Colletotrichum jiangxiense F. Liu & L. Cai

Gomdola, Deecksha, Jeewon, Rajesh, McKenzie, Eric H. C., Jayawardena, Ruvishika S., Al-Otibi, Fatimah, Tang, Xia, Wang, Yong, Hyde, Kevin D. & Fu, Li, 2025, Phylogenetic diversity of Colletotrichum species (Sordariomycetes, Glomerellales, Glomerellaceae) associated with plant diseases in Thailand, MycoKeys 119, pp. 137-195 : 137-195

Colletotrichum jiangxiense F. Liu & L. Cai , in Liu et al. Persoonia 35: 82 (2015)

Figs 2 , 10

Description.

Associated with leaf spots of Artocarpus sp. Leaf spots circular, oval, or irregular, pale brown to brown, surrounded with a dark brown margin. Sexual morph: Not observed. Asexual morph on substrate: Conidiomata 200–500 × 150–400 µm (x ̄ = 300 × 200 µm, n = 10), acervular, semi-immersed, scattered or gregarious, globose to subglobose, dark brown to black, erumpent, exuding creamy orange conidial mass. Setae not observed. Asexual morph on PDA: Conidiomata 200–1000 µm diam. (x ̄ = 400 µm, n = 10), semi-immersed, scattered or gregarious, globose to subglobose, dark brown to black, exuding creamy orange conidial mass. Setae not observed. Conidiophores hyaline, sometimes branched. Conidiogenous cells 12–19 × 2–5 µm (x ̄ = 14.9 × 3.2 µm, n = 10), hyaline, cylindrical to ampulliform, straight or flexuous. Conidia 14–21 × 4–6.5 µm (x ̄ = 16.5 × 5.2 µm, n = 30; L / W ratio = 3.2), hyaline, cylindrical to ellipsoidal, smooth-walled, guttulate, aseptate, with rounded ends (sometimes tapering towards one end), forming conidial anastomosis tubes. Conidial anastomosis tubes 2–16 × 1–2 µm (x ̄ = 8.2 × 1.5 µm, n = 10), hyaline, smooth-walled, aseptate. Appressoria not observed.

Culture characteristics.

Colonies on PDA reaching approximately 55 mm diam. after 7 d of incubation at 25 ° C; mycelium white to grey, elevation flat, cottony, with an entire margin.

Specimen examined.

Thailand • Chiang Mai: Omkoi District, Yiang Piang Subdistrict , associated with leaf spots of Artocarpus sp. ( Moraceae ), 16 Oct 2019, D. Gomdola DG 360 ( MFLU 25-0017 ), living culture MFLUCC 25-0018 .

GenBank.

ITS = PV 263305; TUB 2 = PV 295627; H 3 = PV 400149.

Known hosts, distributions, and lifestyles

(listed chronologically). Endophytic on Camellia sinensis in China ( Liu et al. 2015; Jayawardena et al. 2016 a).

Pathogenic; brown lesions on leaves of Camellia sinensis in China ( Liu et al. 2015).

Anthracnose on fruits of Persea americana in Mexico (Ayvar-Serna et al. 2020; Fuentes-Aragón et al. 2020 b).

Leaf spots of Fraxinus americana in China ( Chang et al. 2023).

Associated with leaf spots of Artocarpus sp. in Thailand (this study).

Notes.

Our isolate ( MFLUCC 25-0018 ) grouped with Colletotrichum jiangxiense ( CGMCC 3.1736, 22 N 642, SYD- 9, and SYD- 4) with 90 % ML support (Fig. 2 ). However, this clade has low support for other species. Similar to the study conducted by Liu et al. (2015), this research shows that C. jiangxiense is located in the C. gloeosporioides species complex (Figs 1 , 2 ). Nucleotide sequence comparisons between our isolate and C. jiangxiense ( CGMCC 3.17363) showed no difference in the ITS (505 bp) and TUB 2 (667 bp) regions.

MFLUCC 25-0018 morphologically resembles the ex-type of C. jiangxiense ( CGMCC 3.17363), having hyaline, aseptate, smooth-walled, and cylindrical conidia ( Liu et al. 2015). The conidial L / W ratio of our isolate is close to that of C. jiangxiense ( CGMCC 3.17363) (L / W ratio = 2.9 vs. 3.2).

Based on phylogenetic and morphological species concepts, we identify our isolate as Colletotrichum jiangxiense . This study represents the first report of C. jiangxiense associated with leaf spots on Artocarpus sp. and establishes a new geographical record in Thailand.

Figures

Figure 1. Maximum likelihood analysis (IQ-tree) based on a combined dataset of ITS, GAPDH, CHS 1, ACT, TUB 2, H 3, and CAM sequences from dataset 1, which includes all Colletotrichum species. Bootstrap support values (ML ≥ 80 %) and Bayesian posterior probabilities (PP ≥ 0.95) are given above the branches or near the nodes as ML / PP. Hyphens (--) indicate bootstrap support values below 80 % for ML and posterior probabilities below 0.95. The tree is rooted with Monilochaetes infuscans (CBS 869.96) and M. melastomae (CBS 145059). Type, ex-type, and reference species are denoted with T. Our isolates are in bold red font, while our new species are in bold blue font. Different color blocks represent distinct species complexes, with a single color used to denote singleton species.

Figure 2. Maximum likelihood analysis (IQ-tree) based on a combined dataset of ITS, GAPDH, CHS 1, ACT, TUB 2, H 3, and CAM sequences from dataset 2, which includes all species in the C. gloeosporioides species complex. Bootstrap support values (ML ≥ 80 %) and Bayesian posterior probabilities (PP ≥ 0.95) are given above the branches or near the nodes as ML / PP. Hyphens (--) indicate bootstrap support values below 80 % for ML and posterior probabilities below 0.95. The tree is rooted with C. beeveri (CBS 128527) and C. boninense (CBS 123755), belonging to the C. boninense species complex. Type, ex-type, and reference species are denoted with T. Our isolates are in bold red font. Different color blocks represent distinct species complexes.

Figure 10. Colletotrichum jiangxiense. a. Leaf spots (Artocarpus sp.); b. Conidiomata on substrate; c. Top and reverse of colony on PDA after 7 d; d, e. Conidiogenesis and developing conidia; f, g. Conidia; h. Conidia forming conidial anastomosis tubes. Scale bars: 200 μm (b); 50 μm (d); 20 μm (e); 10 μm (f – h).