Review Article |
Corresponding author: Zhuang Li ( junwuxue@126.com ) Academic editor: Huzefa Raja
© 2021 Wenxiu Sun, Shengting Huang, Jiwen Xia, Xiuguo Zhang, Zhuang Li.
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:
Sun W, Huang S, Xia J, Zhang X, Li Z (2021) Morphological and molecular identification of Diaporthe species in south-western China, with description of eight new species. MycoKeys 77: 65-95. https://doi.org/10.3897/mycokeys.77.59852
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Diaporthe species have often been reported as plant pathogens, endophytes and saprophytes, commonly isolated from a wide range of infected plant hosts. In the present study, twenty strains obtained from leaf spots of twelve host plants in Yunnan Province of China were isolated. Based on a combination of morphology, culture characteristics and multilocus sequence analysis of the rDNA internal transcribed spacer region (ITS), translation elongation factor 1-α (TEF), β-tubulin (TUB), calmodulin (CAL), and histone (HIS) genes, these strains were identified as eight new species: Diaporthe camelliae-sinensis, D. grandiflori, D. heliconiae, D. heterostemmatis, D. litchii, D. lutescens, D. melastomatis, D. pungensis and two previously described species, D. subclavata and D. tectonendophytica. This study showed high species diversity of Diaporthe in tropical rain forests and its hosts in south-western China.
Diaporthaceae, Diaporthales, phylogeny, taxonomy, 8 new taxa
Diaporthe is a genus in the Diaporthaceae family (Diaporthales), with the asexual morph previously known as Phomopsis and type species Diaporthe eres Nitschke collected from Ulmus sp. in Germany (
Currently, more than 1100 epithets of Diaporthe are listed in Index Fungorum (http://www.indexfungorum.org/; accessed 1 June 2020), but only one-fifth of these taxa have been studied with molecular data (
From previous studies, the methods of species identification and classification in genus Diaporthe were based on criteria such as morphological characters like the size and shape of ascomata (
In this study, we propose eight novel species and two previously described species of Diaporthe, collected in Yunnan Province of China on twelve plant host genera, based on their morphological characters in culture, and molecular phylogenetic analysis.
The leaves of samples were collected from Yunnan Province, China. Isolations from surface sterilized leaf tissues were conducted following the protocol of
Following 2–3 weeks of incubation, photographs of the fungal colonies were taken at 7 days and 15 days using a Powershot G7X mark II digital camera. Micromorphological characters were observed and documented in distilled water from microscope slides under Olympus SZX10 stereomicroscope and Olympus BX53 microscope, both supplied with Olympus DP80 HD color digital cameras to photo-document fungal structures. All fungal strains were stored in 10% sterilized glycerin at 4 °C for further studies. Voucher specimens were deposited in the Herbarium of Plant Pathology, Shandong Agricultural University (
Genomic DNA was extracted from fungal mycelia on PDA, using a modified cetyltrimethylammonium bromide (CTAB) protocol as described in
PCR was performed using an Eppendorf Master Thermocycler (Hamburg, Germany). Amplification reactions were performed in a 25 μL reaction volume which contained 12.5 μL Green Taq Mix (Vazyme, Nanjing, China), 1 μL of each forward and reverse primer (10 μM) (Biosune, Shanghai, China), and 1 μL template genomic DNA in amplifier, and were adjusted with distilled deionized water to a total volume of 25 μL.
PCR parameters were as follows: 95 °C for 5 min, followed by 35 cycles of denaturation at 95 °C for 30 s, annealing at a suitable temperature for 30 s, extension at 72 °C for 1 min and a final elongation step at 72 °C for 10 min. Annealing temperature for each gene was 55 °C for ITS, 60 °C for TUB, 52 °C for TEF, 54 °C for CAL and 57 °C for HIS. The PCR products were visualized on 1% agarose electrophoresis gel. Sequencing was done bi-directionally, conducted by the Biosune Company Limited (Shanghai, China). Consensus sequences were obtained using MEGA 7.0 (
Novel sequences generated from twenty strains in this study, and all reference available sequences of Diaporthe species downloaded from GenBank were used for phylogenetic analyses. Alignments of the individual locus were determined using MAFFT v. 7.110 by default settings (
Twenty fungal strains of Diaporthe isolates from 15 plant hosts were sequenced (Table
Species and GenBank accession numbers of DNA sequences used in this study with new sequences in bold.
