on morphological features coupled with multigene phylogenetic analyses of ITS, act, rpb2, tef1 and tub2 sequence data, which revealed two new species (Cytospora myricicolasp. nov. and C. sibiraeicolasp. nov.) and a known species (C. populina). In addition, Cytospora populina is newly discovered on the host Prunus cerasifera and in Tibet.
... Cytospora species generally cause canker, dieback and decline diseases with different symptoms on a wide range of woody perennials including fruit and nut trees, forest and urban trees, and rarely on herbaceous plants with strong ecological adaptability 21,26,41,54,55 . In our study, disease symptoms differed from the previously reported symptoms of apple canker diseases caused by Cytospora species, as the disease starts from the crown and collar region of apple trees (Fig. 1). ...
... The results of our phylogenetic analyses using ITS-rDNA sequences placed C. balanejica together with C. albodisca, C. corylina, and C. olivacea in an unresolved clade, confirmed the poor utility of this genomic region in the differentiation of Cytospora species 21,38,61,62 ( Supplementary Fig. S1). Recent studies using a polyphasic approach, morphology, and multi-gene phylogeny, have revealed hidden fungal diversity, and led to the description of several new cryptic Cytospora species 21,23,26,38,41 . Based on our multi-gene phylogenetic analyses, C. balanejica formed a well-defined monophyletic lineage distinct from all other strains with close affinity to C. albodisca and C. corylina, two recently described Cytospora species (Fig. 2). ...
... ex. Trautv. in China showing canker and dieback symptoms, respectively 26,41 . ...
Apple is the most important fruit tree in West Azarbaijan province of Iran. In a survey of apple orchards, a disease with crown and collar canker and necrosis symptoms was observed in three young apple orchards in Urmia, affecting 15% and 1% of ‘Red Delicious’ and ‘Golden Delicious’ cultivars, respectively. A fungus with typical characteristics of the asexual morph of Cytospora was regularly isolated from the diseased tissues. Morphological characteristics and phylogenetic analyses inferred from the combined dataset of the ITS-rDNA, parts of LSU, tef1-α, rpb2, and act1 genes revealed that the isolates represent a new species of Cytospora, described herein as Cytospora balanejica sp. nov.. The pathogenicity of all isolates was confirmed on apple cv. ‘Red Delicious’ based on Koch’s postulates. Also, the reaction of 12 other apple cultivars was assessed against five selected isolates with the highest virulence. The results showed that except for cv. ‘Braeburn’, which did not produce any symptoms of the disease, the other 11 cultivars showed characteristic disease symptoms including sunken and discolored bark and wood. The mean length of the discolored area was different among the 11 so-called susceptible cultivars, hence cvs. ‘M4’ and ‘Golden Delicious’ showed the highest and the lowest lesion length, respectively. Moreover, the aggressiveness of the five tested isolates was different, and the isolates BA 2-4 and BA 3-1 had the highest and lowest aggressiveness, respectively. Based on our observations on the potential ability of the fungus to cause disease on young and actively growing apple trees, it will be a serious threat to apple cultivation and industry.
... Species of Cytospora were primarily identified and distinguished by their morphology and host [5][6][7]. However, recent studies employing molecular phylogeny revealed many cryptic species with similar morphology on the same host of known species of this genus [11][12][13][14][15]. For example, up to 28 Cytospora species were discovered from Eucalyptus spp. in South Africa with the help of DNA sequence evidence [2], eight from willow (Salix spp.) trees in China [16], six from Castanea mollissima in China [17], six from Populus hosts in China [18] and six from apple trees in Iran [19]. ...
... In the traditional classification and identification of species in Cytospora, spore morphology and host information are the most important evidence to identify Cytospora species [5][6][7]. However, by using the molecular data, many cryptic species with the same hosts and similar spore morphology were recently revealed [1, 14,15,35]. The molecular classification system for Cytospora based on morphology, phylogeny and host information is more scientific than that mainly based on morphology before. ...
