Dioszegia guizhouensis Y.Z. Qiao & F.L. Hui, 2024

Qiao, Ya-Zhuo, Liu, Shan, Niu, Qiu-Hong & Hui, Feng-Li, 2024, Three new Dioszegia species (Bulleribasidiaceae, Tremellales) discovered in the phylloplane in China, MycoKeys 101, pp. 313-328 : 313

Dioszegia guizhouensis Y.Z. Qiao & F.L. Hui sp. nov.

Fig. 2A

Etymology.

The specific epithet guizhouensis refers to the geographic origin of the type strain, Guizhou province.

Typus.

China, Guizhou Province, Guiyang City, Guiyang Botanical Garden, in the phylloplane of Schisandra sp., September 2022, L. Zhang and F.L. Hui, NYUN 22985 (holotype GDMCC 2.311T preserved as a metabolically inactive state, culture ex-type PYCC 9938).

Description.

On YM agar, after 7 days at 20 °C, the streak culture is pink to orange, butyrous, smooth. The margin is entire. On YM agar, after 7 days at 20 °C, cells are ovoid and ellipsoidal, 2.8-4.6 × 4.1-6.8 μm and single, budding is polar. After 1 month at 20 °C, a ring and sediment are present. In Dalmau plate culture on corn meal agar, hyphae and pseudohyphae are not formed. Sexual structures are not observed for individual strains and strain pairs on PDA, CM agar, and YCBS agar for two months. Ballistoconidia are not produced on CM agar after two weeks at 20 °C. Glucose fermentation is absent. Glucose, sucrose, raffinose, melibiose, galactose, trehalose, maltose, melezitose, cellobiose, salicin, L-sorbose (delayed), L-rhamnose, D-xylose, L-arabinose, D-arabinose, 5-keto-D-gluconate (weak), D-ribose, galactitol, D-mannitol, D-glucitol, succinate (weak), citrate, D-gluconate, N-acetyl-D-glucosamine, 2-keto-D-gluconate, D-glucuronate, and glucono-1,5-lactone are assimilated as carbon sources. Inulin, lactose, methyl-α-D-glucoside, methanol, ethanol, glycerol, erythritol, ribitol, myo-inositol, DL-lactate, and D-glucosamine are not assimilated. Nitrite is assimilated as the sole nitrogen source. Nitrate, ethylamine, L-lysine, and cadaverine are not assimilated. Maximum growth temperature is 30 °C. Growth in vitamin-free medium is positive. Starch-like substances are produced. Urease activity is positive. Diazonium Blue B reaction is positive.

Additional strain examined.

China, Guizhou Province, Guiyang City, Guiyang Botanical Garden, in the phylloplane of Mussaendae sp., September 2022, L. Zhang and F.L. Hui, NYUN 229195.

GenBank accession numbers.

Holotype NYUN 22985T (ITS: OP566883, D1/D2: OP566880); additional strain 229195 (ITS: OP566896, D1/D2: OP581919).

Note.

Dioszegia guizhouensis sp. nov. can be physiologically differentiated from its closest known species D. hungarica ( Takashima and Nakase 2011) by its inability to assimilate D-glucosamine, its ability to assimilate melibiose and L-sorbose, and its capacity to grow in vitamin-free medium and at 30 °C.

Figures

Figure 2. Vegetative cells of Dioszegia guizhouensis sp. nov. NYNU 22985 T (A), Dioszegia foliicola sp. nov. NYUN 229182 T (B), and Dioszegia aurantia sp. nov. NYNU 229189 T (C) following growth in YM broth for 7 days at 20 ° C. Scale bars: 10 μm.