Diaporthe betulae C.M. Tian & X.L. Fan, 2016

Du, Zhuo, Fan, Xin-Lei, Hyde, Kevin D., Yang, Qin, Liang, Ying-Mei & Tian, Cheng-Ming, 2016, Phylogeny and morphology reveal two new species of Diaporthe from Betula spp. in China, Phytotaxa 269 (2), pp. 90-102 : 96

Diaporthe betulae C.M. Tian & X.L. Fan , sp. nov. FIGURE 2 .

Fungal Names FN 570261; Facesoffungi FoF02174

Holotype:— BJFC-S1317 .

Etymology:— betulae , referring to Betula platyphylla , the host known for this species.

Host/Distribution:—from Betula platyphylla in China.

Original description:—Sexual morph: undetermined.Asexual morph: Conidiomatal stromata immersed, erumpent slightly from surface of host branches, separate, conical, with a single locule. Ectostromatic disc grey to black, with one ostiole per disc. Ostiole medium grey to black, up to the level of disc, (160–)170–220(–280) μm (av. = 250 μm, n = 20) diam. Locule undivided, conoid, (590–)600–1250(–1460) μm (av. = 1050 μm, n = 20) diam. Conidiophores reduced to conidiogenous cells. Conidiogenous cells hyaline, phialides, straight or slightly curved, with periclinal thickening present. Alpha conidia hyaline, ellipsoidal, aseptate, smooth, conspicuously biguttulate, 8.5–11(–11.5) × 3–4(–4.5) μm (av. = 10 × 3.5 μm, n = 50). Beta conidia absent.

Cultures:—Colony originally compact and flat with white aerial mycelium, then developing dark green to brown aerial mycelium at the centre and dark green mycelium at the marginal area, zonate with 4–5 well defined zones 0.5 cm wide with an irregular edge; conidiomata sparse, irregularly distributed over agar surface.

Material examined:— CHINA, Sichuan Province: Guangyuan City, Tianzhao Mountain, 32°29’22.79”N, 105°43’32.78”E, 1422 m asl, on twigs and branches of Betula platyphylla , coll. X. L. Fan, 28 April 2015 ( BJFC-S 1317, holotype), ex-type culture, CFCC 50469. Sichuan Province: Guangyuan City, Tianzhao Mountain, 32°29’21.49”N, 105°43’32.60”E, 1422 m asl, on twigs and branches of Betula platyphylla , coll. X. L. Fan, 28 April 2015 ( BJFC-S 1318, paratype), living culture, CFCC 50470.

Notes:—This new species is introduced as molecular data show it to be distinct clade with high support ( MP / ML / BI =100/100/1). Morphologically, it is characterized by ellipsoidal, aseptate, smooth alpha conidia, which are conspicuously biguttulate, which is similar with Diaporthe vaccinii from Vaccinium macrocarpon Aiton and V. oxycoccos L., with a geographic range in the USA ( Shear et al. 1931). However, Diaporthe betulae can be distinguished by its larger alpha conidia (8.5–11 × 3–4 μm, av. 10 × 3.5 μm vs. 6–11 × 2–4 μm, av. 8 × 3 μm) and dark green to brown colonies on PDA, as compared to the white to yellowish colonies in D. vaccinii ( Chao and Glawe 1985; Farr et al. 2002).

Figures

FIGURE 2. Morphology of Diaporthe betulae from Betula platyphylla (BJFC-S1317).A, B: Habit of conidiomata on twig. C: Transverse sections through conidiomata. D: Longitudinal sections through conidiomata. E: Conidiophores. F: Alpha conidia. G: Colonies on PDA at 3 days (left) and 30 days (right). Scale bars: B–D = 500 μm; E–F = 5 μm.