Biodiversity Data Journal :
Taxonomic Paper
|
Corresponding author: Yong Wang (yongwangbis@aliyun.com)
Academic editor: Danny Haelewaters
Received: 29 Jun 2020 | Accepted: 16 Jul 2020 | Published: 19 Aug 2020
© 2020 Subodini Wijesinghe, Yong Wang, Erio Camporesi, Dhanushka Wanasinghe, Saranyaphat Boonmee, Kevin Hyde
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation: Wijesinghe SN, Wang Y, Camporesi E, Wanasinghe DN, Boonmee S, Hyde KD (2020) A new genus of Bambusicolaceae (Pleosporales) on Corylus avellana (Fagales) from Italy. Biodiversity Data Journal 8: e55957. https://doi.org/10.3897/BDJ.8.e55957
|
In this study, we introduce Corylicola gen. nov. in the family of Bambusicolaceae (Pleosporales), to accommodate Corylicola italica sp. nov. The new species was isolated from dead branches of Corylus avellana (common hazel) in Italy. The discovery of this new genus with both sexual and asexual characters will contribute to expand the knowledge and taxonomic framework of Bambusicolaceae.
Corylicola gen. nov. has similar morphological characters compared to other genera of Bambusicolaceae. These are solitary, scattered, globose to subglobose and ostiolate ascomata; anastomosing and branching pseudoparaphyses; cylindrical asci with a well-developed ocular chamber and short furcate pedicel; and single-septate ascospores. The coelomycetous asexual morph of Corylicola has holoblastic, phialidic conidiogenous cells and light brown conidia analogous to other members in the family. Corylicola differs from the other genera of Bambusicolaceae in having yellowish-brown ascospore masses at the top of the ascomatal neck. Detailed morphological illustrations with comprehensive descriptions for the new taxa are provided, as well as a key to the genera of Bambusicolaceae. Maximum Likelihood analysis and Bayesian Inference of a combined SSU, LSU, ITS, RPB2 and TEF1 sequence dataset confirms the placement of this genus as a distinct lineage in Bambusicolaceae.
Bambusicolous fungi, Dothideomycetes, phylogeny, taxonomy
Bambusicolaceae (Pleosporales) was introduced in Dothideomycetes by
Species of Bambusicolaceae are characterised by solitary, scattered, immersed, semi-immersed to erumpent and conical or globose to subglobose ascomata; anastomosing, branching interascal filaments; cylindrical to clavate asci with a short furcate or rounded to obtuse pedicel; and slightly broad-fusiform or clavate to ellipsoidal, hyaline or yellowish to brown, single-septate ascospores with gelatinous sheath (
Bambusicola was introduced by
In this study, we introduce Corylicola gen. nov. to accommodate Corylicola italica sp. nov. isolated from Corylus avellana in Italy. We present morphological illustrations of both sexual and asexual morphs, comprehensive descriptions, phylogenetic analyses based on SSU, LSU, ITS, RPB2 and TEF1 sequence data and a key to genera in Bambusicolaceae to confirm the placement of the new genus in Bambusicolaceae.
