Diaporthe hongkongensis R.R. Gomes, Glienke, Crous, Persoonia 31: 23. (2013)

Huang, Shengting, Xia, Jiwen, Zhang, Xiuguo & Sun, Wenxiu, 2021, Morphological and phylogenetic analyses reveal three new species of Diaporthe from Yunnan, China, MycoKeys 78, pp. 49-77 : 49

Diaporthe hongkongensis R.R. Gomes, Glienke, Crous, Persoonia 31: 23. (2013) Figure 4

Description.

Asexual morph: Conidiomata pycnidial, subglobose or globose, solitary, black, erumpent, coated with white hyphae, thick-walled, exuding creamy conidial droplets from central ostioles. Conidiophores hyaline, smooth, septate, unbranched, densely aggregated, cylindrical or clavate, straight to sinuous, swollen at base, tapering towards apex, 32.0-42.0 × 2.0-2.9 μm. Conidiogenous cells 20.0-24.2 × 1.3-2.3 μm, phialidic, cylindrical, terminal, slightly tapering towards apex. Alpha conidia, hyaline, smooth, aseptate, ellipsoidal or oval, 0-2 guttulate, apex subobtuse, base subtruncate, 5.5-7.0 × 2.0-2.5 µm (mean = 6.2 × 2.2 μm, n = 20). Beta conidia hyaline, aseptate, filiform, hamate, tapering towards both ends, mostly J-shaped, 21.5-27.0 × 1.4-1.8 µm (mean = 25.6 × 1.3 μm, n = 20). Gamma conidia not observed. Sexual morph not observed.

Culture characteristics.

Cultures incubated on PDA at 25 °C in darkness, growth rate 19.0-21.5 mm diam/day, cottony, radial with abundant aerial mycelium, sparse at margin, with an obvious pale brown concentric ring of dense hyphae, white to grayish on surface with age, white to pale brown on the reverse side.

Specimens examined.

China, Yunnan Province: Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, 19 April 2019, S.T. Huang. On diseased leaves of Millettia reticulata ( Fabaceae ) HSAUP194.81, living culture SAUCC194.81; on diseased leaves of Camellia sinensis ( Theaceae ) HSAUP194.87, living culture SAUCC194.87.

Notes.

In the present study, two strains (SAUCC194.81 and SAUCC194.87) from symptomatic leaves of Millettia reticulata and Camellia sinensis were similar to Diaporthe hongkongensis (CGMCC 3.17102) ( Gomes et al. 2013) and D. salinicola (MFLU 18-0553) ( Dayarathne et al. 2020) based on DNA sequences data (Fig. 1 ). Morphologically, our strains were similar to Diaporthe hongkongensis , which was originally described with an asexual morph on fruits of Dichroa febrifuga in China, but the asexual morph of D. salinicola was undetermined. We therefore identify our strains as D. hongkongensis .

Figures

Figure 1. Phylogram of Diaporthe spp. based on combined sequence data of ITS, TUB, TEF, CAL and HIS genes. The ML and BI bootstrap support values above 50 % and 0.90 BYPP are shown at the first and second position, respectively. Strains marked with " * " are ex-type or ex-epitype. Codes referring to strains from the current study are written in red. Some branches were shortened to fit them to the page as indicated by two diagonal lines with the number of times a branch was shortened indicated.

Figure 4. Diaporthe hongkongensis (SAUCC 194.87) a diseased leaf of Camellia sinensis b, c surface and reverse of colony after 15 days on PDA d conidiomata e-g conidiophores and conidiogenous cells h beta conidia i alpha conidia. Scale bars: 10 μm (e-i).