Species | Strain/Isolate | Host/Substrate | GenBank accession number | ||||
---|---|---|---|---|---|---|---|
ITS | TUB | TEF | CAL | HIS | |||
Diaporthe alnea | CBS 146.46* | Alnus sp. | KC343008 | KC343976 | KC343734 | KC343250 | KC343492 |
D. anacardii | CBS 720.97* | Anacardium occidentale | KC343024 | KC343992 | KC343750 | KC343266 | KC343508 |
D. baccae | CBS 136972* | Vaccinium corymbosum | KJ160565 | – | KJ160597 | – | – |
D. batatas | CBS 122.21 | Ipomoea batatas | KC343040 | KC344008 | KC343766 | KC343282 | KC343524 |
D. camelliae-sinensis | SAUCC194.92* | Camellia sinensis | MT822620 | MT855817 | MT855932 | MT855699 | MT855588 |
SAUCC194.103 | Castanea mollissima | MT822631 | MT855828 | MT855943 | MT855710 | MT855599 | |
SAUCC194.104 | Castanea mollissima | MT822632 | MT855829 | MT855944 | MT855711 | MT855600 | |
SAUCC194.108 | Machilus pingii | MT822636 | MT855833 | MT855948 | MT855715 | MT855603 | |
D. canthii | CBS 132533* | Canthium inerme | JX069864 | KC843230 | KC843120 | KC843174 | – |
D. chamaeropis | CBS 753.70 | Spartium junceum | KC343049 | KC344017 | KC343775 | KC343291 | KC343533 |
D. cinerascens | CBS 719.96 | Ficus carica | KC343050 | KC344018 | KC343776 | KC343292 | KC343534 |
D. cissampeli | CPC 27302 | Cissampelos capensis | KX228273 | KX228384 | – | – | KX228366 |
D. citri | CBS 230.52 | Citrus sinensis | KC343052 | KC344020 | KC343778 | KC343294 | KC343536 |
D. collariana | MFLUCC 17-2636* | Magnolia champaca | MG806115 | MG783041 | MG783040 | MG783042 | – |
D. convolvuli | CBS 124654 | Convolvulus arvensis | KC343054 | KC344022 | KC343780 | KC343296 | KC343538 |
D. cytosporella | AR 5149 | Citrus sinensis | KC843309 | KC843223 | KC843118 | KC843143 | – |
D. destruens | SPPD-1 | Solanum tuberosum | JN848791 | JX421691 | – | – | – |
D. dorycnii | MFLU 17-1015* | Dorycnium hirsutum | KY964215 | KY964099 | KY964171 | – | – |
D. elaeagni | CBS 504.72 | Elaeagnus sp. | KC343064 | KC344032 | KC343790 | KC343306 | KC343548 |
D. elaeagni-glabrae | LC4802* | Elaeagnus glabra | KX986779 | KX999212 | KX999171 | KX999281 | KX999251 |
D. endophytica | CBS 133811* | Schinus terebinthifolius | KC343065 | KC344033 | KC343791 | KC343307 | KC343549 |
D. eres | AR5193* | Ulmus laevis | KJ210529 | KJ420799 | KJ210550 | KJ434999 | KJ420850 |
D. foeniculina | CBS 123208 | Foeniculum vulgare | KC343104 | KC344072 | KC343830 | KC343346 | KC343588 |
D. fructicola | MAFF 246408 | Passiflora edulis | LC342734 | LC342736 | LC342735 | LC342738 | LC342737 |
D. grandiflori | SAUCC194.84* | Heterostemma grandiflorum | MT822612 | MT855809 | MT855924 | MT855691 | MT855580 |
D. heliconiae | SAUCC194.75 | Heliconia metallica | MT822603 | MT855800 | MT855915 | MT855682 | MT855571 |
SAUCC194.77* | Heliconia metallica | MT822605 | MT855802 | MT855917 | MT855684 | MT855573 | |
D. heterophyllae | CPC 26215 | Acacia heterophylla | MG600222 | MG600226 | MG600224 | MG600218 | MG600220 |
D. heterostemmatis | SAUCC194.85* | Heterostemma grandiflorum | MT822613 | MT855810 | MT855925 | MT855692 | MT855581 |
SAUCC194.102 | Camellia sinensis | MT822630 | MT855827 | MT855942 | MT855709 | MT855598 | |
D. hickoriae | CBS 145.26* | Carya glabra | KC343118 | KC344086 | KC343844 | KC343360 | KC343602 |
D. inconspicua | CBS 133813* | Maytenus ilicifolia | KC343123 | KC344091 | KC343849 | KC343365 | KC343607 |
D. kongii | T12509H* | Helianthus annuus | JF431301 | KJ197272 | JN645797 | – | – |
D. litchii | SAUCC194.12 | Elaeagnus conferta | MT822540 | MT855737 | MT855854 | MT855625 | MT855509 |
SAUCC194.22* | Litchi chinensis | MT822550 | MT855747 | MT855863 | MT855635 | MT855519 | |
D. longicolla | FAU599 | Glycine max | KJ590728 | KJ610883 | KJ590767 | KJ612124 | KJ659188 |
D. lutescens | SAUCC194.36* | Chrysalidocarpus lutescens | MT822564 | MT855761 | MT855877 | MT855647 | MT855533 |
D. macintoshii | BRIP 55064a* | Rapistrum rugostrum | KJ197289 | KJ197269 | KJ197251 | – | – |
D. masirevicii | BRIP 57330 | Chrysanthemoides monilifera subsp. rotundata | KJ197275 | KJ197255 | KJ197237 | – | – |
BRIP 57892a* | Helianthus annuus | KJ197276 | KJ197257 | KJ197239 | – | – | |
D. melastomatis | SAUCC194.55* | Melastoma malabathricum | MT822583 | MT855780 | MT855896 | MT855664 | MT855551 |
SAUCC194.80 | Millettia reticulata | MT822608 | MT855805 | MT855920 | MT855687 | MT855576 | |
SAUCC194.88 | Camellia sinensis | MT822616 | MT855813 | MT855928 | MT855695 | MT855584 | |
