Diaporthe sambucusii C.M. Tian & Q. Yang, 2018

Yang, Qin, Du, Zhuo & Tian, Cheng-Ming, 2018, Phylogeny and morphology reveal two new species of Diaporthe from Traditional Chinese Medicine in Northeast China, Phytotaxa 336 (2), pp. 159-170 : 164-165

Diaporthe sambucusii C.M. Tian & Q. Yang , sp. nov. FIGURE 2 .

MycoBank no: MB823869

Holotype:— BJFC-S1368 .

Etymology:— sambucusii : named after the host genus, Sambucus .

Host/Distribution:—from Sambucus williamsii in northeast China.

Original description:—Sexual state: Undetermined. Asexual morph: Conidiomata pycnidial, conical to globose, embedded in bark, erumpent through the bark surface at maturity, dense, with a single locule. Ectostromatic disc (400–)425–575(−600) μm (av. = 500 μm, n = 20), brown to black, one ostiole per disc. Locule undivided, (480–)550–700(−800) μm (av. = 650 μm, n = 20) in diam. Wall parenchymatous, consisting 3–4 layers of medium brown textura angularis. Conidiophores hyaline, unbranched, phialides, cylindrical, ampulliform, (10–)11–15.5(−17.5) × (1.2–)1.4−1.8(−2.0) μm (av. = 13.5 × 1.6 μm, n = 50), straight or slightly curved. Conidiogenous cells hyaline, phialides, cylindrical, terminal, slightly tapering towards the apex, 0.5–1 μm diam. Paraphyses absent. Alpha conidia abundant in twigs, (6.0–)7.0–9.5(−10.5) × (1.8–)2.0−2.5(−2.6) μm (av. = 8.5 × 2.2 μm, n = 50), hyaline, aseptate, oval to fusiform, conspicuously biguttulate. Beta conidia (16.5–)18.5–23.5(−25.5) × 0.9–1.1 μm (av. = 21 × 1.0 μm, n = 50), hyaline, aseptate, smooth, filiform, straight or curved, eguttulate.

Culture characters:—Cultures incubated on PDA at 25 ° C in darkness, colony originally flat with white felty aerial mycelium, becoming yellowish-brown aerial mycelium at the centre and beige mycelium at the marginal area, hyphae dense with irregular margin, conidiomata sparse, irregularly distributed over agar surface.

Material examined:— CHINA, Heilogjiang Province, Yichun city, 46°41’56.95”N, 129°01’27.49”E, 373 m asl, on twigs and branches of Sambucus williamsii, Q. Yang and Z. Du , 27 July 2016 ( BJFC-S 1368, holotype; living ex-type culture, CFCC 51986). Heilongjiang Province, Yichun city, 46°41’56.85”N, 129°01’27.30”E, 370 m asl, on twigs and branches of Sambucus williamsii, Q. Yang and Z. Du , 27 July 2016 ( BJFC-S 1369, paratype; living culture, CFCC 51987).

Notes: — This new species is introduced as molecular data showed it to be distinct, and this is also supported by morphological traits. The phylogram clustered in 78 clades with 63 ex-type Diaporthe strains distinguished the new species with high support ( MP / ML / BI =100/100/1) ( Fig. 1 ). Morphologically, it is characterized by oval to subfusiform, aseptate, biguttulate alpha coidia and filiform, straight or curved, eguttulate beta conidia, which is similar with D. ganjae from Cannabis sativa and D. compacta from Camellia sinensis . However, Diaporthe sambucusii can be distinguished with D. ganjae in its smaller alpha conidia (7.0–9.5 × 2.0−2.5 μm in D. sambucusii vs. 5.0–11.5 × 2.0−4.0 μm in D. ganjae ) ( McPartland 1983); with D. compacta in its bigger alpha conidia (7.0–9.5 × 2.0−2.5 μm D. sambucusii vs. 6.0–7.5 × 2−3 μm in D. compacta ) ( Gao et al. 2017).

Figures

FIGURE 1. Phylogram of ITS regions based on MP, ML and Bayesian analysis. Values above the branches indicate maximum parsimony bootstrap (MP BP ≥ 50 %) and maximum likelihood bootstrap (ML BP ≥ 50 %). Values below branches represent posterior probabilities (BI PP ≥ 0.90) from Bayesian inference. Scale bar = 80 nucleotide substitutions. The new sequences resulting from the current study are in blue. Ex-type strains are in bold.

FIGURE 2. Morphology of Diaporthe Sambucusii from Sambucus williamsii (BJFC-S1368).A, B: Habit of conidiomata on branches. C: Transverse section of conidioma. D, E, G: Conidia. F: Conidiophores. H: Colonies on PDA at 30 days. Scale bars: B–C = 500 μm; D, G = 5 μm; E–F = 10 μm.