Nothophoma quercina
Nothophoma quercina (Syd. & P. Syd.) Qian Chen & L. Cai, in Chen, Jiang, Zhang, Cai & Crous, Stud. Mycol. 82: 213 (2015)
Index Fungorum number: IF 814086; Facesofungi number: FoF 2688
Basionym: Cicinobolus quercinus Syd., Ann. Mycol. 13:42 (1915)
=Ampelomyces quercinus (Syd.) Rudakov, Mikol.Fitopatol. 13: 109 (1979).
=Phoma fungicola Aveskamp et al., Stud. Mycol. 65:26 (2010)
Saprobic on dead branch of Ulmus hollandica Mill. Sexual morph: Undetermined. Asexual morph Conidiomata produced on surface of culture in PDA, 0.22–0.43 mm (x̄ = 0.28 mm, n = 10) diam., pycnidial, solitary, scattered, globose to irregularly-shaped, black, ostiolate. Pycnidia multi-layered, composed of pale brown, pseudoparenchymatous cells, with thick outer layer and thin inner layer. Conidiogenous cells phialidic, hyaline, simple, doliiform to ampulliform, variable in size. Conidia 2–5.5 × 1–4 μm (x̄ = 3.5 × 2.5 μm, n = 40), variable in size and shape, subglobose to oval or obtuse, initially hyaline, but brown at maturity, aseptate, smooth-walled. Conidial exudates not recorded.
Culture characteristics: Colonies on PDA reaching 80 mm diam. after 7 days at 25 °C, with regular margin, dull white aerial mycelium, surface floccose to downy, greenish-olivaceous to olivaceous near the centre and reverse dark ochreous in the centre and white at the margin.
Material examined: ITALY, Forlı`-Cesena Province, San Lorenzo in Noceto—Forlı`, on dead branch of Ulmus hollandica (Ulmaceae), 31 March 2016, Erio Camporesi (MFLU 16-2676, new host record), living culture, MFLUCC 16-1392, KUMCC 16-0128.
GenBank Numbers: LSU:KY053897, ITS:KY053896; RPB2, KY053898, b-tubulin: KY053899.
Notes: Nothophoma quercina has been reported as a saprobe from Quercus sp. in Ukraine (Aveskamp et al. 2010, Chen et al. 2015) and as a pathogen causing stem canker and fruit blight on Pistacia vera L. in the USA (Chen et al. 2013). This is the first record of N. quercina on Ulmus species. When comparing our species with the type specimen of N. quercina (CBS 633.92), they are similar in morphology, but differ in their host. The conidiomata are larger, while conidia are smaller compared to the type specimen. Based on our phylogenetic analysis of combined ITS, TEF1, b-tubulin and RPB2 sequence data of Nothophoma species, our strain (MFLUCC 16-1392) clustered with the ex-type strain of Nothophoma quercina with relatively high bootstrap and Bayesian probabilities (99%MP/1.00BYPP). (Tibpromma et al. 2017).
Figure x. Nothophoma quercina (MFLU 16-2676). a, b Conidiomata on the host tissue. c Pycnidia on PDA. d Section of pycnidial wall. e Conidiogenous cells. f Conidia. Scale bars a = 1 mm, b = 0.2 mm, c = 2 mm, d–f = 20 μm.
References:
Tibpromma S, Hyde KD, Jeewon R, Maharachchikumbura SS et al. 2017 – Fungal diversity notes 491–602: taxonomic and phylogenetic contributions to fungal taxa. Fungal diversity 83, 1-261.
Last update: 02 July 2021