Cytospora (Cytosporaceae, Diaporthales) is a fungal genus that usually inhabits plants as endophytes, saprobes, as well as pathogens. Species of this genus are characterized by possessing allantoid hyaline conidia and ascospores. Samples with typical Cytospora canker symptoms on Prunus davidiana, P. padus and Salix sp. were collected in Tibet and Xinjiang, China. Species were identified using both morphological and molecular approaches of combined loci of internal transcribed spacer region rDNA (ITS), the partial actin (act) region, RNA polymerase II second largest subunit (rpb2), the translation elongation factor 1-alpha (tef1) gene and the partial be-ta-tubulin (tub2) gene. Six isolates in the present study formed three distinct clades from previously known species. Cytospora hejingensis sp. nov. from Salix sp., C. jilongensis sp. nov. from P. davidiana and C. kunsensis from P. padus were proposed herein. The current study improves the understanding of species concept in Cytospora.
... As more plant species were recorded in this city, the exploration of fungal diversity gradually increased as most fungi are often linked to particular host plants as pathogens or endophytes. With the modern taxonomic approaches applying, more than 30 Cytospora species have been reported in the last five years in Beijing Pan et al. 2021;Lin et al. 2023a, b). Fengtai is one of the districts in Beijing with high forest cover and rich tree species which is located in the south-western suburbs of Beijing. ...
... (Ronquist and Huelsenbeck 2003) for Bayesian Inference (BI) analysis. For ML analysis, the substitution model (GTR+G+I model) for each dataset was selected following recent studies Pan et al. 2020Pan et al. , 2021. Confidence levels for the nodes were determined using 1,000 replicates of bootstrapping methods (Hillis and Bull 1993). ...
... ML bootstraps (ML BS ≥ 60%) and Bayesian posterior probabilities (BPP ≥ 0.90) have been shown above the branches (Fig. 2). For ML analysis, the substitution model (GTR+G+I model) for each dataset was selected following recent studies Pan et al. 2020Pan et al. , 2021. Confidence levels for the nodes were determined using 1,000 replicates of bootstrapping methods (Hillis and Bull 1993). ...
Members of Cytospora include saprobes, endophytes and important plant pathogens, which are widely distributed on various wood hosts and have a wide global distribution. In this study, the species definitions were conducted, based on multigene phylogeny (ITS, act , rpb2 , tef1-α and tub2 genes) and comparisons of morphological characters. A total of 22 representative isolates obtained from 21 specimens in Fengtai District of Beijing City were identified as seven species of Cytospora , including four known species ( C. albodisca , C. ailanthicola , C. euonymina , C. haidianensis ) and three novel species ( C. fengtaiensis , C. pinea , C. sorbariae ). The results provide an understanding of the taxonomy of Cytospora species associated with canker and dieback diseases in Fengtai District, Beijing, China.
... Cytospora is a species-rich genus of Diaporthales, which is often associated with plant diseases [35][36][37]. In recent publications, many cryptic new species of this genus were proposed based on evidence from combined morphology and phylogeny analyses [9,21,24,25,38]. Some of them have been proven to be the pathogens causing important diseases [21,24,25]. ...
Branch canker diseases are important in forest ecosystems, causing economic and ecological losses. Members of Cytospora are common on cankered branches and associated with the diseases. Investigations on Cytospora cankers were conducted in Tibet, China, during 2022 and 2023. Samples were collected from Euonymus japonicus, Larix gmelinii, Malus pumila, M. spectabilis and Rosa omeiensis f. pteracantha, and cultures were obtained and identified by morphological features and molecular phylogeny of a combination of internal transcribed spacer region rDNA (ITS), the partial actin (act) region, RNA polymerase II second largest subunit (rpb2) gene, the translation elongation factor 1-alpha (tef1) gene and the partial beta-tubulin (tub2) gene. As a result, a new species is proposed herein named Cytospora lhasaensis and four known species are described for the first time from Tibet, viz. C. euonymina, C. gigaspora, C. mali and C. schulzeri. The current research enhances our understanding of the Cytospora species associated with woody host diseases in Tibet, China.
