Diaporthe camelliae-oleiferae Q. Yang, 2021

Yang, Qin, Tang, Jie & Zhou, Guo Y., 2021, Characterization of Diaporthe species on Camellia oleifera in Hunan Province, with descriptions of two new species, MycoKeys 84, pp. 15-33 : 15

Diaporthe camelliae-oleiferae Q. Yang sp. nov.

Figure 2

Diagnosis.

Distinguished from the phylogenetically closely-related species, D. pandanicola and D. viniferae based on DNA sequence data.

Etymology.

Named after the host species, Camellia oleifera .

Description.

Asexual morph: pycnidia on PDA 500-660 μm in diam., superficial, scattered on PDA, dark brown to black, globose, solitary, or clustered in groups of 3-5 pycnidia. Pale yellow conidial drops exuding from ostioles. Conidiophores reduced to conidiogenous cells. Conidiogenous cells (7.5-)10-14(-15.5) × 1.5-2.3 μm (n = 30), aseptate, cylindrical, straight, densely aggregated, terminal, slightly tapered toward the apex. Alpha conidia 5-6.5(-7.5) × 1.9-2.3 μm (n = 30), aseptate, hyaline, ellipsoidal to fusiform, biguttulate. Beta conidia (26.5-)28.5-31(-33) × 0.8-1.2 µm (n = 30), hyaline, aseptate, filiform, sinuous at one end, eguttulate.

Culture characters.

Culture incubated on PDA at 25 °C, originally flat with white fluffy aerial mycelium, becoming brown to black in the centre, with yellowish-cream conidial drops exuding from the ostioles after 20 days.

Specimens examined.

China. Hunan Province: Zhuzhou City , on leaves of Camellia oleifera , 27°2'41"N, 113°19'17"E, 14 Aug. 2020, Q. Yang (holotype CSUFT027; ex-type living culture: HNZZ027; other living cultures: HNZZ030 and HNZZ032) .

Notes.

Three isolates representing D. camelliae-oleiferae cluster in a well-supported clade (ML/BI=100/1) and appear most closely related to D. pandanicola on Pandanus sp. and D. viniferae on Vitis vinifera . Diaporthe camelliae-oleiferae can be distinguished from D. pandanicola based on ITS and tub2 loci (24/462 in ITS and 11/401 in tub2); from D. viniferae based on ITS, cal, tef1 and tub2 loci (13/453 in ITS, 42/448 in cal, 7/339 in tef1 and 26/402 in tub2). Morphologically, D. camelliae-oleiferae differs from D. viniferae in having shorter alpha conidia (5-6.5 μm vs. 5-8.3 μm) ( Manawasinghe et al. 2019); from D. pandanicola in having narrower alpha conidia (1.9-2.3 μm vs. 2.5-3.2 μm) ( Huang et al. 2021).

Figures

Figure 2. Diaporthe camelliae-oleiferae (HNZZ 027) A Culture on PDA B conidiomata C conidiogenous cells D-F alpha and beta conidia. Scale bars: 200 μm (B); 10 μm (C-D); 20 μm (E, F).