D. melonis | CBS 507.78* | Cucumis melo | KC343142 | KC344110 | KC343868 | KC343384 | KC343626 |
D. miriciae | BRIP 54736j* | Helianthus annuus | KJ197282 | KJ197262 | KJ197244 | – | – |
D. neilliae | CBS 144.27 | Spiraea sp. | KC343144 | KC344112 | KC343870 | KC343386 | KC343628 |
D. nigra | JZBH320170 | Ballota nigra | MN653009 | MN887113 | MN892277 | – | – |
D. nomurai | CBS 157.29 | Morus sp. | KC343154 | KC344122 | KC343880 | KC343396 | KC343638 |
D. oncostoma | CBS 100454 | Robinia pseudoacacia | KC343160 | KC344128 | KC343886 | KC343402 | KC343644 |
CBS 109741 | Robinia pseudoacacia | KC343161 | KC344129 | KC343887 | KC343403 | KC343645 | |
D. ovalispora | ZJUD93* | Citrus limon | KJ490628 | KJ490449 | KJ490507 | – | KJ490570 |
D. parapterocarpi | CPC 22729 | Pterocarpus brenanii | KJ869138 | KJ869248 | – | – | – |
D. parvae | PSCG 034* | Pyrus bretschneideri | MK626919 | MK691248 | MK654858 | – | MK726210 |
D. passifloricola | CPC 27480* | Passiflora foetida | KX228292 | KX228387 | – | – | KX228367 |
D. penetriteum | LC3353* | Camellia sinensis | KP714505 | KP714529 | KP714517 | – | KP714493 |
LC3394 | Camellia sinensis | KP267893 | KP293473 | KP267967 | – | KP293544 | |
D. phaseolorum | CBS 116019 | Caperonia palustris | KC343175 | KC344143 | KC343901 | KC343417 | KC343659 |
CBS 116020 | Aster exilis | KC343176 | KC344144 | KC343902 | KC343418 | KC343660 | |
D. phillipsii | CAA 817* | Dead twig | MK792305 | MN000351 | MK828076 | MK883831 | MK871445 |
D. poincianellae | URM 7932 | Poincianella pyramidalis | MH989509 | MH989537 | MH989538 | MH989540 | MH989539 |
D. pseudoinconspicua | G26 | Poincianella pyramidalis | MH122538 | MH122524 | MH122533 | MH122528 | MH122517 |
D. psoraleae | CPC 21634 | Psoralea pinnata | KF777158 | KF777251 | KF777245 | – | – |
D. pterocarpi | MFLUCC 10-0571 | Pterocarous indicus | JQ619899 | JX275460 | JX275416 | JX197451 | – |
MFLUCC 10-0575 | Pterocarous indicus | JQ619901 | JX275462 | JX275418 | JX197453 | – | |
D. pungensis | SAUCC194.89 | Camellia sinensis | MT822617 | MT855814 | MT855929 | MT855696 | MT855585 |
SAUCC194.112* | Elaeagnus pungens | MT822640 | MT855837 | MT855952 | MT855719 | MT855607 | |
D. ravennica | MFLUCC 17-1029 | Tamarix sp. | KY964191 | KY964075 | KY964147 | – | – |
D. rosae | MFLUCC 17-2658 | Rosa sp. | MG828894 | MG843878 | – | MG829273 | – |
D. rumicicola | MFLUCC18-0739 | Rumex sp. | MH846233 | MK049555 | MK049554 | – | – |
D. saccarata | CBS 116311* | Protea repens | KC343190 | KC344158 | KC343916 | KC343432 | KC343674 |
D. shennongjiaensis | CNUCC 201905 | Juglans regia | MN216229 | MN227012 | MN224672 | MN224551 | MN224560 |
D. sojae | CBS 100.87* | Glycine soja | KC343196 | KC344164 | KC343922 | KC343438 | KC343680 |
D. stictica | CBS 370.54 | Buxus sampervirens | KC343212 | KC344180 | KC343938 | KC343454 | KC343696 |
D. subclavata | ZJUD95* | Citrus unshiu | KJ490630 | KJ490451 | KJ490509 | – | KJ490572 |
SAUCC194.66 | Pometia pinnata | MT822594 | MT855791 | MT855906 | MT855674 | MT855562 | |
D. subellipicola | KUMCC 17-0153 | on dead wood | MG746632 | MG746634 | MG746633 | – | – |
D. tectonendophytica | MFLUCC 13-0471* | Tectona grandis | KU712439 | KU743986 | KU749367 | KU749354 | – |
SAUCC194.11 | Elaeagnus conferta | MT822539 | MT855736 | MT855853 | MT855624 | MT855508 | |
SAUCC194.63 | Pometia pinnata | MT822591 | MT855788 | MT855903 | MT855672 | MT855559 | |
D. ueckerae | FAU656* | Cucumis melo | KJ590726 | KJ610881 | KJ590747 | KJ612122 | KJ659215 |
D. unshiuensis | CFCC 52595 | Carya illinoensis | MH121530 | MH121607 | MH121572 | MH121448 | MH121488 |
D. vangueriae | CPC 22703 | Vangueria infausta | KJ869137 | KJ869247 | – | – | – |
D. velutina | LC4419* | Neolitsea sp. | KX986789 | KX999222 | KX999181 | KX999286 | KX999260 |
D. virgiliae | CMW40755* | Virgilia oroboides | KP247573 | KP247582 | – | – | – |
CMW40748 | Virgilia oroboides | KP247566 | KP247575 | – | – | – | |
D. zaobaisu | PSCG 031* | Pyrus bretschneideri | MK626922 | MK691245 | MK654855 | – | MK726207 |
Diaporthella corylina | CBS 121124 | Corylus sp. | KC343004 | KC343972 | KC343730 | KC343246 | KC343488 |
ML bootstrap support values (≥ 50%) and Bayesian posterior probability (≥ 0.90) are shown as first and second position above nodes, respectively. Based on the five-locus phylogeny and morphology, 20 strains isolated in this study were assigned to 10 species, 8 of them are proposed and described here as new species (Fig.