Specimens collection, examination and isolation
Dead branches with black raised spots on the surface were collected from Corylus avellana trees in Italy (February 2019). Samples were taken to the laboratory in a plastic Ziploc bag and stored inside paper envelopes. Samples were examined and processed following the procedure described by
Single-ascospore isolation was carried out following protocols described by
DNA extraction, PCR amplification and sequencing
Genomic DNA was isolated from fruiting bodies and from scraped fresh fungal mycelium grown on PDA media for six weeks at 18°C, using the EZgeneTM Fungal gDNA extraction Kit GD2416 (Biomiga, Shanghai, China), following the manufacturer's instructions. DNA was stored at 4°C for use in regular work and at -20°C for long-term. Sequences were generated for five gene regions, small subunit (SSU), the internal transcribed spacer region (including ITS1, 5.8S, ITS2), large subunit (LSU), RNA polymerase II second largest subunit (RPB2) and translation elongation factor 1-α (TEF1). The following primers were used for PCR amplification: NS1 and NS4 for SSU, ITS5 and ITS4 for ITS, LR0R and LR5 for LSU, fRPB2-5F and fRPB2-7cR for RPB2 and EF1-983F and EF1-2218R for TEF1 (
PCR was carried out in 20 μl reactions, containing 10.0 μl of Bench TopTM Taq MasterMix PCR mixture (SinoGenoMax, Beijing, China), 1 μl of each forward and reverse primer (10 μM), 1 μl template genomic DNA and 7.0 μl deionised water. PCR protocols were as follows: For ITS and LSU: initial denaturation at 94°C for 2 mins; followed by 35 cycles of denaturation at 95°C for 30 s, annealing at 55°C for 50 s, elongation at 72°C for 90 s; and final extension at 72°C for 10 min. For SSU: initial denaturation at 95°C for 3 mins; followed by 35 cycles of denaturation at 95°C for 30 s, annealing at 55°C for 50 s, elongation at 72°C for 30 s; and final extension at 72°C for 10 min. For RPB2: initial denaturation at 94°C for 2 mins; followed by 35 cycles of denaturation at 95°C for 45 s, annealing at 57°C for 50 s, elongation at 72°C for 90 s; and final extension at 72°C for 10 min. Finally for TEF1: initial denaturation at 94°C for 2 mins; followed by 35 cycles of denaturation at 95°C for 30 s, annealing at 58°C for 50 s, elongation at 72°C for 1 min; and final extension at 72°C for 10 min. The PCR products were verified by staining with ethidium bromide on 1% agarose electrophoresis gels. Sequencing of PCR amplicons was conducted with the same primers used for PCR. Sequencing of successfully amplified PCR products was outsourced to the SinoGenoMax Sanger sequencing laboratory (Beijing, China). Lasergene SeqMan Pro v.7 software (DNASTAR, Madison, Wisconsin) was used to obtain consensus sequences from generated sequence reads. Resulting sequences were deposited in NCBI GenBank (Table
Taxa used for molecular study and their GenBank numbers.
* Newly-generated sequences are indicated by ▲ after the species name and type materials are in bold.
Abbreviation: CBS: CBS-KNAW Fungal Biodiversity Centre, Utrecht, The Netherlands; KUMCC: Kunming Institute of Botany Culture Collection, Chinese Academy of Sciences, Kunming, China; MFLU: the Herbarium of Mae Fah Luang University, Chiang Rai, Thailand; MFLUCC: Mae Fah Luang University Culture Collection, Chiang Rai, Thailand; SICAU Herbarium of Sichuan Agricultural University, Chengdu, China.