... Species from the genus Cytospora are described as endophytes, saprotrophs, or phytopathogens. These pathogens cause cankers on the branches of various trees, such as peaches, nectarines, plums, ashes, maples, birches, and willows, and may lead to tree dieback [49]. The development of the pathogen is favored by stress factors, such as insect Forests 2023, 14, 1324 9 of 14 feeding or damage caused by hail, snow, or drought. ...
Prunus serotina is an important invasive plant species in Poland. It was introduced to European forests, even in places currently protected by law, such as national parks. One major factor contributing to the spread of this species is the lack of infecting pathogens and incomplete knowledge about the relationship between the plant and microorganisms. This study aimed to identify fungal communities collected from freshly cut stumps of live and dead black cherry tree specimens growing in a protected forest. The main working hypotheses were as follows: (i) fungal communities inhabiting the wood of dead and living trees will differ in diversity and the number of taxa; and (ii) saprotrophic fungi will dominate in the wood of dead tree stumps. This study applied Illumina sequencing based on the amplification of the fungal ribosomal ITSI region. The average number of sequences (OTU) obtained from the analysis of dead tree wood was 101,758, while that of living trees was 94,150. These sequences belonged to 312 taxa, among which 254 were isolated from the wood of dead trees and 171 from that of living trees. Among the saprotrophs on dead trees, the following species were identified: Stereum rugosum, Ganoderma adspersum, G. applanatum, Peniophora cinerea, and Ascocoryne cylichnium. On the other hand, in the wood of living trees, Cytospora leucostoma and Botrytis cinerea were the most abundant saprotrophic species. The fungal communities inhabiting the wood of dead and living trees differed in the diversity and abundance of taxa, thus confirming our hypothesis. The results of our research conducted in a protected area indicate that black cherry wood can be naturally colonized by many pathogen species that can further limit its expansion.
... Therefore, CFCC 55529 is identified as Cytospora ailanthicola. Notes: Cytospora albodisca was first discovered on Platycladus orientalis, whose ascostroma was surrounded by a black conceptacle [83]. In this study, two isolates (CFCC 56274 and 57538) converged into a separate little branch. ...
... Therefore, these two isolates are identified as Cytospora albodisca. Notes: Cytospora discostoma was first discovered on branches of Platycladus orientalis at Mentougou District in Beijing [83]. In this study, one isolate, CFCC 56276, clustered in a well-support clade (ML/BI = 100/1) with C. discostoma CFCC 53137 and 54368. ...
... Cytospora had the highest diversity of species associated with E. japonicus (11 species). The genus includes numerous important pathogens and saprophytic fungi on various hosts [32,33,83,96]. Branch and stem diseases frequently result in skin rot, dryness, and plant death [51,52,57,97]. ...
Euonymus japonicus tolerates the dry and frigid climate of Beijing, China, and effectively filters out particles during the winter. However, fungal infestation frequently causes extreme illness and can even lead to shrub death. In this study, 104 diseased E. japonicus specimens were collected from seven districts in Beijing. Seventy-nine isolates were identified as 22 fungal species in seven genera. The species were Aplosporella hesperidica, A. javeedii, A. prunicola, Botryosphaeria dothidea, Colletotrichum aenigma, Co. euonymi, Co. euonymicola, Co. gloeosporioides, Cytospora ailanthicola, C. albodisca, C. diopuiensis, C. discotoma, C. elaeagni, C. euonymicola, C. euonymina, C. haidianensis, C. leucostoma, C. sophorae, C. zhaitangensis, Diaporthe eres, Dothiorella acericola, and Pestalotiopsis chaoyangensis. On the basis of morphological and phylogenetic analyses, Colletotrichum euonymi, Co. euonymicola, Cytospora zhaitangensis, and Pestalotiopsis chaoyangensis were introduced as novel species. Colletotrichum euonymi, Co. euonymicola, and Pestalotiopsis chaoyangensis were subsequently confirmed as pathogens of E. japonicus leaves by pathogenicity testing. This study provides an important assessment of the fungi associated with diseases of E. japonicus in Beijing, China.