Phylogram of Diaporthe based on combined ITS, TUB, TEF, CAL and HIS genes. The ML and BI bootstrap support values above 50% and 0.90 BYPP are shown at the first and second position, respectively. Strains marked with “*” are ex-type or ex-epitype. Strains from this study are shown in red. Three branches were shortened to fit the page size – these are indicated by symbol (//) with indication number showing how many times they are shortened.
Named after the host Camellia sinensis on which it was collected.
Diaporthe camelliae-sinensis (SAUCC194.92) a leaf of host plant b, c surface (b) and reverse (c) sides of colony after incubation for 15 days on PDA d conidiomata e–h conidiophores and conidiogenous cells i beta conidia j–l alpha conidia and beta conidia m alpha conidia. Scale bars: 10 μm (e–m).
Diaporthe camelliae-sinensis can be distinguished from the closely related species D. macintoshii R.G. Shivas et al. and D. vangueriae Crous based on ITS, TUB and TEF loci. Diaporthe camelliae-sinensis differs from D. macintoshii in smaller α-conidia and from D. vangueriae in shorter β-conidia.
China, Yunnan Province: Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, on infected leaves of Camellia sinensis. 19 April 2019, S.T. Huang, HSAUP194.92, holotype, ex-holotype living culture SAUCC194.92.
Asexual morph: Conidiomata pycnidial, multi-pycnidia grouped together, globose, black, erumpent, coated with white hyphae, thick-walled, exuding creamy to yellowish conidial droplets from central ostioles. Conidiophores hyaline, smooth, septate, branched, densely aggregated, cylindrical, straight to sinuous, swelling at the base, tapering towards the apex, 10–15 × 1.5–2 μm. Conidiogenous cells 8.5–12 × 2–2.8 μm, phialidic, cylindrical, terminal, slightly tapering towards the apex. Alpha conidia, hyaline, smooth, aseptate, ellipsoidal to fusoid, 2–4 guttulate, apex subobtuse, base subtruncate, 7.5–10 × 1.8–2.5 µm (mean = 8.5 × 2.2 μm, n = 20). Beta conidia hyaline, aseptate, filiform, sigmoid to lunate, mostly curved through 90–180°, tapering towards the apex, base truncate, 20–30 × 1.2–1.6 µm (mean = 25.6 × 1.3 μm, n = 20). Gamma conidia and sexual morph not observed.
Pure culture was isolated by subbing hyphal tips growing from surface sterilized diseased material. Colonies on PDA cover the Petri dish diameter after incubation for 15 days in dark conditions at 25 °C, cottony and radially with abundant aerial mycelium, sparse in the margin. With a tanned concentric ring of dense hyphae, white on surface side, white to pale yellow on reverse side.
China, Yunnan Province: Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, 19 April 2019, S.T. Huang. On infected leaves of Castanea mollissima, HSAUP194.103 and HSAUP194.104 paratype, living culture SAUCC194.103 and SAUCC194.104; on diseased leaves of Machilus pingii, HSAUP194.108 paratype, living culture SAUCC194.108.
Four isolates are clustered in a clade distinct from its closest phylogenetic neighbor, D. macintoshii and D. vangueriae. Diaporthe camelliae-sinensis can be distinguished from D. macintoshii in ITS, TUB and TEF loci (23/558 in ITS, 2/463 in TUB and 20/328 in TEF); from D. vangueriae in ITS and TUB loci (23/558 in ITS and 1/423 in TUB). Morphologically, Diaporthe camelliae-sinensis differs from D. macintoshii in having guttulate alpha conidia and smaller alpha conidia (7.5–10 × 1.8–2.5 vs. 8.0–11.0 × 2.0–3.0 μm) (
Named after the host Heterostemma grandiflorum on which it was collected.
Diaporthe grandiflori can be distinguished from the phylogenetically closely related species D. penetriteum Y.H. Gao & L. Cai in larger α-conidia and β-conidia.
Diaporthe grandiflori (SAUCC194.84) a leaf of Heterostemma grandiflorum b, c surface (b) and reverse (c) sides of colony after incubation for 15 days on PDA d conidiomata e conidiophores and conidiogenous cells f alpha conidia g, i alpha conidia and beta conidia h beta conidia. Scale bars: 10 μm (e–i).
