Leaf Blight of Buxus sempervirens in Northern Forests of Iran Caused by Calonectria pseudonaviculata

Buxus sempervirens subsp. hyrcana (Pojark.) Takht. (boxwood) is an evergreen shrub/tree in Caspian hyrcanian forests covering the Alborz mountain range of northern Iran. During the summer of 2012, a sudden leaf and twig blight disease of boxwood was observed throughout the northern forests of Iran. Disease symptoms included circular dark spots on leaves leading to defoliation, and longitudinal brown-black streaks on the shoots. Diseased plant material was collected from the Guilan and Mazandaran areas, placed in moist chambers, and incubated at 20°C to induce sporulation. Single conidia were plated onto half-strength potato dextrose agar supplemented with 250 mg/L streptomycin and incubated at 25°C under near-ultraviolet light. Isolates were transferred to carnation leaf agar and incubated at 25°C under near-ultraviolet for morphological characterization, and representative isolates were deposited into the culture collection of the CBS-KNAW Fungal Biodiversity Centre under accession numbers CBS 134431 and CBS 134432. Gross morphological characters were determined by mounting fungal structures in lactic acid and 50 measurements at 1,000× magnification were made for all taxonomically informative characters. The observed macroconidiophores consisted of a stipe bearing a penicillate suite of reproductive branches and a stipe extension, terminating in a naviculate vesicle. The stipe extensions were septate, hyaline (85 to 160 × 2 to 4 μm), terminating in a naviculate vesicle, 6 to 11 μm in diam. Conidia were cylindrical, rounded at both ends, straight, with one septum (55 to 68 × 4 to 6 μm). These morphological observations agreed to those provided for C. pseudonaviculata Lombard, M. J. Wingf. & Crous (1,2). To confirm morphological identification, DNA sequence data were generated for the ITS1-5.8S-ITS2 region of the rDNA, and a fragment of the translation elongation factor 1-alpha gene region (3). These sequences were compared to other sequences of C. pseudonaviculata in GenBank (100% similarity for both loci), which confirmed the morphological observations. Sequences were submitted to GenBank under the accession numbers KC736850 and KC736851 for ITS, and KC736852 and KC736853 for TEF. Koch's postulates were proven by spraying a 3 × 106 conidia/ml conidial suspension of isolate CBS 134431 onto 1-year-old B. sempervirens subsp. hyrcana plants until run-off, and covering them for 24 h with a plastic bag to maintain high humidity. Control plants were sprayed with sterile water. Ten plants were used for each treatment and maintained in a greenhouse at 20 to 22°C with 95% relative humidity. Symptoms similar to those observed in nature developed within 4 days of inoculation and the test fungus was successfully reisolated from the inoculated plants. No symptoms were observed on the control plants. Boxwood blight caused by C. pseudonaviculata, was first reported in the United Kingdom in the mid-1990s and has since become widespread, causing epidemics globally (1,2,4). To our knowledge, this study represents the first report of boxwood blight in its native environment and in Iran. References: (1) P. W. Crous et al. Sydowia 54:23, 2002. (2) B. Henricot and A. Culham. Mycologia 94:980, 2002. (3) L. Lombard et al. Stud. Mycol. 66:31, 2010. (4) M. R. Saracchi et al. J. Plant Pathol. 90:581, 2009.

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ITS sequence data and morphology differentiate Cytospora chrysosperma associated with trunk disease of grapevine in northern Iran

Journal of Plant Protection Research ◽

10.1515/jppr-2015-0015 ◽

2015 ◽

Vol 55 (2) ◽

pp. 117-125 ◽

Cited By ~ 6

Author(s):

Mahdi Arzanlou ◽

Abolfazl Narmani

Keyword(s):