... The taxonomic species identification of Cytospora spp. is mainly based on morphological characteristics and molecular phylogenetic analysis. Recent studies described a number of new species of Cytospora on different hosts using multi-gene (ITS, LSU, act, tef1-α, tub2, and rpb2) phylogenetic analysis [5,[10][11][12]. This approach allows for the identification of cryptic and novel species within the genus. ...
... The ML and BI analyses based on a concatenated alignment of ITS, LSU, act and tef1-α from 119 strains of Cytosporaceae produced phylogenetic trees with similar topology to those in recent taxonomic studies of Cytospora [5,9,12]. The best scoring RAxML tree is depicted in Fig 2. The strains of C. paraplurivora obtained in this study are clustered together and formed a distinct clade with strong bootstrap support values (100% ML, 1.00 BP). ...
... Eucaliptus, Juglans, Malus, Olea, Pistacia, Platanus, Prunus, and Salix. [5,10,12,63,64]. Pathogenic species of Cytospora were mainly isolated from wood cankers. ...
A new species of Cytospora was isolated from cankered wood of Prunus spp. during a survey of orchards exhibiting symptoms of fruit tree decline syndrome in southern Ontario, Canada. We found isolates that are morphologically similar to species in the Cytosporaceae family, which is characterized by single or labyrinthine locules, filamentous conidiophores or clavate to elongate obovoid asci and allantoid, hyaline conidia. Multi-gene phylogenetic analysis of ITS, LSU, act and tef1- α showed that the isolates form a distinct clade, sister to Cytospora plurivora. Morphologically, our isolates showed differences in the length of conidia and culture characteristics compared to C. plurivora, suggesting the establishment of a new species. The species is described as Cytospora paraplurivora sp. nov. and placed in the family Cytosporaceae of Diaporthales. Additionally, we sequenced, assembled and characterized the genome of the representative isolate for this new species. The phylogenomic analysis confirms the species order and family level classification. C. paraplurivora sp. nov. has the potential to severely affect stone fruits production, causing cankers and dieback in stressed trees, and eventually leads to tree decline. Pathogenicity tests show that the species is pathogenic to Prunus persica var. persica.
... In these cases, sequences with high similarity from ex-type and non-type isolates were included for phylogenetic reference utilizing the BLASTn function in NCBI and extensive literature review. Accordingly, relevant reference sequences were retrieved from recent and comprehensive phylogenetic studies for isolates in the genus Cadophora [ Linnakoski et al., 2018;Walsh et al., 2018;Bien and Damm, 2020;Macia-Vicente et al., 2020;Aigoun-Mouhous et al., 2021;Chen et al., 2022;Koukol and Macia-Vicente, 2022); Supplementary Table 2], Cytospora [ Pan et al., 2020;Shang et al., 2020;Pan et al., 2021); B u n d h u n e t a l . , 2 0 2 1 ; M o g h a d a m e t a l . ...
