Pseudoberkleasmium chiangmaiense Y.Z. Lu & K.D. Hyde

Tian, Xingguo, Tibpromma, Saowaluck, Karunarathna, Samantha C., Dai, Dongqin, Lu, Yongzhong, Mapook, Ausana & Jayawardena, Ruvishika S., 2022, A new species and a new host record of Pseudoberkleasmium (Pseudoberkleasmiaceae, Dothideomycetes) from Cocos nucifera and Zea mays in northern Thailand, Phytotaxa 547 (3), pp. 232-242 : 235-236

Pseudoberkleasmium chiangmaiense Y.Z. Lu & K.D. Hyde , in Hyde et al., Fungal Diversity 96:38 ( FIGURE 2 )

Index Fungorum number: IF555595; Facesoffungi number: FoF 05310

Saprobic on decaying culms of Zea mays L. Sexual morph Undetermined. Asexual morph Hyphomycetous. Colonies on natural substratum superficial, sporodochia, scattered, compact, irregular, brown to black, glistening, with conidia readily liberated when disturbed. Conidiophores micronematous, mononematous, hyaline, reduced to conidiogenous cells, cylindrical, smooth-walled. Conidiogenous cells 7–11 × 8–11 μm (x̅ = 9 × 9.5 μm, n = 15), holoblastic, monoblastic, integrated, terminal, determinate, subglobose, hyaline, with guttulate. Conidia 24–30 × 15–18 μm (x̅ = 26.5 × 16.5 μm, n = 30), acrogenous, solitary, ellipsoidal to obovoid, muriform, 4–6 transverse septa, 3–4 longitudinal septa, flattened, smooth-walled, yellow-brown, constricted at the septa, with a hyaline conidiogenous cell attached.

Material examined:— THAILAND, Chiang Rai Province, Muang District, isolated as saprobic on decaying culms of Zea mays (Poaceae) , 11 November 2020, X. G. Tian, corn1–7 ( MFLU 21–0290 , new host record) .

Notes:— Phylogenetic analyses showed that our new isolate (MFLU 21–0290) grouped with two strains of P. chiangmaiense (MFLUCC 17–1809 and MFLUCC 17–2088) with strong statistical support (100 ML/1.00 PP, FIGURE 1 ). The morphology of our new isolate is similar to the holotype of P. chiangmaiense (MFLU 17–1118) except the smaller conidiogenous cells (x̅ = 9 × 9.5 μm vs. x̅ = 15 × 14 µm) ( Hyde et al. 2019). Based on nucleotide comparisons, the new strain (MFLU 21–0290) is not significantly different from the ex-type isolate (MFLUCC 17–1809) in ITS, LSU and TEF-α. Therefore, we identified our isolate as P. chiangmaiense based on both phylogeny and morphology.

Pseudoberkleasmium chiangmaiense was introduced by Hyde et al. (2019) from an unidentified decaying wood in Thailand. Phukhamsakda et al. (2020) reported the new host record of P. chiangmaiense from Clematis fulvicoma , while, Bao et al. (2021) reported P. chiangmaiense from freshwater in China. Our collection was on Zea mays and herein we provide the first host record of P. chiangmaiense from Maize.

Figures

FIGURE 1. RAxML tree based on analyses of combined LSU, SSU, ITS, TEF1-α and RPB2 dataset. The tree is rooted with Lophiostoma crenatum (CBS 629.86) and L. arundinis (CBS 621.86). Bootstrap values for ML ≥ 75% and Bayesian posterior probabilities (PP) ≥ 0.95 are labelled on the nodes. The newly obtained sequences are indicated in red, while type strains are in black/red bold.

FIGURE 2. Pseudoberkleasmium chiangmaiense (MFLU 21–0290, new host record). a, b.Appearanceof conidiomata on host substrate. c–g. Conidia attached to conidiogenous cells (arrows indicate conidiogenous cells). h–l. Conidia. Scale bars: a =1000 µm, b = 300 µm, c–d = 50 µm, e–m = 20 µm.