Kockovaella iteae C. Y. Chai & F. L. Hui, 2024

Chai, Chun-Yue, Xi, Zhi-Wen, Niu, Qiu-Hong & Hui, Feng-Li, 2024, Three new species of the genus Kockovaella (Cuniculitremaceae, Tremellales) from the phylloplane in China, MycoKeys 110, pp. 237-253 : 237-253

Kockovaella iteae C. Y. Chai & F. L. Hui sp. nov.

Fig. 3

Etymology.

The specific epithet iteae refers to Itea, the plant genus from which the type strain was isolated.

Type.

China • Guizhou Prov.: Guiyang City, East Mountain Park , in the phylloplane of Itea yunnanensis , 15 Sept 2023, D. Lu, NYNU 239240 (holotype GDMCC 2.503 T preserved as a metabolically inactive state, culture ex-type PYCC 9996 ) .

Description.

On YM agar after 7 days at 20 ° C, the streak culture is white to cream-colored, butyrous, smooth and glistening, with an entire margin. After 7 days in YM broth at 20 ° C, cells are ellipsoidal or ovoid, 1.5–3.6 × 3.6–5.5 μm, single or pairs, and reproduced by polar budding and the formation of stalked conidia. The conidia are separated at the distal end of the stalks from parent cells. After 1 month at 20 ° C, a ring and sediment are present. In Dalmau plate culture on CMA, pseudohyphae are not formed. Sexual structures are not observed on PDA, CMA or V 8 agar. Ballistoconidia are symmetrical and apiculate, 1.8–2.4 × 2.7–3.3 μm. Glucose fermentation is absent. Glucose, inulin (delayed and weak), sucrose, raffinose, melibiose, galactose, lactose, trehalose, maltose, melezitose, cellobiose, salicin (delayed and weak), L-rhamnose, D-xylose, L-arabinose, D-arabinose (delayed), 5 - keto-D-gluconate (delayed and weak), D-ribose (delayed), erythritol (delayed), ribitol, galactitol, D-mannitol, D-glucitol, myo-inositol, succinate, citrate, D-glucosamine, N-acetyl-D-glucosamine, 2 - keto-D-gluconate (delayed), D-glucuronate, and glucono- 1.5 - lactone are assimilated as sole carbon sources. Methyl-α-D-glucoside, L-sorbose, methanol, ethanol, glycerol, DL-lactate, and D-gluconate are not assimilated. Ethylamine (delayed) and L-lysine are assimilated as sole nitrogen sources. Nitrate, nitrite, and cadaverine are not assimilated. Maximum growth temperature is 25 ° C. Growth in vitamin-free medium is positive. Growth on 50 % (w / w) glucose-yeast extract agar is negative. Starch-like substances are not produced. Urease activity is positive. Diazonium Blue B reaction is positive.

Additional strain examined.

China • Guizhou Prov.: Guiyang City, East Mountain Park , in the phylloplane of Itea yunnanensis , 15 Sept 2023, D. Lu, NYNU 239246 .

GenBank accession numbers.

holotype GDMCC 2.503 T ( ITS: OR 958773, D 1 / D 2: OR 958772, RPB 1: PP 755337); additional strains NYNU 239246 ( ITS: PP 752297, D 1 / D 2: PP 752296, RPB 1: PP 755338).

Note.

Physiologically, Kockovaella iteae sp. nov. differs from six closely related species, K. calophylli , K. cucphuongensis , K. litseae , K. quanzhouensis , K. schimae , and K. vietnamensis , in its ability to assimilate inulin and ethylamine (Table 3 ).

Figures

Figure 3. Morphological characteristics of Kockovaella iteae sp. nov. NYNU 239240 T A colony morphology on YM agar after growth for 7 d at 20 ° C B budding cells after growth for 7 d in YM broth at 20 ° C C stalked conidia on PDA after growth for 7 d at 20 ° C D ballistoconidia on CM agar after growth for 7 d at 20 ° C. Scale bars: 10 μm.