Grapevine trunk diseases cause serious economic losses to grape growers worldwide. The identification of the causal fungi is critical to implementing appropriate management strategies. Through a culture-based approach, we identified the fungal species composition associated with symptomatic grapevines from wine grapes in southeastern Washington and table grapes in the southern San Joaquin Valley of California, two regions with contrasting winter climates. Species were confirmed through molecular identification, sequencing two to six gene regions per isolate. Multilocus phylogenetic analyses were used to identify novel species. We identified 36 species from 112 isolates, with a combination of species that are new to science, are known causal fungi of grapevine trunk diseases, or are known causal fungi of diseases of other woody plants. The novel species Cadophora columbiana , Cytospora macropycnidia , Cytospora yakimana , and Sporocadus incarnatus are formally described and introduced, six species are newly reported from North America, and grape is reported as a new host for three species. Six species were shared between the two regions: Cytospora viticola , Diatrype stigma , Diplodia seriata , Kalmusia variispora , Phaeoacremonium minimum , and Phaeomoniella chlamydospora . Dominating the fungal community in Washington wine grape vineyards were species in the fungal families Diatrypaceae, Cytosporaceae and Sporocadaceae, whereas in California table grape vineyards, the dominant species were in the families Diatrypaceae, Togniniaceae, Phaeomoniellaceae and Hymenochaetaceae. Pathogenicity tests demonstrated that 10 isolates caused wood discoloration similar to symptomatic wood from which they were originally isolated. Growth rates at temperatures from 5 to 35°C of 10 isolates per region, suggest that adaptation to local climate might explain their distribution.
... Cytospora spp. mainly cause canker and die-back on more than 100 hardwood plant species, while some species have been isolated as saprobes or endophytes (Bills 1996;Christensen 1940;Fan et al., 2020;Monkai et al., 2021;Pan et al., 2018Pan et al., , 2020Pan et al., , 2021Spielman 1983). Even though Cytospora species are principally known as weak pathogens, they negatively affect the longevity and productivity of fruit trees worldwide and cause chronic wood infections on fruit trees such as Malus spp. ...
... For example, sequence data of tef1-a provided ample evidence to delineate C. vinacea and C. viticola in comparison with ITS region (Lawrence et al., 2017b). Recently, combined multi-locus DNA sequence data such as internal transcribed spacer (ITS), large nuclear ribosomal RNA subunit (LSU), actin (act), RNA polymerase II subunit (rpb2), translation elongation factor 1-alpha (tef1-a), and beta-tubulin (tub2) have been used to resolve phylogeny of Cytospora spp., which have led to description of several novel species (Fan et al., 2014a(Fan et al., , 2014b(Fan et al., , 2015a(Fan et al., , 2015bJami et al., 2018;Jiang et al., 2020;Lawrence et al., 2017bLawrence et al., , 2018Norphanphoun et al., 2017Norphanphoun et al., , 2018Pan et al., 2018Pan et al., , 2020Pan et al., , 2021Senanayake et al., 2017Senanayake et al., , 2018Wang et al., 2015;Yang et al., 2015;Zhang et al., 2014;Zhu et al., 2018Zhu et al., , 2020. Therefore, a DNA-based approach using several gene regions would be the best method to resolve Cytospora species concepts, especially when morphological features and host association criteria are confused due to significant overlap (Lawrence et al., 2018). ...
In recent years, canker and die-back diseases have become a growing threat for the productivity and longevity of apple orchards in Iran. In this study, 131 Cytospora isolates were recovered from symptomatic tissues of apple trees in apple orchards of Iran. Multigene phylogenetic inference based on combined sequence data of ITS, act, rpb2, and tef1-α loci, supplemented with morphological characteristics and pathogenicity assay revealed four novel Cytospora species which were described as C. avicennae, C. azerbaijanica, C. ershadii, and C. iranica, and four known species, namely C. chrysosperma, C. parasitica, C. paratranslucens, and C. sorbicola. Also, C. sorbicola is newly reported on apple trees worldwide. Koch's postulates were fulfilled to confirm that all eight species in this study were pathogenic on apple trees in Iran, among which C. sorbicola was the most intensive species. The results of this study further highlight rich diversity among Cytospora species occurring on apple trees, revealing several novel Cytospora species on this host. The host range, geographical distribution, and economic significance of novel species on apple industry remains to be studied.