Economic Impact ◽

Sequence Data ◽

Morphological Identification ◽

Its Sequence ◽

Northern Iran ◽

Grapevine Trunk Diseases ◽

Cytospora Chrysosperma ◽

Trunk Diseases ◽

Woody Host ◽

Pathogenicity Assay

Abstract Trunk diseases are potential threats for the grapevine industry owing to the worldwide incidence and economic impact of the diseases. Several fungal groups are known to be involved in these diseases. In a survey on grapevine trunk diseases in northern Iran, Cytospora isolates were repeatedly recovered from vines showing decline symptoms. The symptoms appeared as pale brown to brown streaks in longitudinal cuts of shoots. The morphological and cultural characteristics of the isolates were in agreement with the description of Cytospora chrysosperma. Sequence data of the ITS-rDNA region was used to further confirm the identity of the species. Phylogenetic analysis based on the sequence data obtained in this study and the sequences from GenBank, confirmed the morphological identification. Our isolates were clustered together with C. chrysosperma isolates known from other woody host plant species. The pathogenicity assay on detached shoots of grapevines induced the same symptoms as was observed in field conditions. Although, C. chrysosperma is known from several woody hosts in Iran, the occurrence of this species on grapevines showing decline symptoms is new. The economic impact, distribution, and degree of involvement of C. chrysosperma in decline of vines in other regions of Iran remains to be studied.

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Morphometric, genetic diversity and phylogenetic analysis of Taenia hydatigena (Pallas, 1766) larval stage in Iranian livestock

Parasitology ◽

10.1017/s0031182019001434 ◽

2019 ◽

Vol 147 (2) ◽

pp. 231-239

Author(s):

Shahabeddin Sarvi ◽

Laya Ebrahimi Behrestaghi ◽

Abbas Alizadeh ◽

Seyed Abdollah Hosseini ◽

Shaban Gohardieh ◽

...

Keyword(s):

Genetic Diversity ◽

Larval Stage ◽

Sequence Data ◽

Genetic Difference ◽

12S Rrna ◽

Northern Iran ◽

Taenia Hydatigena ◽

Cysticercus Tenuicollis ◽

Significant Difference ◽

Cox 1

AbstractCysticercus tenuicollis as metacestode of Taenia hydatigena is the most prevalent taeniid species in livestock. Eighty-eight C. tenuicollis samples were collected from sheep (n = 44) and goats (n = 44) of the northern Iran from 2015 to 2016. The isolated parasites were characterized by morphometric keys. The DNA of the larval stage was extracted, amplified and sequenced targeting mitochondrial 12S rRNA and Cox 1 markers. A significant difference in larval rostellar hook length was observed in 12S rRNA haplotypes. Analysis of molecular variance of 12S rRNA indicated a moderate genetic diversity in the C. tenuicollis isolates. The pairwise sequence distance of C. tenuicollis showed an intra-species diversity of 0.3–0.5% and identity of 99.5–100%. Using the 12S rRNA sequence data we found a moderate genetic difference (Fst; 0.05421) in C. tenucollis isolates collected from livestock of the northern and southeastern regions of Iran. We concluded that the genetic variants of C. tenuicollis are being undoubtedly distributing mostly in different parts of Iran. Further studies with a larger number of T. hydatigena isolates collected from various intermediate and definitive hosts are needed to study this evolutionary assumption and also to determine the apparent genetic differences observed in the studied regions.

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First Report of a Leaf Spot Disease of Bells-of-Ireland (Moluccella laevis) Caused by Cercospora apii in California

Plant Disease ◽

10.1094/pdis.2003.87.2.203a ◽

2003 ◽

Vol 87 (2) ◽

pp. 203-203

Author(s):

S. T. Koike ◽

S. A. Tjosvold ◽

J. Z. Groenewald ◽

P. W. Crous

Keyword(s):