Species |
Strain /Voucher |
SSU |
LSU |
ITS |
TEF1 |
RPB2 |
Bambusicola bambusae |
MFLUCC 11-0614 |
JX442039 | JX442031 | |||
B. didymospora |
MFLUCC 10-0557 |
KU940116 | ||||
B. didymospora |
MFLUCC 15-0189 |
|||||
B. dimorpha |
MFLUCC 13-0282 |
- |
||||
B. irregulispora |
MFLUCC 11-0437 |
JX442040 | JX442036 | |||
B. loculata |
MFLU 15-0056 |
KP761735 | KP761732 | |||
B. massarinia |
MFLUCC 11-0389 |
JX442033 | ||||
B. massarinia |
MFLUCC 11-0135 |
- |
||||
B. pustulata |
MFLUCC 15-0190 |
KU940118 | ||||
B. sichuanensis |
SICAU 16-0004 |
|||||
B. splendida |
MFLUCC 11-0611 |
- |
||||
B. splendida |
MFLUCC 11-0439 |
|||||
B. subthailandica |
SICAU 16-0005 |
|||||
B. thailandica |
MFLUCC 11-0147 |
|||||
B. triseptatispora |
MFLUCC 11-0166 |
- |
KU940120 |
- |
||
Corylicola italica▲ |
MFLUCC 20-0111 |
|||||
Corylicola italica▲ |
MFLU 19-0500 |
- |
||||
Latorua caligans |
CBS 576.65 |
- |
- |
- |
||
L. grootfonteinensis |
CBS 369.72 |
- |
KR873267 |
- |
- |
- |
Leucaenicola aseptata |
MFLUCC 17-2423 |
MK347853 | ||||
L. phraena |
MFLUCC 18-0472 |
MK347892 | MK348003 |
- |
||
Magnicamarosporium diospyricola |
MFLUCC 16-0419 |
|||||
M. iriomotense |
CBS 139696 |
- |
- |
|||
Neoaquastroma guttulatum |
MFLUCC 14-0917 |
- |
||||
Neobambusicola brunnea |
MFLU 18-1393 |
- |
- |
- |
||
N. strelitziae |
CBS 138869 |
- |
- |
|||
Palmiascoma gregariascomum |
MFLUCC 11-0175 |
KP744452 |
- |
|||
P. gregariascomum |
KUMCC 19-0201 |
- |
||||
Polyschema congolensis |
CBS 542.73 |
- |
- |
|||
P. terricola |
CBS 301.65 |
MH858576 |
- |
|||
P. larviformis |
CBS 463.88 |
- |
- |
- |
- |
|
Sulcatispora acerina |
CBS 139703 |
- |
||||
S. berchemiae |
CBS 139704 |
- |
Phylogenetic analyses
Sequences with high similarity indices were determined by BLAST searching and relevant literature (
Phylogenetic analyses of both individual and combined datasets were based on Maximum Likelihood (ML) and Bayesian Inference (BI). Both analyses were run on the CIPRES Science Gateway portal (
For BI, the sequence alignments were converted from FASTA into NEXUS format using ClustalX2 v.1.83 (
Saprobic on dead branches of Corylus avellana L. Sexual morph Ascomata solitary, scattered, immersed to erumpent, globose to subglobose, coriaceous, uni-loculate with an ostiole. Ostiole central, papillate, lined with hyaline periphyses. Peridium fused with host tissues, unequally thick, outermost layer comprising blackish to dark brown cells of textura angularis, inner layer comprising hyaline cells of textura prismatica. Hamathecium comprising numerous, dense, filamentous, cellular pseudoparaphyses with distinct septa. Asci 8-spored, bitunicate, fissitunicate, cylindrical, pedicellate, with an ocular chamber. Ascospores uniseriate, fusiform to ellipsoidal, yellowish to pale brown, single-septate, echinulate, accumulating as yellowish-brown masses at the apices of ascomatal neck. Asexual morph: Coelomycetous. Conidiomata pycnidial, solitary to gregarious, scattered, semi-immersed to superficial, globose to subglobose, uni-loculate to multi-loculate, ostiolate. Ostiolate central and circular. Conidiomata wall composed of several layers of pale to dark brown, pseudoparenchymatous cells. Conidiophores reduced to conidiogenous cells. Conidiogenous cells holoblastic, phialidic, ampulliform, yellowish to pale brown, aseptate, smooth-walled. Conidia solitary, globose or oblong to ellipsoid, rounded or obtuse ends, yellowish to pale brown, aseptate, rarely guttulate, smooth-walled.
FoF 08684
Referring to the host genus, Corylus
Corylicola gen. nov. is a monotypic genus associated with Corylus avellana L., which is commercially important for hazelnut production (
Phylogram generated from Maximum Likelihood analysis, based on combined SSU, LSU, ITS, RPB2 and TEF1 sequence data for Bambusicolaceae. Maximum Likelihood bootstrap values (ML) ≥ 70% and posterior probabilities (PP) ≥ 0.95 are given above each node. The GenBank accession numbers are provided at the right side of the species names. Strains of the novel species are visualised in blue-bold and holotype materials are symbolized with H.
