Symmetrospora rhododendri Q.M. Wang, F.Y. Bai & A.H. Li, 2020

Li, A. - H., Yuan, F. - X., Groenewald, M., Bensch, K., Yurkov, A. M., Li, K., Han, P. - J., Guo, L. - D., Aime, M. C., Sampaio, J. P., Jindamorakot, S., Turchetti, B., Inacio, J., Fungsin, B., Wang, Q. - M. & Bai, F. - Y., 2020, Diversity and phylogeny of basidiomycetous yeasts from plant leaves and soil: Proposal of two new orders, three new families, eight new genera and one hundred and seven new species, Studies In Mycology 96, pp. 17-140 : 115-116

Symmetrospora rhododendri Q.M. Wang, F.Y. Bai & A.H. Li sp. nov. MycoBank MB828821. Fig. 15K, L .

Etymology: the specific epithet rhododendri refers to Rhododendron , the plant genus from which the type strain was isolated.

Culture characteristics: In YM broth, after 7 d at 17 °C, cells are cylindrical and ellipsoidal, 3.4–4.7 × 6.6– 9.4 μm and single, budding is polar ( Fig. 15K ), a sediment is formed. After 1 mo at 17 °C, a part ring and sediment are present. On YM agar, after 1 mo at 17 °C, the streak culture is pinkish orange, butyrous, slight wrinkled and glossy. The margin is entire. In Dalmau plate culture on corn meal agar, pseudohyphae are not formed. Sexual structures are not observed on YM, PDA, V8 and CM agar. Ballistoconidia are ellipsoidal to long ovoid, 1.7– 3.6 × 5.0– 7.1 μm ( Fig. 15L ).

Physiological and biochemical characteristics: Glucose fermentation is absent. Glucose, galactose, L-sorbose (delayed), sucrose, trehalose, melibiose, L-arabinose, glycerol, ribitol (weak), D-mannitol, D-glucitol and succinate (weak) are assimilated as sole carbon sources. Maltose, cellobiose, lactose, melezitose, raffinose, inulin, soluble starch, D-xylose, D-arabinose, D-ribose, L-rhamnose, D-glucosamine, N-Acetyl-D-glucosamine, methanol, ethanol, erythritol, galactitol, Methyl-α- D-glucoside, salicin, DLlactate, citrate, myo-inositol and hexadecane are not assimilated. Ammonium sulfate, potassium nitrate and L-lysine are assimilated as sole nitrogen sources. Sodium nitrite, ethylamine hydrochloride and cadaverine dihydrochloride are not assimilated. Maximum growth temperature is 25 °C. Growth in vitamin-free medium is positive. Starch-like substances are not produced. Growth on 50 % (w/w) glucose-yeast extract agar is negative. Urease activity is positive. Diazonium Blue B reaction is positive.

Physiologically, Sy. rhododendri differs from its closely related species Sy. coprosmae and Sy. oryzicola in its inability to assimilate L-sorbose, cellobiose, melezitose, D-arabinose, D- ribose, Methyl-α- D-glucoside, salicin and DL-lactate and its ability to assimilate lactose, inulin, nitrate and cadaverine ( Table S1.25 ).

Typus: China, Lulang county, Tibet, obtained from a leaf of Rhododendron sp. , Sep. 2004, F.-Y. Bai (holotype CGMCC 2.2613 T preserved in a metabolically inactive state, ex-type CBS 15447 = XZ49DX).

Figures

Fig. 15. Vegetative cells grown in YM broth for 5 d at 17 °C and ballistoconidia produced on corn meal agar after 7 d at 17 °C. (A, B) Phy. aceris CGMCC 2.2662T; (C) Phy. jiayinensis CGMCC 2.5669T; (D) Me. layueensis CGMCC 2.5818T; (E) Sa. melibiophila CBS 5143T; (F) Mi. ellipsoideus CGMCC 2.5664T; (G, H) Mi. rubellus CGMCC 2.4444T; (I, J) Mi. pseudomagnisporus CGMCC 2.4538T; (K, L) Sy. rhododendri CGMCC 2.2613T; (M) Cy. raffinophilum CGMCC 2.3822T; (N) Cy. terricola CGMCC 2.3823T, (O) Do. ningxiaensis CGMCC 2.4451T; (P) Beg. foliicola CGMCC 2.3164T. Bars = 10 μm.