Leaf Spot ◽

Sequence Data ◽

Disease Incidence ◽

Leaf Spot Disease ◽

Conidial Suspension ◽

Internal Transcribed Spacer Region ◽

First Report ◽

Spot Disease ◽

Leaf Spots ◽

Initial Symptoms

Bells-of-Ireland (Moluccella laevis) (Lamiaceae) is an annual plant that is field planted in coastal California (Santa Cruz County) for commercial cutflower production. In 2001, a new leaf spot disease was found in these commercially grown cutflowers. The disease was most serious in the winter-grown crops in 2001 and 2002, with a few plantings having as much as 100% disease incidence. All other plantings that were surveyed during this time had at least 50% disease. Initial symptoms consisted of gray-green leaf spots. Spots were generally oval in shape, often delimited by the major leaf veins, and later turned tan. Lesions were apparent on both adaxial and abaxial sides of the leaves. A cercosporoid fungus having fasciculate conidiophores, which formed primarily on the abaxial leaf surface, was consistently associated with the spots. Based on morphology and its host, this fungus was initially considered to be Cercospora molucellae Bremer & Petr., which was previously reported on leaves of M. laevis in Turkey (1). However, sequence data obtained from the internal transcribed spacer region (ITS1, ITS2) and the 5.8S gene (STE-U 5110, 5111; GenBank Accession Nos. AY156918 and AY156919) indicated there were no base pair differences between the bells-of-Ireland isolates from California, our own reference isolates of C. apii, as well as GenBank sequences deposited as C. apii. Based on these data, the fungus was subsequently identified as C. apii sensu lato. Pathogenicity was confirmed by spraying a conidial suspension (1.0 × 105 conidia/ml) on leaves of potted bells-of-Ireland plants, incubating the plants in a dew chamber for 24 h, and maintaining them in a greenhouse (23 to 25°C). After 2 weeks, all inoculated plants developed leaf spots that were identical to those observed in the field. C. apii was again associated with all leaf spots. Control plants, which were treated with water, did not develop any symptoms. The test was repeated and the results were similar. To our knowledge this is the first report of C. apii as a pathogen of bells-of-Ireland in California. Reference: (1) C. Chupp. A Monograph of the Fungus Genus Cercospora. Cornell University Press, Ithaca, New York, 1954.

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First Report of Leaf Spot of Rudbeckia hirta var. pulcherrima Caused by Septoria rudbeckiae in Korea

Plant Disease ◽

10.1094/pdis-02-12-0172-pdn ◽

2012 ◽

Vol 96 (6) ◽

pp. 911-911 ◽

Cited By ~ 1

Author(s):

J. H. Park ◽

S. E. Cho ◽

K. S. Han ◽

H. D. Shin

Keyword(s):