China, Yunnan Province: Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, on infected leaves of Heterostemma grandiflorum. 19 April 2019, S.T. Huang, HSAUP194.84, holotype, ex-holotype living culture SAUCC194.84.
Asexual morph: Conidiomata pycnidial, subglobose to globose, solitary or aggregated in groups, black, erumpent, coated with white hyphae, thick-walled, exuding golden yellow spiral conidial cirrus from ostiole. Conidiophores hyaline, smooth, septate, branched, densely aggregated, cylindrical, straight to slightly sinuous, 9.5–16.5 × 1.9–2.8 μm. Conidiogenous cells 19.0–22.8 × 1.4–2.4 μm, cylindrical, multi-guttulate, terminal, tapering towards the apex. Alpha conidia abundant in culture, biguttulate, hyaline, smooth, aseptate, ellipsoidal, apex subobtuse, base subtruncate, 6.3–8.3 × 2.8–3.3 µm (mean = 7.5 × 2.9 μm, n = 20). Beta conidia, not numerous, hyaline, aseptate, filiform, slightly curved, tapering towards the apex, 21.5–30.5 × 1.5–2.1 µm (mean = 24.0 × 1.7 μm, n = 20). Gamma conidia not observed. Sexual morph not observed.
Pure culture was isolated by subbing hyphal tips growing from surface sterilized plant material. Colonies on PDA cover the Petri dish after 15 days kept in dark conditions at 25 °C, cottony with abundant aerial mycelium, white on surface side, white to grayish on reverse.
Phylogenetic analysis of a combined five loci showed that D. grandiflori (strain SAUCC194.84) formed an independent clade (Fig.
Named after the host Heliconia metallica on which it was collected.
Diaporthe heliconiae can be distinguished from the phylogenetically closely related species D. subclavata F. Huang, K.D. Hyde & Hong Y. Li in smaller α-conidia.
Diaporthe heliconiae (SAUCC194.77) a petiole of Heliconia metallica b, c surface (b) and reverse (c) sides of colony after incubation for 15 days on PDA d conidiomata on PDA e–g conidiophores and conidiogenous cells h beta conidia i alpha conidia and beta conidia j alpha conidia k alpha conidia and germinating conidia. All in water. Scale bars: 10 μm (e–k).
China, Yunnan Province: Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, on the symptomatic petiole of Heliconia metallica. 19 April 2019, S.T. Huang, HSAUP194.77, holotype, ex-holotype living culture SAUCC194.77.
Asexual morph: Conidiomata pycnidial, solitary or aggregated in groups, erumpent, thin-walled, superficial to embedded on PDA, dark brown to black, globose or subglobose, exuding creamy yellowish spiral conidial cirrus from the ostioles. Conidiophores hyaline, aseptate, cylindrical, straight to sinuous, branched, 16.5–25.0 × 1.3–1.8 µm. Alpha conidiogenous cells, cylindric-clavate, terminal, few guttulate, 11.5–18.0 × 1.0–1.5 µm. Beta conidiogenous cells, prismatic, terminal, few guttulate, 10.0–14.1 × 1.0–1.2 µm. Alpha conidia, hyaline, smooth, aseptate, ellipsoidal, 2–4 guttulate, apex subobtuse, base subtruncate, 5.0–6.5 × 2.0–2.5 µm (mean = 6.1 × 2.3 μm, n = 20). Beta conidia hyaline, aseptate, filiform, slightly curved, tapering towards the apex, 25.0–33.5 × 1.0–1.5 µm (mean = 29.4 × 1.3 μm, n = 20). Gamma conidia and sexual morph not observed.
Pure culture was isolated by subbing hyphal tips growing from surface sterilized infected plant material. Colonies on PDA cover the Petri dish diameter after incubation for 15 days in dark conditions at 25 °C. Aerial mycelium abundant, cottony, white, dense in the center, sparse near the margin. White on surface side, white to tanned on reverse side.
China, Yunnan Province: Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, on the symptomatic petiole of Heliconia metallica. 19 April 2019, S.T. Huang, HSAUP194.75 paratype; living culture SAUCC194.75.
Diaporthe heliconiae clade comprises strains SAUCC194.75 and SAUCC194.77, closely related to D. subclavata in the combined phylogenetic tree (Fig.
Named after the host Heterostemma grandiflorum on which it was collected.
Diaporthe heterostemmatis differs from its closest phylogenetic species D. subellipicola S.K. Huang & K.D. Hyde in ITS, TUB and TEF loci based on the alignments deposited in Tree-BASE.
Diaporthe heterostemmatis (SAUCC194.85) a leaf of host plant b, c surface (b) and reverse (c) sides of colony, after incubation for 15 days on PDA d conidiomata on PDA e, f conidiophores and conidiogenous cells g beta conidia h Alpha conidia i, j alpha conidia and beta conidia. Scale bars: 10 μm (e–j).
China, Yunnan Province: Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, on infected leaves of Heterostemma grandiflorum. 19 April 2019, S.T. Huang, HSAUP194.85, holotype, ex-holotype living culture SAUCC194.85.
