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Comparison of Phyllosticta and Guignardia states. a Vertical section through pycnidium. b Pycnidial wall with conidiogenous cells. c Conidia. d Section of ascoma. e Bitunicate and fissitunicate ascus. f
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Phyllosticta is an important coelomycetous plant pathogenic genus known to cause leaf spots and various fruit diseases worldwide on a large range of hosts. Species recognition in Phyllosticta has historically been based on morphology, culture characters and host association. Although there have been several taxonomic revisions and enumerations of s...
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... pycnidia are usually globose, subglobose or tympaniform, flattened above, and closely connected with the subepidermal pseudostroma (Fig. 3a, b). They are mostly unilocular but occasionally may be multilocular (van der Aa 1973). The conidia are commonly hyaline, one-celled, ovoid, obovate or ellipsoid, or short cylindrical, seldom pyriform, globose or subglobose, 10-25 μm long, and usually covered by a slime layer and bearing a single apical appendage ( Fig. 3c) (van der Aa ...
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... pseudostroma (Fig. 3a, b). They are mostly unilocular but occasionally may be multilocular (van der Aa 1973). The conidia are commonly hyaline, one-celled, ovoid, obovate or ellipsoid, or short cylindrical, seldom pyriform, globose or subglobose, 10-25 μm long, and usually covered by a slime layer and bearing a single apical appendage ( Fig. 3c) (van der Aa 1973). Cultural characteristics when grown on specific media may also be used as differentiating characters. In the case of P. citricarpa colonies can be characterised after 14 days at 25°C in the dark on OA as flat, spreading, olivaceous-grey, becoming pale olivaceous-grey towards the margin, with sparse to moderate ...
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... soid, with a wide, slightly square apex, tapering gradually to a small pedicel, and with a well- developed ocular chamber. Ascospores are ellipsoid to limoniform, sometimes slightly elongated, aseptate, hyaline, often guttulate or with a large central guttule, and some have mucilaginous polar appendages (van der Aa 1973;Wulandari et al. 2011, Fig. ...
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... spermatial state is often present in the life cycle of Guignardia species, and readily forms in culture. Spermatia are cylindrical to dumbbell-shaped with guttules at each end (Fig. 3g). In the past several spermatial states were officially named. For instance, the spermatial state of Melanops concinna Syd. (= Guignardia concinna (Syd.) Aa; van der Aa 1973) was described as Leptodothiorella concinna Sydow ...
Citations
... Ascospores are aseptate, hyaline, ellipsoidal to limoniform, guttulate, and smooth-walled, with a mucoid cap at both ends (van der Aa 1973, Wong et al. 2012, Wikee et al. 2013a. Conidia of Phyllosticta are generally aseptate, hyaline, ovoid to ellipsoidal, globose to subglobose, surrounded by a mucilaginous sheath, bearing an apical appendage (van der Aa 1973, Wikee et al. 2011). However, the sheath and appendages are not present in all species e.g., P. minima and P. paviae lack a sheath and appendage (Wikee et al. 2013a). ...
... This huge number might be attributed to the addition of Phyllosticta taxa based on host association over the past 200 years. Also, Phyllosticta species were previously delineated based on morphology, thereby placing many species having hyaline, unicellular conidia similar to those of Phoma, either in the genera Phoma or Phyllosticta (Wikee et al. 2011). However, several of these species have been synonymized (van der Aa & Vanev 2002). ...
... However, further research is required to confirm this statement because they exhibit different lifestyles. Some species are host genus or family specific when they manifest as pathogens while as endophytes, most species tend to be generalists (Wikee et al. 2011. Phyllosticta is one of the important cryptic fungal phytopathogens with species complexes (Cai et al. 2011). ...