Leaf Spot ◽

The United States ◽

Flowering Plant ◽

Leaf Spot Disease ◽

Morphological Identification ◽

Its Sequence ◽

Conidial Suspension ◽

First Report ◽

Rudbeckia Hirta ◽

Close Phylogenetic Relationship

Rudbeckia hirta L. var. pulcherrima Farw. (synonym R. bicolor Nutt.), known as the black-eyed Susan, is a flowering plant belonging to the family Asteraceae. The plant is native to North America and was introduced to Korea for ornamental purposes in the 1950s. In July 2011, a previously unknown leaf spot was first observed on the plants in a public garden in Namyangju, Korea. Leaf spot symptoms developed from lower leaves as small, blackish brown lesions, which enlarged to 6 mm in diameter. In the later stages of disease development, each lesion was usually surrounded with a yellow halo, detracting from the beauty of the green leaves of the plant. A number of black pycnidia were present in diseased leaf tissue. Later, the disease was observed in several locations in Korea, including Pyeongchang, Hoengseong, and Yangpyeong. Voucher specimens were deposited at the Korea University Herbarium (KUS-F25894 and KUS-F26180). An isolate was obtained from KUS-F26180 and deposited at the Korean Agricultural Culture Collection (Accession No. KACC46694). Pycnidia were amphigenous, but mostly hypogenous, scattered, dark brown-to-rusty brown, globose, embedded in host tissue or partly erumpent, 50 to 80 μm in diameter, with ostioles 15 to 25 μm in diameter. Conidia were substraight to mildly curved, guttulate, hyaline, 25 to 50 × 1.5 to 2.5 μm, and one- to three-septate. Based on the morphological characteristics, the fungus was consistent with Septoria rudbeckiae Ellis & Halst. (1,3,4). Morphological identification of the fungus was confirmed by molecular data. Genomic DNA was extracted using the DNeasy Plant Mini DNA Extraction Kit (Qiagen Inc., Valencia, CA.). The internal transcribed spacer (ITS) region of rDNA was amplified using the ITS1/ITS4 primers and sequenced. The resulting sequence of 528 bp was deposited in GenBank (Accession No. JQ677043). A BLAST search showed that there was no matching sequence of S. rudbeckiae; therefore, this is the first ITS sequence of the species submitted to GenBank. The ITS sequence showed >99% similarity with those of many Septoria species, indicating their close phylogenetic relationship. Pathogenicity was tested by spraying leaves of three potted young plants with a conidial suspension (2 × 105 conidia/ml), which was harvested from a 4-week-old culture on potato dextrose agar. Control leaves were sprayed with sterile water. The plants were covered with plastic bags to maintain 100% relative humidity (RH) for the first 24 h. Plants were then maintained in a greenhouse (22 to 28°C and 70 to 80% RH). After 5 days, leaf spot symptoms identical to those observed in the field started to develop on the leaves inoculated with the fungus. No symptoms were observed on control plants. S. rudbeckiae was reisolated from the lesions of inoculated plants, confirming Koch's postulates. A leaf spot disease associated with S. rudbeckiae has been reported on several species of Rudbeckia in the United States, Romania, and Bulgaria (1–4). To our knowledge, this is the first report of leaf spot on R. hirta var. pulcherrima caused by S. rudbeckiae in Korea. References: (1) J. B. Ellis and B. D. Halsted. J. Mycol. 6:33, 1890. (2) D. F. Farr and A. Y. Rossman. Fungal Databases. Systematic Mycology and Microbiology Laboratory, ARS, USDA. Retrieved from http://nt.ars-grin.gov/fungaldatabases/ February 2, 2012. (3) E. Radulescu et al. Septoriozele din Romania. Ed. Acad. Rep. Soc. Romania, Bucuresti, Romania, 1973. (4) S. G. Vanev et al. Fungi Bulgaricae 3:1, 1997.

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First Report of Curvularia aeria on Etlingera linguiformis from Nagaland, India

Plant Disease ◽

10.1094/pdis-01-14-0060-pdn ◽

2014 ◽

Vol 98 (11) ◽

pp. 1580-1580 ◽

Cited By ~ 2

Author(s):

C. Kithan ◽

L. Daiho

Keyword(s):