Saprobic on a dead, hanging branch of Corylus avellana L. Sexual morph: (Fig.
Corylicola italica sp. nov. (MFLU 19–0500, holotype). a–b. appearance of ascomata on a twig of Corylus avellana; c. Longitudinal section of ascomata; d. ascoma neck and ascospore mass (arrowed); e peridium wall; f pseudoparaphyses; g–j. asci; k–l. ascospores; m. germinated ascospore; n–o. culture characteristics on PDA (n = from above, o = from below) Scale bars: a = 200 μm, b–c = 100 μm, d, f–j = 20 μm, e, k–m = 5 μm.
Asexual morph of Corylicola italica sp. nov. on PDA (MFLUCC 20–0111, ex-type). a. conidiomata on PDA; b. vegetative hyphae on agar media; c. longitudinal section of conidiomata; d. conidioma wall; e–h. conidiogenous cells; i–l. conidia. Scale bars: a = 200 μm, b–c = 20 μm, d = 10 μm, e–l = 5 μm.
Ascospores germinating on PDA within 24 hours from single-spore isolation. Colonies on PDA reaching 5–10 mm diam. after 14 days at 16°C, circular, crenated edge, flat with dense, whitish-grey in upper and brownish-black in the lower surface of the colony. Sporulated after 12 weeks.
FoF 08685
Referring to the country where the holotype was collected, Italy
Corylicola italica sp. nov. shows morphological characters that are similar to other representatives in the family Bambusicolaceae. Based on morphological comparison with the type species of other genera in the family, Corylicola italica is similar to Palmiascoma gregariascomum (MFLU 11–0211) in having uni-loculate ascomata, central ostioles with minute papilla, cellular pseudoparaphyses and single-septate, echinulate, brown ascospores (
The asexual state of C. italica (Fig.
Key to genera in Bambusicolaceae |
||
1 | Sexual and asexual morph known | 2 |
– | Only asexual morph known | Leucaenicola |
2 | Yellowish-brown and 1-septate ascospores | 3 |
– | Hyaline and 1–3 septate ascospores | Bambusicola |
3 | Cylindrical asci with short furcate pedicel | Corylicola |
– | Clavate asci with short rounded to obtuse pedicel | Palmiascoma |
Phylogenetic analyses
DNA sequences derived from extractions from fruiting bodies were identical to those obtained from axenic mycelium. The final concatenated SSU, ITS, LSU, RPB2 and TEF1 alignment (Fig.
In our multi-locus phylogenetic analysis (Fig.
Bamboo is a medicinal plant in which saprobic microfungi are abundant on culms and leaves (
Yong Wang would like to thank the National Natural Science Foundation of China (No. 31972222, 31560489), Program of Introducing Talents of Discipline to Universities of China (111 Program, D20023), Science and Technology basic work of MOST [2014FY120100], Talent project of Guizhou Science and Technology Cooperation Platform ([2017]5788-5 and [2019]5641) and Guizhou Science, Technology Department International Cooperation Basic project ([2018]5806). S.N. Wijesinghe would like to thank Mae Fah Luang University for financial support and S.C. Karunarathna, R.G.U. Jayalal, A.R. Rathnayaka, A.G. Niego and D. Bundhun for their precious assistance during this study. D.N. Wanasinghe would like to thank the CAS President’s International Fellowship Initiative (PIFI) for funding his postdoctoral research (number 2019PC0008), the National Science Foundation of China and the Chinese Academy of Sciences for financial support under the following grants: 41761144055, 41771063 and Y4ZK111B01. K.D. Hyde would like to thank the Thailand Research Fund (“Impact of climate change on fungal diversity and biogeography in the Greater Mekong Sub-region RDG6130001”).