Diaporthe acerigena C.M. Tian & Q. Yang

Yang, Qin, Fan, Xin-Lei, Guarnaccia, Vladimiro & Tian, Cheng-Ming, 2018, High diversity of Diaporthe species associated with dieback diseases in China, with twelve new species described, MycoKeys 39, pp. 97-149 : 97

Diaporthe acerigena C.M. Tian & Q. Yang sp. nov. Figure 3

Diagnosis.

Diaporthe acerigena can be distinguished from the phylogenetically closely related species D. oraccinii in larger alpha conidia.

Holotype.

CHINA. Shaanxi Province: Qinling Mountain, on symptomatic twigs of Acer tataricum , 27 June 2017, N. Jiang (holotype: BJFC-S1466; ex-type culture: CFCC 52554).

Etymology.

Named after the host genus on which it was collected, Acer .

Description.

On PDA: Conidiomata pycnidial, globose, solitary or aggregated, deeply embedded in the medium, erumpent, dark brown to black, 185-270 μm diam, whitish translucent to cream conidial drops exuding from the ostioles. Conidiophores 14.5-17 × 1.4-2.9 μm, cylindrical, hyaline, phiailidic, branched, straight to sinuous. Alpha conidia 7-10 × 2.1-2.9 μm (av. = 8.6 × 2.5 μm, n = 30), aseptate, hyaline, ellipsoidal, rounded at one end, slightly apex at the other end, usually with two-guttulate. Beta conidia not observed.

Culture characters.

Cultures incubated on PDA at 25 °C in darkness. Colony at first white, becoming dark brown in the centre with age. Aerial mycelium white, dense, fluffy, with cream conidial drops exuding from the ostioles.

Additional specimens examined.

CHINA. Shaanxi Province: Qinling Mountain, on symptomatic twigs of Acer tataricum , 27 June 2017, N. Jiang, living culture CFCC 52555 (BJFC-S1467).

Notes.

Two strains representing D. acerigena cluster in a well-supported clade and appear most closely related to D. oraccinii . Diaporthe acerigena can be distinguished from D. oraccinii based on ITS, his3, tef1 and tub2 loci (5/469 in ITS, 8/429 in his3, 8/326 in tef1 and 5/358 in tub2). Morphologically, D. acerigena differs from D. oraccinii in the longer and larger alpha conidia (8.6 × 2.5 vs. 6.6 × 1.9 μm) ( Gao et al. 2016).