Leaf Surface ◽

Agricultural Research ◽

Disease Incidence ◽

Indian Agricultural Research Institute ◽

Mountain Range ◽

Pathogenicity Test ◽

Distilled Water ◽

Conidial Suspension ◽

First Report ◽

Initial Symptoms

Etlingera linguiformis (Roxb.) R.M.Sm. of Zingiberaceae family is an important indigenous medicinal and aromatic plant of Nagaland, India, that grows well in warm climates with loamy soil rich in humus (1). The plant rhizome has medicinal benefits in treating sore throats, stomachache, rheumatism, and respiratory complaints, while its essential oil is used in perfumery. A severe disease incidence of leaf blight was observed on the foliar portion of E. linguiformis at the Patkai mountain range of northeast India in September 2012. Initial symptoms of the disease are small brown water soaked flecks appearing on the upper leaf surface with diameter ranging from 0.5 to 3 cm, which later coalesced to form dark brown lesions with a well-defined border. Lesions often merged to form large necrotic areas, covering more than 90% of the leaf surface, which contributed to plant death. The disease significantly reduces the number of functional leaves. As disease progresses, stems and rhizomes were also affected, reducing quality and yield. The diseased leaf tissues were surface sterilized with 0.2% sodium hypochlorite for 2 min followed by rinsing in sterile distilled water and transferred into potato dextrose agar (PDA) medium. After 3 days, the growing tips of the mycelium were transferred to PDA slants and incubated at 25 ± 2°C until conidia formation. Fungal colonies on PDA were dark gray to dark brown, usually zonate; stromata regularly and abundantly formed in culture. Conidia were straight to curved, ellipsoidal, 3-septate, rarely 4-septate, middle cells broad and darker than other two end cells, middle septum not median, smooth, 18 to 32 × 8 to 16 μm (mean 25.15 × 12.10 μm). Conidiophores were terminal and lateral on hyphae and stromata, simple or branched, straight or flexuous, often geniculate, septate, pale brown to brown, smooth, and up to 800 μm thick (2,3). Pathogen identification was performed by the Indian Type Culture Collection, Division of Plant Pathology, Indian Agricultural Research Institute, New Delhi (ITCC Accession No. 7895.10). Further molecular identity of the pathogen was confirmed as Curvularia aeria by PCR amplification and sequencing of the internal transcribed spacer (ITS) regions of the ribosomal DNA by using primers ITS4 and ITS5 (4). The sequence was submitted to GenBank (Accession No. MTCC11875). BLAST analysis of the fungal sequence showed 100% nucleotide similarity with Cochliobolus lunatus and Curvularia aeria. Pathogenicity tests were performed by spraying with an aqueous conidial suspension (1 × 106 conidia /ml) on leaves of three healthy Etlingera plants. Three plants sprayed with sterile distilled water served as controls. The first foliar lesions developed on leaves 7 days after inoculation and after 10 to 12 days, 80% of the leaves were severely infected. Control plants remained healthy. The inoculated leaves developed similar blight symptoms to those observed on naturally infected leaves. C. aeria was re-isolated from the inoculated leaves, thus fulfilling Koch's postulates. The pathogenicity test was repeated twice. To our knowledge, this is the first report of the presence of C. aeria on E. linguiformis. References: (1) M. H. Arafat et al. Pharm. J. 16:33, 2013. (2) M. B. Ellis. Dematiaceous Hyphomycetes. CMI, Kew, Surrey, UK, 1971. (3) K. J. Martin and P. T. Rygiewicz. BMC Microbiol. 5:28, 2005. (4) C. V. Suberamanian. Proc. Indian Acad. Sci. 38:27, 1955.

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First Report of Brown Rot Caused by Monilinia fructicola Affecting Peach Orchards in Slovenia

Plant Disease ◽

10.1094/pdis-94-9-1166a ◽

2010 ◽

Vol 94 (9) ◽

pp. 1166-1166 ◽

Cited By ~ 15

Author(s):

A. Munda ◽

M. Viršček Marn

Keyword(s):