Asexual morph: Conidiomata pycnidial, 3–5 pycnidia grouped together, globose, black, erumpent, exuding creamy to yellowish conidial droplets from ostioles. Conidiophores hyaline, septate, branched, elliptical or cylindrical, straight to sinuous, 6.5–10.5 × 2.5–4.5 μm. Conidiogenous cells 5.3–11.8 × 1.5–3.2 μm, phialidic, cylindrical, enlarged towards the base, tapering towards the apex, slightly curved, neck up to 5.5 μm long, 2.0 μm wide. Alpha conidia, hyaline, smooth, aseptate, ellipsoidal, biguttulate, apex subobtuse, base subtruncate, 5.8–7.5 × 2.5–3.3 µm (mean = 6.5 × 3.0 μm, n = 20). Beta conidia hyaline, aseptate, filiform, few guttulate, hooked and mostly curved through 90–180°, tapering towards both ends, 16.0–22.7 × 1.0–1.5 µm (mean = 20.4 × 1.2 μm, n = 20). Gamma conidia and sexual morph not observed.
Pure culture was isolated by subbing hyphal tips growing from surface sterilized plant material. Colonies on PDA cover the Petri dish diameter after incubation for 15 days in dark conditions at 25 °C. Aerial mycelium white, cottony, feathery, with concentric zonation, white on surface side, pale brown to black on reverse side.
China, Yunnan Province: Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, on infected leaves of Camellia sinensis. 19 April 2019, S.T. Huang, HSAUP194.102 paratype; living culture SAUCC194.102.
This new species is proposed as the molecular data showed it forms a distinct clade with high support (ML/BI=98/1) and it appears most closely related to D. subellipicola. Diaporthe heterostemmatis can be distinguished from D. subellipicola by 57 nucleotides in concatenated alignment, in which 8 were distinct in the ITS region, 28 in the TUB region and 21 in the TEF region. Morphologically, D. subellipicola was observed only on the basis of the sexual morph and culture characteristics (
Named after the host Litchi chinensis on which it was collected.
Diaporthe litchii differs from D. collariana R.H. Perrera & K.D. Hyde in smaller alpha conidia and shorter conidiophores.
China, Yunnan Province: Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, on infected leaves of Litchi chinensis. 19 April 2019, S.T. Huang, HSAUP194.22, holotype, ex-holotype living culture SAUCC194.22.
Asexual morph: Conidiomata pycnidial, 3–5 pycnidia grouped together, globose, black, erumpent, coated with white hyphae, creamy to yellowish conidial droplets exuded from central ostioles. Conidiophores hyaline, branched, densely aggregated, cylindrical, 10.5–15.0 × 1.8–2.5 μm. Conidiogenous cells 7.5–9.5 × 1.5–2.0 μm, cylindrical, terminal, straight to sinuous. Alpha conidia, hyaline, smooth, aseptate, ellipsoidal to fusiform, biguttulate, 3.8–5.0 × 1.5–2.3 µm (mean = 4.7 × 2.0 μm, n = 20). Beta conidia hyaline, aseptate, filiform, few guttulate, slightly curved, tapering towards both ends, 20.0–28.0 × 1.2–1.8 µm (mean = 23.2 × 1.2 μm, n = 20). Gamma conidia and sexual morph not observed.
Pure culture was isolated by subbing hyphal tips growing from surface sterilized plant material. Colonies on PDA cover the Petri dish diameter after incubation for 15 days in dark conditions at 25 °C. Aerial mycelium abundant, white, cottony on surface, reverse white to pale brown with two concentric zonation.
China, Yunnan Province: Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, on diseased leaves of Elaeagnus conferta. 19 April 2019, S.T. Huang, HSAUP194.12 paratype; living culture SAUCC194.12.
Diaporthe litchii comprises strains SAUCC194.12 and SAUCC194.22 can be distinguished from the closely related species D. collariana by 63 nucleotides difference in the concatenated alignment (9 in the ITS region, 34 TUB, 5 TEF and 15 CAL). Diaporthe litchii differs from D. collariana in smaller alpha conidia (3.8–5.0 × 1.5–2.3 vs. 4.7–5.6 × 1.7–2.2 μm) and shorter conidiophores (10.5–15.0 × 1.8–2.5 vs. 12–20 × 2.4–3.2 μm) (
Named after the host Chrysalidocarpus lutescens on which it was collected.
Diaporthe lutescens differs from D. pterocarpi (S. Hughes) D. Udayanga et al. and D. pseudoinconspicua T.G.L. Oliveira et al. in longer beta conidia and the types of conidia.
China, Yunnan Province: Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, on leaves of Chrysalidocarpus lutescens. 19 April 2019, S.T. Huang, HSAUP194.36, holotype, ex-holotype living culture SAUCC194.36.
Asexual morph: Conidiomata pycnidial, scattered or aggregated, black, erumpent, slightly raised above the surface of the culture medium, subglobose, exuding white creamy conidial droplets from central ostioles after 30 days incubation in light condition at 25 °C on PDA; pycnidial wall consists of black to dark brown, thin-walled cells. Conidiophores 10.2–17.0 × 1.8–3.0 μm, hyaline, unbranched, subcylindrical, septate, smooth, straight or slightly curved, obtuse at the apex, widened at base. Conidiogenous cells 5.7–9.1 × 1.4–2.6 μm, phialidic, cylindrical, terminal, straight to sinuous, tapering towards the apex. Beta conidia 20.8–28.8 × 1.2–2.0 μm (mean = 25.3 × 1.4 μm, n = 20), filiform, hyaline, straight or slightly curved, aseptate, base subtruncate, enlarged towards the apex. Alpha conidia and gamma conidia not observed.