Phyllosticta is a cosmopolitan group of fungi found on various host plants, occurring as pathogens, endophytes and saprobes. Diseases caused by Phyllosticta commonly include leaf and fruit spots that can affect economically important plants. The genus is characterized mainly by aseptate and hyaline conidia and ascospores. Its conidia are surrounded by a mucilaginous sheath, with a single mucoid apical appendage while ascospores exhibit a mucoid cap at both ends. Given that many Phyllosticta taxa are cryptic and share similar morphologies, it is arduous to depict taxonomically relevant characters solely on the basis of morphological or ecological features. Coupled with morphological description, multi-locus phylogenetic analyses of species comprising complexes are used to broadly describe this genus and understand species boundaries. Despite several published taxonomic revisions and enumerations of Phyllosticta species, there is still considerable confusion when identifying these taxa. Herein, we establish three new host records for P. capitalensis, and one new geographical record for P. musaechinensis in Thailand, and one new host and geographical record for P. citribrasiliensis in Russia. We provide an updated phylogenetic tree based on several gene markers: ITS, LSU, ACT, GAPDH, RPB2, and TEF-1α. This includes all Phyllosticta species for which sequence data is available. Six individual Phyllosticta species complexes are accepted. In addition, we synonymize P. ericarum with P. citribrasiliensis.
... However, the multi-locus phylogenetic tree provided better resolution for the Phyllosticta species. Including proteincoding genes in the analysis greatly facilitated species-level identification, also demonstrated by Wikee et al. (2011). Multi-locus phylogeny and three signal locus (ITS, tef1, and act) supported the four new species. ...
... lanceolata. In addition, host specialisation in Phyllosticta may be related to lifestyle, and the endophytic fungus is less host-specific than the pathogenic fungus (Wikee et al. 2011); thus, P. capitalensis has a wider host range, which may be related to its endophytic lifestyle. A more indepth study of whether there is host specificity and how it relates to fungal lifestyle would require a comparative analysis of genomic data, such as comparing the number and type of carbohydrateactive enzymes. ...
Phyllosticta (Phyllostictaceae, Botryosphaeriales) species are widely distributed globally and constitute a diverse group of pathogenic and endophytic fungi associated with a broad range of plant hosts. In this study, four new species of Phyllosticta, i.e. P. endophytica, P. jiangxiensis, P. machili, and P. xinyuensis, were described using morphological characteristics and multi-locus phylogeny based on the internal transcribed spacer region (ITS) with intervening 5.8S rRNA gene, large subunit of rRNA gene (nrLSU), translation elongation factor 1-alpha gene (tef1), actin gene (act), and glycer-aldehyde-3-phosphate dehydrogenase gene (gapdh). Phyllosticta machili is the first species of this genus reported to infect plants of the Machilus genus. ARTICLE HISTORY
... Conidia of Phyllosticta are generally aseptate, hyaline, ovoid to ellipsoidal, globose to sub-globose, surrounded by a mucilaginous sheath, bearing an apical appendage (van der Aa 1973;Wikee et al. 2011). However, the sheath and appendages are not present in all species e.g., P. minima and P. sphaeropsoidea lack a sheath and appendage (Wikee et al. 2013a). ...
... tend to be generalists(Wikee et al. 2011;Bhunjun et al. 2022). One of the important cryptic fungal phytopathogens with species complexes is Phyllosticta(Cai et al. 2011). ...
Phyllosticta is a cosmopolitan group of fungi found on various host plants, occurring as pathogens, endophytes and saprobes. Diseases caused by Phyllosticta commonly include leaf and fruit spots that affect economically important plants. The genus is characterized mainly by aseptate and hyaline conidia and ascospores. However, its conidia are surrounded by a mucilaginous sheath, with a single mucoid apical appendage while ascospores exhibit a mucoid cap at both ends. Given that many Phyllosticta taxa are cryptic and share similar morphological features, it is arduous to depict taxonomically relevant characters solely on the basis of morphological and ecological features. Coupled with morphological description, multi-locus phylogenetic analyses of species comprising complexes are used to broadly describe this genus and understand species boundaries. Despite several published taxonomic revisions and enumerations of Phyllosticta species, there is still considerable confusion when identifying these taxa. Herein, we introduce a new species ( P. chiangmaiensis ) and three new host records ( P. capitalensis ) in Thailand, and one new host and country record ( P. citribrasiliensis ) in Russia. We provide an updated phylogenetic tree, including all Phyllosticta species with sequence data.