Prunus Persica ◽

Brown Rot ◽

Fruit Rot ◽

Morphological Identification ◽

Monilinia Fructicola ◽

Conidial Suspension ◽

Stone Fruits ◽

The European Union ◽

First Report ◽

Representative Isolate

Monilinia fructicola, the causal agent of brown rot, is a destructive fungal pathogen that affects mainly stone fruits (Prunoideae). It causes fruit rot, blossom wilt, twig blight, and canker formation and is common in North and South America, Australia, and New Zealand. M. fructicola is listed as a quarantine pathogen in the European Union and was absent from this region until 2001 when it was detected in France. In August 2009, mature peaches (Prunus persica cv. Royal Glory) with brown rot were found in a 5-year-old orchard in Goriška, western Slovenia. Symptoms included fruit lesions and mummified fruits. Lesions were brown, round, rapidly extending, and covered with abundant gray-to-buff conidial tufts. The pathogen was isolated in pure culture and identified based on morphological and molecular characters. Colonies on potato dextrose agar (PDA) incubated at 25°C in darkness had an average daily growth rate of 7.7 mm. They were initially colorless and later they were light gray with black stromatal plates and dense, hazel sporogenous mycelium. Colony margins were even. Sporulation was abundant and usually developed in distinct concentric zones. Limoniform conidia, produced in branched chains, measured 10.1 to 17.7 μm (mean = 12.1 μm) × 6.2 to 8.6 μm (mean = 7.3 μm) on PDA. Germinating conidia produced single germ tubes whose mean length ranged from 251 to 415 μm. Microconidia were abundant, globose, and 3 μm in diameter. Morphological characters resembled those described for M. fructicola (1). Morphological identification was confirmed by amplifying genomic DNA of isolates with M. fructicola species-specific primers (2–4). Sequence of the internal transcribed spacer (ITS) region (spanning ITS1 and ITS 2 plus 5.8 rDNA) of a representative isolate was generated using primers ITS1 and ITS4 and deposited in GenBank (Accession No. GU967379). BLAST analysis of the 516-bp PCR product revealed 100% identity with several sequences deposited for M. fructicola in NCBI GenBank. Pathogenicity was tested by inoculating five mature surface-sterilized peaches with 10 μl of a conidial suspension (104 conidia ml–1) obtained from one representative isolate. Sterile distilled water was used as a control. Peaches were wounded prior to inoculation. After 5 days of incubation at room temperature and 100% relative humidity, typical brown rot symptoms developed around the inoculation point, while controls showed no symptoms. M. fructicola was reisolated from lesion margins. Peach and nectarine orchards in a 5-km radius from the outbreak site were surveyed in September 2009 and M. fructicola was confirmed on mummified fruits from seven orchards. The pathogen was not detected in orchards from other regions of the country, where only the two endemic species M. laxa and M. fructigena were present. To our knowledge, this is the first report of M. fructicola associated with brown rot of stone fruits in Slovenia. References: (1) L. R. Batra. Page 106 in: World Species of Monilinia (Fungi): Their Ecology, Biosystematics and Control. J. Cramer, Berlin, 1991. (2) M.-J. Côté et al. Plant Dis. 88:1219, 2004. (3) K. J. D. Hughes et al. EPPO Bull. 30:507, 2000. (4) R. Ioos and P. Frey. Eur. J. Plant Pathol. 106:373, 2000.

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Pyrenochaetopsis kuksensis (Pyrenochaetopsidaceae), a new species associated with an ornamental boxwood in the Czech Republic

Phytotaxa ◽

10.11646/phytotaxa.498.3.3 ◽

2021 ◽

Vol 498 (3) ◽

pp. 177-185

Author(s):

MILAN ŠPETÍK ◽

AKILA BERRAF-TEBBAL ◽

ROBERT POKLUDA ◽

ALEŠ EICHMEIER

Keyword(s):

Czech Republic ◽

New Species ◽

Phylogenetic Relationships ◽

Sequence Data ◽

Phylogenetic Analyses ◽

New Taxon ◽

The Czech Republic ◽

Buxus Sempervirens ◽

Fungal Microbiome ◽

A New Species

During the investigation of fungal microbiome associated with boxwood in the Czech Republic, samples from Buxus sempervirens L. (Buxaceae) plants were collected and used for isolation. Two fungal strains were proposed as a new species Pyrenochaetopsis kuksensis based on morphology as well as phylogenetic analyses of ITS, LSU, rpb2, and tub2 sequence data. Detailed descriptions and phylogenetic relationships of the new taxon are provided.

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Paradiplozoon vaalense n. sp. (Monogenea: Diplozoidae) from the gills of moggel, Labeo umbratus (Smith, 1841), in the Vaal River System, South Africa

Journal of Helminthology ◽

10.1017/s0022149x1300059x ◽

2013 ◽

Vol 89 (1) ◽

pp. 58-67 ◽

Cited By ~ 16

Author(s):

Q.M. Dos Santos ◽

B. Jansen van Vuuren ◽

A. Avenant-Oldewage

Keyword(s):