Pure culture was isolated by subbing hyphal tips growing from surface sterilized infected plant material. Colonies on PDA cover the petri plate diameter after incubation for 15 days in dark conditions at 25 °C, initially white, becoming grayish, reverse pale brown, with concentric rings of dense and sparse hyphae, irregular margin, fluffy aerial mycelium. Pycnidia formed in 15 days.
From the phylotree, seen on Fig.
Named after the host Melastoma malabathricum on which it was collected.
Diaporthe melastomatis differs from D. parapterocarpi Crous in smaller α-conidia and the types of conidia.
Diaporthe melastomatis (SAUCC194.55) a branch with leaves of host plant b, c surface (b) and reverse (c) sides of colony after incubation for 15 days on PDA d conidiomata e, f conidiophores and conidiogenous cells g beta conidia h, i, k alpha conidia and beta conidia j alpha conidia. Scale bars: 10 μm (e–k).
China, Yunnan Province: Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, on diseased leaves of Melastoma malabathricum. 19 April 2019, S.T. Huang, HSAUP194.55, holotype, ex-holotype living culture, SAUCC194.55.
Asexual morph: Conidiomata pycnidial, subglobose to globose, black, erumpent, coated with white hyphae, thick-walled, yellowish spiral conidial cirrus exuded from ostioles. Conidiophores hyaline, smooth, septate, branched, densely aggregated, cylindric-clavate, straight to slightly sinuous, tapering towards the apex, 14.5–21.0 × 2.0–3.2 μm. Conidiogenous cells 9.5–13.0 × 1.5–2.5 μm, cylindrical, guttulate, terminal, tapering towards the base. Alpha conidia, hyaline, smooth, aseptate, oblong ellipsoidal, 2–4 guttulate, apex subobtuse, base subtruncate, 5.5–8.5 × 1.7–2.5 µm (mean = 6.8 × 2.1 μm, n = 20). Beta conidia abundant in the culture, hyaline, aseptate, filiform, multi-guttulate, sigmoid to lunate, mostly curved through 90–180°, tapering towards both ends, 25.0–33.5 × 1.1–2.0 µm (mean = 27.6 × 1.4 μm, n = 20). Gamma conidia and sexual morph not observed.
Pure culture was isolated by subbing hyphal tips growing from surface sterilized diseased material. Colonies on PDA cover the Petri diameter after incubation for 15 days in dark conditions at 25 °C, cottony and lobate with abundant aerial mycelium, hyphae white in the margin on surface side, with pale brown concentric ring of dense hyphae on reverse side.
China, Yunnan Province: Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, 19 April 2019, S.T. Huang. On diseased leaves of Millettia reticulata, HSAUP194.80 paratype, living culture SAUCC194.80; on infected leaves of Camellia sinensis, HSAUP194.88 paratype, living culture SAUCC194.88.
Diaporthe melastomatis is introduced based on the multi-locus phylogenetic analysis, with three isolates clustering separately in a well-supported clade (ML/BI = 100/1). Diaporthe melastomatis is most closely related to D. parapterocarpi, but distinguished based on ITS and TUB loci from D. parapterocarpi by 32 nucleotides difference in the concatenated alignment, in which 20 are distinct in the ITS region, 12 in the TUB region. Morphologically, Diaporthe melastomatis differs from D. parapterocarpi in its smaller alpha conidia (5.5–8.5 × 1.7–2.5 vs. 8.0–10.0 × 2.5–3.0 μm). Furthermore, Diaporthe melastomatis can produce beta conidia, but D. parapterocarpi cannot (
Named after the host Elaeagnus pungens on which it was collected.
Diaporthe pungensis differs from its closest phylogenetic species D. inconspicua R.R. Gomes et al. and D. poincianellae T.G.L. Oloveira et al. in ITS, TUB, TEF, CAL and HIS loci based on the alignments deposited in Tree-BASE.
China, Yunnan Province: Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, on diseased leaves of Elaeagnus pungens. 19 April 2019, S.T. Huang, HSAUP194.112, holotype, ex-holotype living culture SAUCC194.112.
Asexual morph: Conidiomata pycnidial, 3–5 pycnidia grouped together, superficial to embedded on PDA, erumpent, thin-walled, dark brown to black, globose or subglobose, exuding white creamy conidial mass from the ostioles. Conidiophores hyaline, aseptate, cylindrical, smooth, straight to sinuous, unbranched, 11.0–14.5 × 1.5–2.3 µm. Conidiogenous cells phialidic, cylindrical, terminal, 8.0–9.5 × 1.0–2.5 µm. Alpha conidia, hyaline, smooth, aseptate, ellipsoidal to fusoid, 2–3 guttulate, apex subobtuse, base subtruncate, 6.0–8.5 × 2.0–3.3 µm (mean = 6.6 × 2.5 μm, n = 20). Beta conidia hyaline, aseptate, eguttulate, filiform, slightly curved, tapering towards the apex, base truncate, some conidia are in the immature stage swollen in the middle, 24.0–28.9 × 1.0–2.0 µm (mean = 26.9 × 1.4 μm, n = 20). Gamma conidia not observed, sexual morph not observed.