... Recently, Pseudofusicoccum was added in this family based on the morphological characters of the conidia covered by a mucous sheath and molecular evidence . The asexual morph of Phyllosticta is characterized by pycnidial conidiomata containing aseptate conidia surrounding with a mucoid layer and bearing a single apical appendage (van der Aa 1973; van der Aa and Vanev 2002; Wikee et al. 2011). The sexual morph of Phyllosticta is characterized by erumpent ascomata, 8-spored, clavate to broadly ellipsoid asci, ellipsoid to limoniform ascospores (van der Aa 1973; Wikee et al. 2011). ...
... The asexual morph of Phyllosticta is characterized by pycnidial conidiomata containing aseptate conidia surrounding with a mucoid layer and bearing a single apical appendage (van der Aa 1973; van der Aa and Vanev 2002; Wikee et al. 2011). The sexual morph of Phyllosticta is characterized by erumpent ascomata, 8-spored, clavate to broadly ellipsoid asci, ellipsoid to limoniform ascospores (van der Aa 1973; Wikee et al. 2011). Following the implementation of "one fungus one name" nomenclature rules, the name Phyllosticta (asexual state) was used over Guignardia (sexual state) and Leptodothiorella (spermatial state) (Glienke et al. 2011;Wikee et al. 2011). ...
... The sexual morph of Phyllosticta is characterized by erumpent ascomata, 8-spored, clavate to broadly ellipsoid asci, ellipsoid to limoniform ascospores (van der Aa 1973; Wikee et al. 2011). Following the implementation of "one fungus one name" nomenclature rules, the name Phyllosticta (asexual state) was used over Guignardia (sexual state) and Leptodothiorella (spermatial state) (Glienke et al. 2011;Wikee et al. 2011). ...
Phyllosticta (Phyllostictaceae, Botryosphaeriales) includes plant pathogens, endophytes and saprobes, occurring on various hosts worldwide. During the present study, isolates associated with leaf spots were obtained from the hosts Quercus aliena and Viburnum odoratissimum, and identified based on morphological features and phylogenetic inference from the analyses of five loci (ITS, LSU, tef1, act and gapdh). Results supported the introduction of two novel species, namely Phyllosticta anhuiensis and P. guangdongensis. Phylogenetically, P. anhuiensis and P. guangdongensis formed two well-separated lineages in the P. concentri-ca and P. capitalensis species complexes, distinguishing from all presently accepted species in this genus by DNA sequence data. Morphologically, P. anhuiensis and P. guangdongensis have the typical structure of the genus Phyllosticta, and differed from their closely related species by the length of the conidial appendage.
... Phyllosticta contains many plant pathogenic and endophytic species, commonly occurring worldwide on a broad range of host plants (Wikee et al. 2013a). Generally, Phyllosticta species cause disease symptoms on leaves, including necrotic lesions often containing many black, globose or subglobose, and semi-immersed pycnidia (Wikee et al. 2011). In this study, disease symptoms on O. japonicus leaves and the morphological observation of pycnidia and other fungal structures on lesions showed that this disease was caused by a Phyllosticta species. ...
Ophiopogon japonicus (Asparagaceae) is a perennial grass species which can be cultivated as an ornamental and medicinal plant. From April 2021 to September 2022, a serious leaf blight disease of O. japonicus was discovered in Rizhao City, Shandong Province, China. The initial disease symptoms were small yellow spots, finally developing as tip blight, often associated with many small, black, semi-immersed pycnidial conidiomata formed in lesions. To obtain isolates of the causal agent for this disease, samples were randomly collected from O. japonicus diseased leaves in Rizhao City. In total 97 Phyllosticta isolates were obtained from samples, and studied using morphological features and multi-locus phylogenetic analyses of a combined dataset using the internal transcribed spacers (ITS), the 28S large subunit of ribosomal RNA (LSU), and partial translation elongation factor 1-alpha (tef), actin (act) and glyceraldehyde-3-phosphate dehydrogenase (gapdh) loci. Phylogenetically, these Phyllosticta isolates formed a clade in the P. concentrica species complex, and clustered with P. pilospora and P. spinarum. Morphologically, isolates in this clade differed from P. pilospora and P. spinarum by the size of conidiogenous cells and conidia, and the absence of an apical conidial appendage. As a result, these isolates were described as a novel species Phyllosticta rizhaoensis. Pathogenicity was confirmed using Koch’s postulates, which showed that P. rizhaoensis could induce leaf blight symptoms on O. japonicus in China.