South Africa ◽

Sequence Data ◽

Light And Electron Microscopy ◽

River System ◽

Ribosomal Gene ◽

Its2 Region ◽

Genetic Characteristics ◽

Vaal River ◽

Vaal Dam ◽

Second Internal Transcribed Spacer

AbstractAn unidentified monogenean diplozoid species was collected from the gills of moggel in the Vaal River and Vaal Dam, South Africa. Specimens were removed from gills of the hosts and observed using light and electron microscopy to compare these diplozoids with known species. The second internal transcribed spacer (ITS2) of the ribosomal gene was amplified, sequenced and compared to that of other diplozoid taxa. Morphological species delimitation was used to determine the identity of these diplozoids, but they did not match the description of any diplozoid taxa. This species is recognized by the specific size of the hooks, number of plicae in posterior and trapezoid anterior projection of the median sclerite connecting to the clamp jaws via a single sclerite, occasionally with two small additional sclerites. Genetic characteristics based on sequence data from the ITS2 region also distinguish this taxon from all other diplozoid taxa. This South African diplozoid grouped in the same clade as Paradiplozoon ichthyoxanthon Avenant-Oldewage, 2013. Data clearly indicate that diplozoids collected from moggel represent a new, distinct taxon of Paradiplozoon Akhmerov, 1974 and are described here as Paradiplozoon vaalense n. sp.

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Multi-gene incongruence consistent with hybridisation in Cladocopium (Symbiodiniaceae), an ecologically important genus of coral reef symbionts

10.7287/peerj.preprints.27614 ◽

2019 ◽

Author(s):

Joshua I Brian ◽

Simon K Davy ◽

Shaun P Wilkinson

Keyword(s):

Sequence Data ◽

Incomplete Lineage Sorting ◽

Reticulate Evolution ◽

Next Generation Sequencing Data ◽

Putative Hybrid ◽

Its2 Region ◽

Sequencing Data ◽

Lineage Sorting ◽

Evolutionary Potential ◽

Unbiased Test

Coral reefs rely on their intracellular dinoflagellate symbionts (family Symbiodiniaceae) for nutritional provision in nutrient-poor waters, yet this association is threatened by thermally stressful conditions. Despite this, the evolutionary potential of these symbionts remains poorly characterised. In this study, we tested the potential for divergent Symbiodiniaceae types to sexually reproduce (i.e. hybridise) within Cladocopium, the most ecologically prevalent genus in this family. With sequence data from three organelles (cob gene, mitochondria; psbAncr region, chloroplast; and ITS2 region, nucleus), we utilised the Incongruence Length Difference test, Approximately Unbiased test, tree hybridisation analyses and visual inspection of raw data in stepwise fashion to highlight incongruences between organelles, and thus provide evidence of reticulate evolution. Using this approach, we identified three putative hybrid Cladocopium samples among the 158 analysed, at two of the seven sites sampled. These samples were identified as the common Cladocopium types C40 or C1 with respect to the mitochondria and chloroplasts, but the rarer types C3z, C3u and C1# with respect to their nuclear identity. These five Cladocopium types have previously been confirmed as evolutionarily distinct and were also recovered in non-incongruent samples multiple times, which is strongly suggestive that they sexually reproduced to produce the incongruent samples. A concomitant inspection of Next Generation Sequencing data for these samples suggests that other plausible explanations, such as incomplete lineage sorting, are much less likely. The approach taken in this study allows incongruences between gene regions to be identified with confidence, and brings new light to the evolutionary potential within Symbiodiniaceae.

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Akanthomyces neocoleopterorum, a new verticillium-like species

Phytotaxa ◽

10.11646/phytotaxa.432.2.2 ◽

2020 ◽

Vol 432 (2) ◽

pp. 119-124

Author(s):

WAN-HAO CHEN ◽

YAN-FENG HAN ◽

JIAN-DONG LIANG ◽

ZONG-QI LIANG

Keyword(s):

Phylogenetic Analysis ◽

New Species ◽

Sequence Data ◽

Morphological Identification ◽

Data Support ◽

Extant Species ◽

A New Species

A new species, Akanthomyces neocoleopterorum, which was isolated from an infected ladybug, is introduced. Morphological comparisons with extant species and DNA-based phylogenies from analysis of a multigene dataset support the establishment of the new species. It differs from other species by having mononematous and verticillium-like conidiophores, longer phialides, and mostly cylindrical conidia. Both the morphological identification and phylogenetic analysis of combined ITS, LSU, RPB1, RPB2 and TEF sequence data support A. neocoleopterorum as a new species in the genus Akanthomyces.

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