Neodeightonia phoenicum A.J.L. Phillips & Crous

Rathnayaka, Achala R., Chethana, K. W. Thilini, Phillips, Alan J. L. & Jones, E. B. Gareth, 2022, Two new species of Botryosphaeriaceae (Botryosphaeriales) and new host / geographical records, Phytotaxa 564 (1), pp. 8-38 : 28-31

Neodeightonia phoenicum A.J.L. Phillips & Crous , in Phillips et al., Persoonia 21: 43 (2008)

Index Fungorum number: IF 511708; Facesoffungi number: FoF 11670, Fig. 13

Saprobic on dead leaf base of Phoenix reclinata . Sexual morph: Undetermined. Asexual morph: Coelomycetous. Conidiomata 90–150 μm high × 75–100 μm diam. (x̄ = 120 × 88 μm, n = 10), pycnidial, solitary or gregarious, subglobose, multiloculate, dark brown to black, immersed, becoming erumpent at maturity. Conidiomata wall 10–30 μm wide, two-layered, outer layer composed of thick-walled, dark brown cells of textura angularis, inner layer composed of thin-walled, pale brown to hyaline cells of textura angularis. Conidiophores usually reduced to conidiogenous cells. Conidiogenous cells 5–10 × 2–5 μm (x̄ = 7.4 × 3 μm, n = 20), lining the pycnidial cavity, holoblastic, hyaline, cylindrical, discrete, determinate, smooth-walled. Conidia 11–17 × 6–10 μm (x̄ = 14 × 8.5 μm, n = 20), ovoid to ellipsoid, straight, broadly rounded at both ends, hyaline, aseptate, guttulate.

Culture characteristics: — Conidia germinating on PDA within 24 h. Germ tubes produced from one side of the conidium. Colonies on PDA reaching 5–6.5 cm diam. after 4 days at 25 °C, circular, flattened, fluffy, medium dense, aerial, grey in top view and black in reverse.

Material examined:— THAILAND. Chiang Rai: near Public at Rajabath university, on a dead leaf base of Phoenix reclinata (Arecaceae) , 12 June 2020, Achala Rathnayaka (MFLU 22-0096, new host and geographical record), living culture MFLUCC 22-0061.

Known hosts and distribution:— Phoenix canariensis in Spain ( Phillips et al. 2008, Liu et al. 2010), P. dactylifera in California and Spain ( Phillips et al. 2008, Liu et al. 2010), Phoenix sp. in Greece ( Ligoxigakis et al. 2013), and P. reclinata in Thailand (this study).

Notes:—Morphologically, our collection (MFLUCC 22-0061) is similar to the holotype of Neodeightonia phoenicum (CBS 122528) collected from Phoenix sp. in Spain ( Phillips et al. 2008). Both collections have dark brown to black, multiloculate, erumpent conidiomata. Conidiogenous cells are holoblastic, hyaline, cylindrical, and conidia are ovoid to ellipsoid. However, the size of the conidia of our new collection (x̄ = 14 × 8.5 μm) is smaller than the extype strain (x̄ = ± S.D. = 19.1 ± 1.7 × 11.5 ± 1.1 μm) ( Phillips et al. 2008). In the multi-gene phylogeny (ITS, LSU, SSU, and tef 1-α), our strain together with the ex-type and other strains of N. phoenicum (CBS 122528, CBS 123168 and CBS 169.34) clustered with relatively high 100% ML bootstrap and 1.00 PP support ( Fig. 3 ). Based on morphmolecular analyses, we introduce our collection as a new host record of N. phoenicum from Phoenix reclinata and also as a new geographical record from Thailand.

Figures

FIGURE 3. Phylogram generated from ML analysis based on combined dataset of ITS, LSU, SSU, and tef1-α. The tree is rooted to Diplodia mutila (CBS 112553) and D. rosulata (CBS 116470). Tree topology is similar to previous study conducted by Phukhamsakda et al. (2022). Bootstrap support values for ML ≥ 70% and Bayesian posterior probabilities (PP) ≥ 0.90 are noted at the nodes. Strain numbers are noted after the species names. Strains isolated in this study are presented in red and type strains are in bold.

FIGURE 13. Neodeightonia phoenicum on dead leaf base of Phoenix reclinata (MFLU 22-0096). a, b. Host. c, d. Appearance of conidiomata on host surface. e. Section through conidiomata. f. Section through peridium. g–j. Conidiogenous cells. k−n. Conidia. o. Germinating conidium. p, q. Colony on PDA (p upper, q lower). Scale bars: c = 2 mm, d = 100 μm, e = 50 μm, f, g = 5 μm, h–o = 10 μm.