... Wikee et al. [3] reinstated Phyllostictaceae as a separate family in Botryosphaeriales to accommodate Phyllosticta, which consists of Phyllosticta and Pseudofusicoccum [34]. Phyllosticta species are mostly endophytes, but several are plant pathogens that cause leaf spots in a broad range of hosts worldwide [38][39][40][41][42]. Barr [43] introduced Planistromellaceae, which currently comprises two genera, namely, Kellermania and Umthunziomyces [33]. ...
Botryosphaeriales (Dothideomycetes, Ascomycota) occur in a wide range of habitats as endo-phytes, saprobes, and pathogens. The order Botryosphaeriales has not been subjected to evaluation since 2019 by Phillips and co-authors using phylogenetic and evolutionary analyses. Subsequently, many studies introduced novel taxa into the order and revised several families separately. In addition , no ancestral character studies have been conducted for this order. Therefore, in this study, we re-evaluated the character evolution and taxonomic placements of Botryosphaeriales species based on ancestral character evolution, divergence time estimation, and phylogenetic relationships, including all the novel taxa that have been introduced so far. Maximum likelihood, maximum parsimony, and Bayesian inference analyses were conducted on a combined LSU and ITS sequence alignment. Ancestral state reconstruction was carried out for conidial colour, septation, and nutritional mode. Divergence times estimates revealed that Botryosphaeriales originated around 109 Mya in the early epoch of the Cretaceous period. All six families in Botryosphaeriales evolved in the late epoch of the Cretaceous period (66-100 Mya), during which Angiosperms also appeared, rapidly diversified and became dominant on land. Families of Botryosphaeriales diversified during the Paleogene and Neogene periods in the Cenozoic era. The order comprises the families Aplosporellaceae, Botryosphaeriaceae, Melanopsaceae, Phyllostictaceae, Planistromellaceae and Saccharataceae. Furthermore, current study assessed two hypotheses; the first one being "All Botryosphaeriales species originated as endophytes and then switched into saprobes when their hosts died or into pathogens when their hosts were under stress"; the second hypothesis states that "There is a link between the conidial colour and nutritional mode in botryosphaerialean taxa". Ancestral state reconstruction and nutritional mode analyses revealed a pathogenic/saprobic nutritional mode as the ancestral character. However, we could not provide strong evidence for the first hypothesis mainly due to the significantly low number of studies reporting the endophytic botryosphaerialean taxa. Results also showed that hyaline and aseptate conidia were ancestral characters in Botryosphaeriales and supported the relationship between conidial pigmentation and the pathogenicity of Botryosphaeriales species.
... Host plants include several species of the genera Vitis, Parthenocissus, Cissus and Ampelopsis [54,55] but among them, cultivars of Vitis vinifera are the most susceptible. Native American species such as fox grape (Vitis labrusca), muscadine (Vitis rotundifolia) and Arizona grape (Vitis arizonica) are also susceptible. ...
... P. capitalensis is indeed isolated worldwide as an endophyte, although it was originally described by Hennings [145] as a fungal pathogen of Stanhopea (Orchidaceae) in Brazil, and is now considered in the scientific literature not only as an endophyte but also as a plant pathogen of minor importance [55,138]. Furthermore, the concept of "endophytic fungi" is not consistently used in the scientific literature and this is likely to be the case for P. capitalensis. ...
The aim of this review is to provide readers with an integrated knowledge on black rot of grapes, based on a critical survey of previous and recent studies of scientific importance. The current state of the art and perspectives of science are presented, not only on the genetic determinants of grapevine resistance to black rot, predictive models of black rot epidemics, but also on the potential of metabolomics to explore black rot-grape interactions and shorten plant breeding processes. Numerous complications of disease management and ambiguities in phenotype-classification are highlighted, and by exploring the limitations and inconsistencies of previous studies, insights into key dilemmas and controversial findings are also provided, suggesting future research directions. Much research has been conducted, but biochemical and molecular studies of the true interactions between grapevine and Guignardia bidwellii are still rarity.
