Neofusicoccum parvum (Pennycook & Samuels) Crous, Slippers & A.J.L. Phillips

Ma, Xiao-Ya, Hyde, Kevin D., Phillips, Alan J. L., Kang, Ji-Chuan, Chomnunti, Putarak & Doilom, Mingkwan, 2021, Three new host records of endophytic Neofusicoccum species reported from Dendrobium orchids, Phytotaxa 494 (2), pp. 193-207 : 198-202

Neofusicoccum parvum (Pennycook & Samuels) Crous, Slippers & A.J.L. Phillips

( FIGURES. 3–4 )

= Neofusicoccum italicum Dissan. & K.D. Hyde (IF: 820799), in Marin-Felix et al., Stud. Mycol. 86: 170 (2017)

Description:— Colony on PDA superficial, yellow brown with white irregular and loose margin, felty, with concentric rings, water drops secretion densely on the surface; reverse flat, yellow brown with white irregular and loose margin; growth rate: 2.4 mm /day. Vegetative mycelia 1–4 μm diam, hyaline to brown, smooth, septate, dense. Conidiomata 200–500 μm, stromatic, globose to subglobose, solitary or aggregated, black, uni- to multi-locular, ostiolate. Ostiole circle, lateral. Conidiomatal walls consisting of thick-walled, brown to dark brown cells of textura angularis in the outer layers, becoming hyaline in the inner layers. Conidiophores reduced to conidiogenous cell. Conidiogenous cell enteroblastic, phialidic, hyaline, cylindrical, determinate, integrated, smooth. Conidia (14–) 15–17 (–18) × (5–) 5.5–6 (–6.5) μm (x = 16 × 6 μm, L:W = 2.8), fusiform to ellipsoid with obtuse apex and slightly truncate end, hyaline, smooth, with dense cytoplasm.

Colony on WA superficial, white with grey mycelia, irregular edge, fluffy, reverse dark grey, centre black, growth rate: 1.3 mm /day. On WA (slide culture), vegetative mycelia 1–3.5 μm diam, hyaline to brown, smooth, septate, dense. Conidiomata found on the rubber band in slide culture, dark brown to black, stromatic, pycnidial, solitary to aggregated, globose to sub-globose, multi-locular, glabrous, ostiolate. Ostiole circle, central. Conidiomatal wall consisting of thick-walled, brown to dark brown cells of textura angularis in the outer layers, becoming hyaline cells in the inner layers. Conidiophores reduced to conidiogenous cells. Conidiogenous cell 9–33 × 2–3 μm, rising from inner layers, enteroblastic, phialidic, hyaline, cylindrical to subcylindrical, determinate, integrated, smooth and thick-walled. Conidia (11–) 12 – 14 (–15.5) × (5–) 6 – 6.5 (–7) μm (x = 13 × 6 μm; L:W = 2.3), hyaline, oval, fusiform to ellipsoidal with obtuse apex and slightly truncate base, aseptate, smooth, thick-walled, with guttules.

in bold. Maximum likelihood (ML) and Bayesian posterior probabilities (PP) are labelled at the nodes (50% majority rule). Dashes are indicated values lower than 50%. The scale bar corresponds to 0.02 substitutions per site.

Material examined:— THAILAND, Chiang Rai Province, Wat Phra That Doi Tung ( Temple of Doi Tung Pagoda ), endophytic in the leaf of Dendrobium harveyanum , 19 December 2013, S . Nontachaiyapoom , N . Aewsakul & X. Y . Ma , living culture, MFLUCC 14-0163 ; Chiang Rai Province, Mae Sai District, Huaykrai Mai Temple , endophytic in the leaf of D. moschatum , 10 May 2015, S . Nontachaiyapoom , B . Mala & X. Y Ma , living culture, MFLUCC 15-1171 ; China , Guizhou Province, Xingyi City , orchid nursery, endophytic in the stem of Dendrobium spp. , 4 October 2019, B. W . Chen , living culture, MFLUCC 19-0242 and MFLUCC 19-0244 .

Notes:— The sequences of isolates MFLUCC 14-0163, MFLUCC 15-1171, MFLUCC 19-0242 and MFLUCC 19-0244 have less than 1% different base pairs. The blast results showed that they were most similar to Neofusicoccum parvum . There were four different base pairs between MFLUCC 19-0244 and the ex-type strain of N. parvum CMW 9081 (1 in ITS, 2 in EF-1α and 1 in RPB 2). The characteristics, which do not separate the four strains, are very similar with the type strain CMW 9081 and that of pathogenic strains of N. parvum ( Ismail et al. 2013) . Thus, we consider our isolates to be N. parvum .

Neofusicoccum italicum ( MFLUCC 15-0900) clustered with the N. algeriense / N. parvum group in this study (2 base pairs differences in ITS). Neofusicoccum algeriense was regarded as a synonym of N. parvum ( Lopes et al. 2017) , therefore, we also regard N. italicum as a synonym of N. parvum . A comparison of characters is given in TABLE 3.

Figures

FIGURE 3. Neofusicoccum parvum (MFLUCC 14-0163). A–B. Colony on PDA (A. surface, B. reverse). C–G. Conidiomata on PDA. H. Conidiogenous cells with conidia. I. Conidiogenous cell with conidium stained with Congo red. J–M. Conidia (I, L, M stained with Congored). Scale bars: C= 200 μm, D=500 μm, H=20 μm, I–K =10 μm, L–M=5 μm.

FIGURE 4. Neofusicoccum parvum (MFLUCC 19-0244, C–N from WA).A–B. Colony on PDA (A: surface, B: reverse). C. Conidiomata on slide culture. D–G. Pycnidia. H–L. Conidiogenous cells with conidia. M–N. Conidia. Scale bars: H=10 μm, I–J=5 μm, K–N=10 μm.