Tubakia dryinoides C. Nakash., Fungal Systematics and Evolution 1: 80 (2018)

Zhang, Zhaoxue, Mu, Taichang, Liu, Shubin, Liu, Rongyu, Zhang, Xiuguo & Xia, Jiwen, 2021, Morphological and phylogenetic analyses reveal a new genus and two new species of Tubakiaceae from China, MycoKeys 84, pp. 185-201 : 185

Tubakia dryinoides C. Nakash., Fungal Systematics and Evolution 1: 80 (2018)

Fig. 5

Description.

Asexual morph: Living as endophyte in leaves, forming distinct leaf lesions, shape and size variable, subcircular to angular-irregular, pale brown to brown. Colonies on PDA incubated at 25°C in the dark with an average radial growth rate of 5-7 mm/d and occupying an entire 90 mm Petri dish in 14 d, forming some conspicuous concentric circles, aerial mycelium cottony, white initially, then becoming greyish-sepia. Conidiomata sporodochial, appeared within 14 days or longer, formed on agar surface, slimy, black, semi-submerged. Sporodochial conidiophores densely and irregularly branched, 11.0-24.0 μm × 1.5-5.0 μm, bearing apical whorls of 2-3 phialides; sporodochial phialides monophialidic, subulate to subcylindrical, 9.0-16.0 μm × 1.5-5.0 μm, smooth, thin-walled, apex obtuse to truncate, sometimes forming indistinct periclinal thickenings. Conidia solitary, ellipsoid to obovoid, 6.5-14.0 μm × 4.0-6.0 μm, wall thin, up to 1.0 μm, hyaline to subhyaline, smooth, apex and base broadly rounded, with inconspicuous to conspicuous basal hilum (frill), occasionally somewhat peg-like and truncate when conspicuous. Microconidia not observed. Sexual morph not observed.

Culture characteristics.

Cultures incubated on MEA at 25°C in darkness, attaining 38.0-42.0 mm diam. after 14 d (growth rate 2.7-3.0 mm diam./d), margin scalloped, at first creamy white, grey near the centre, reverse light brown to dark, with olivaceous edge. Conidial formation not observed.

Specimen examined.

China, Shandong Province: Zibo Lushan National Forest Park, on diseased leaves of Quercus palustris ( Fagaceae ), 20 Sep 2020, Z. X. Zhang, HSAUP1924, living culture SAUCC 1924.

Notes.

Braun et al. (2018) described Tubakia dryinoides , based on morphological and molecular data. The holotype of T. dryinoides (NBRC H-11618) was collected from Quercus phillyraeoides A. Gray ( Braun et al. 2018). In our current research, isolate (SAUCC 1924) collected from diseased leaves of Quercus palustris clustered in the Tubakia dryinoides clade by strong support (Figs 1 and 2 ). We, therefore, consider the isolated strain (SAUCC 1924) as T. dryinoides . The conidiomata of T. dryinoides is only known from true pycnothyria and the sporodochial conidiomata of the isolated strain (SAUCC 1924) is new for T. dryinoides ( Braun et al. 2018). Additionally, the conidia of our isolate (SAUCC 1924) is narrower than the original description of T. dryinoides (4.0-6.0 μm vs. 5.5-10.0 μm; Braun et al. 2018).

Figures

Figure 1. Phylogram of Tubakiaceae, based on the concatenated ITS, LSU and rpb 2 sequence alignment. The BI and ML bootstrap support values above 0.74 and 74 % are shown at the first and second position, respectively. The tree is rooted to Greeneria uvicola (culture FI 12007) and ex-type cultures are indicated in bold face. Strains from the current study are in red. Some branches were shortened for layout purposes - these are indicated by two diagonal lines with the number of times a branch was shortened indicated next to the lines.

Figure 2. Phylogram of Tubakiaceae, based on the concatenated ITS, tef 1 and tub 2 sequence alignment. The BI and ML bootstrap support values above 0.74 and 74 % are shown at the first and second position, respectively. The tree is rooted to Greeneria uvicola (culture FI 12007) and ex-type cultures are indicated in bold face. Strains from the current study are in red. Some branches were shortened for layout purposes - these are indicated by two diagonal lines with the number of times a branch was shortened indicated next to the lines.

Figure 5. Tubakia dryinoides (SAUCC 1924). a diseased leaf of Quercus palustris; b surface of colony after 15 days on MEA; c reverse of colony after 15 days on MEA; d conidiomata; e-g conidiophores, conidiogenous cells with conidia; h-i conidia. Scale bars: 10 μm (e-i).