... A similar situation is also present in filamentous organisms not belonging to Fungi, e.g. in the oomycete genus Bremia (Choi and Thines 2015), highlighting parallel evolution in filamentous organisms. There are several other well-known and important species of phytopathogenic fungi that represent complexes of cryptic species, such as Calonectria (Lombard et al. 2010), Cercospora (Groenewald et al. 2005;Crous et al. 2006a), Fusarium (Aoki et al. 2005Summerell et al. 2010Summerell et al. , 2011, Cladosporium (Bensch et al. 2012), Colletotrichum (Crouch et al. 2009;Phoulivong et al. 2010;Damm et al. 2012a,b), Harknessia , Ilyonectria (Cabral et al. 2012a,b) and Phyllosticta (Glienke et al. 2011;Wikee et al. 2011;Wang et al. 2012). ...
... Following spore germination, if compatible mycelia come into contact, they will undergo sexual reproduction (Tran et al. 2017(Tran et al. , 2020Wang et al. 2016). Additionally, P. citricarpa produces spermatia ( Supplementary Fig. S1), structures that act as gametes but do not contribute directly to dispersal and infection (Higgins 1929;Tran et al. 2017;Wikee et al. 2011). ...
... Phyllosticta citricarpa is reported to have a lower genetic diversity than other non-pathogenic Phyllosticta species (Baldassari et al., 2008;Miles et al., 2013). This is likely due to host specialisation of P. citricarpa limited to Citrus, in contrast to the broader host range of, for example, the endophyte P. capitalensis (Miles et al., 2013;Wikee et al., 2011;Wikee et al., 2013). Comparative genome analysis of pathogenic Phyllosticta species, P. citricarpa, and P. citriasiana with those of the endophytic P. capitalensis, revealed genomic differences and genes that might be essential factors for host specialization and could explain the different lifestyles of these fungi (Rodrigues et al., 2019;Wang et al., 2020). ...
Phyllosticta citricarpa is a fungal pathogen causing citrus black spot (CBS). As a regulated pest in some countries, the presence of the pathogen limits the export of fruit and is therefore of agricultural and economic importance. In this study, we used high throughput sequencing data to infer the global phylogeographic distribution of this pathogen, including 71 isolates from eight countries, Argentina, Australia, Brazil, China, Cuba, Eswatini, South Africa and the United States of America.
We assembled draft genomes and used a pairwise read mapping approach for the detection and enumeration of variants between isolates. We performed SSR marker discovery based on the assembled genome with the best assembly statistics, and generated genotype profiles for all isolates with 1,987 SSR markers in silico. Furthermore, we identified 32,560 SNPs relative to a reference sequence followed by population genetic analyses based on the three datasets; pairwise variant counts, SSR genotypes and SNP genotypes. All three analysis approaches gave similar overall results. Possible pathways of dissemination among the populations from China, Australia, southern Africa and the Americas are postulated. The Chinese population is the most diverse, and is genetically the furthest removed from all other populations, and is therefore considered the closest to the origin of the pathogen. Isolates from Australia, Eswatini and the South African province Mpumalanga are closely associated and clustered together with those from Argentina and Brazil. The Eastern Cape, North West, and KwaZulu-Natal populations in South Africa grouped in another cluster, while isolates from Limpopo are distributed between the two aforementioned clusters. Southern African populations showed a close relationship to populations in North America, and could be a possible source of P. citricarpa populations that are now found in North America.
This study represents the largest whole genome sequencing survey of P. citricarpa to date and provides a more comprehensive assessment of the population genetic diversity and connectivity of P. citricarpa from different geographic origins. This information could further assist in a better understanding of the epidemiology of the CBS pathogen, its long-distance dispersal and dissemination pathways, and can be used to refine phytosanitary regulations and management programmes for the disease.