Pure culture was isolated by subbing hyphal tips growing from surface sterilized plant material. Colonies on PDA cover the 3/4 of Petri dish diameter after incubation for 15 days in dark conditions at 25 °C, flat, cottony in the center with medium developed aerial mycelium, sparse in the outer region. With several concentric rings of dense and sparse hyphae, irregular margin, white on surface side, white to pale yellow and cinnamon speckle on reverse side.
China, Yunnan Province: Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, on infected leaves of Camellia sinensis. 19 April 2019, S.T. Huang, HSAUP194.89 paratype, living culture SAUCC194.89.
Diaporthe pungensis forms a distinct clade with high support (ML/BI = 100/1), and differed with the closely related species (D. inconspicua and D. poincianellae) on ITS, TUB, CAL and HIS loci (94% in ITS, 92% in TUB, 70% in TEF, 92% in CAL and 92% in HIS; and 95% in ITS, 94% in TUB, 80% in TEF, 94% in CAL and 89% in HIS, respectively). Moreover, Diaporthe pungensis differs from D. inconspicua, in having guttulate of alpha conidia, and having larger alpha conidia (6.0–8.5 × 2.0–3.3 vs. 5.5–6.5 × 1.5–2 μm) (
Asexual morph: Conidiomata pycnidial, multi-pycnidia grouped together, globose, black, erumpent, coated with white hyphae, creamy to yellowish conidial droplets exuded from central ostioles. Conidiophores hyaline, densely aggregated, cylindrical, straight to sinuous, tapering towards the apex, 13.5–23.0 × 2.0–3.0 μm. Alpha conidiogenous cells 7.0–10 × 1.8–2.5 μm, cylindrical, terminal, slightly curved. Beta conidiogenous cells 10.5–13.5 × 0.9–1.5 μm, cylindrical, hyaline, tapering towards the apex. Alpha conidia, hyaline, smooth, aseptate, ellipsoidal, multi-guttulate, apex subobtuse, base subtruncate, 4.7–5.8 × 2.4–2.9 µm (mean = 5.3 × 2.6 μm, n = 20). Beta conidia hyaline, aseptate, filiform, few guttulate, slightly curved, tapering towards the both ends, 25.5–32.0 × 1.0–1.6 µm (mean = 27.5 × 1.3 μm, n = 20). Gamma conidia and sexual morph not observed.
Pure culture was isolated by subbing hyphal tips growing from surface sterilized diseased material. Colonies on PDA cover the Petri dish diameter after incubation for 15 days in dark conditions at 25 °C. Aerial mycelium white, cottony, feathery, with concentric zonation, white on surface side, pale brown to black on reverse side.
China, Yunnan Province: Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, on infected leaves of Pometia pinnata. 19 April 2019, S.T. Huang, HSAUP194.66, living culture SAUCC194.66.
Diaporthe subclavata was originally described from the leaf with citrus scab of Citrus unshiu in Fujian Province, China (
Asexual morph: Conidiomata pycnidial, aggregated, brownish to black, erumpent, subglobose, exuding white creamy conidial droplets from central ostioles after being kept for 30 days in light at 25 °C. Conidiophores 17.4–35.0 × 2.2–3.5 μm, hyaline, branched, subcylindrical, septate, straight or slightly curved, guttulate. Conidiogenous cells 11.3–15.0 × 1.7–2.5 μm (mean = 12.3 × 2.1 μm, n = 20), cylindric-clavate, hyaline, straight to slightly sinuous, tapering towards the apex. Beta conidia 25.0–31.8 × 0.9–1.8 μm (mean = 28.2 × 1.2 μm, n = 20), filiform, hyaline, guttulate, aseptate, hooked and mostly curved through 90–180°, swollen in the middle. Alpha conidia and Gamma conidia not observed.
Pure culture was isolated by subbing hyphal tips growing from surface sterilized diseased material. Colonies on PDA cover the Petri dish diameter after incubation for 15 days in dark conditions at 25 °C, aerial mycelium abundant, white to grayish on surface side, pale yellow on reverse with concentric zonation. Pycnidia are formed on 15th day or later.
China, Yunnan Province: Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, 19 April 2019, S.T. Huang. On diseased leaves of Elaeagnus conferta HSAUP194.11, living culture SAUCC194.11; on diseased leaves of Pometia pinnata HSAUP194.63, living culture SAUCC194.63.
Diaporthe tectonendophytica was originally described from the asymptomatic branches of Tectona grandis in Thailand (
In the current study, 87 reference sequences (including an outgroup taxon) were selected based on BLAST searches of NCBIs GenBank nucleotide database and were included in the phylogenetic analyses (Table
Previously, species identification of Diaporthe was largely referred to the assumption of host-specificity, leading to the proliferation of names (
This work was jointly supported by the National Natural Science Foundation of China (no. 31770016, 31750001, and 31900014) and the China Postdoctoral Science Foundation (no. 2018M632699).