Arthrinium arundinis (Corda) Dyko & B. Sutton, Mycotaxon

Thambugala, Kasun M., Hyde, Kevin D., Zhang, Jin-Feng & Liu, Zuo-Yi, 2018, Didymella eriobotryae sp. nov. (Didymellaceae) and Arthrinium arundinis (Apiosporaceae) from fruit of Eriobotrya japonica (loquat) in China, Phytotaxa 382 (1), pp. 136-147 : 140

Arthrinium arundinis (Corda) Dyko & B. Sutton, Mycotaxon 8: 119 (1979), Fig. 3

Basionym: Gymnosporium arundinis Corda, Icon. fung. 2: 1 (1838).

Associated with rotten loquat fruit ( Eriobotrya japonica (Thunb.) Lindl. ). Sexual morph Undetermined. Asexual morph Mycelium consisting of 2–5 μm diam., smooth, hyaline, branched, septate hyphae. Conidiophores reduced to conidiogenous cells. Conidiogenous cells 7–11 × 2–3.6 μm, arising from hyphae and aggregated in clusters on hyphae, hyaline, smooth, ampulliform. Conidia 5.3–7.7 × 5–7.4 μm (x = 6.5 × 6 μm, n = 60), brown to dark brown, smooth, globose in surface view, aseptate, lenticular in side view, with pale equatorial slit.

Culture characteristics:— Colonies growing on PDA, reaching a diameter of 60 mm after 5 d at 25 °C, circular to slightly irregular, flat to slightly raised, dense, surface white becoming grayish, reverse initially white to pale saffron becoming grayish, smooth surface with entire to slightly undulate edge.

Material examined:— CHINA, Guizhou province, from fruit of Eriobotrya japonica (Thunb.) Lindl. ( Rosaceae ), 20 June 2015, Kasun M. Thambugala CN 008–2 ( MFLU 16–2600); ibid. ( GZAAS 16–0027), living culture MFLUCC 16–0596 = GZCC 15–0037

Notes:— We describe the first report of Arthrinium arundinis from loquat ( Eriobotrya japonica ) fruit. Arthrinium arundinis is common on graminaceous hosts and has been also reported from a few non-graminaceous hosts ( Dyko & Sutton 1979, Crous & Groenewald 2013).

Didymellaceae Gruyter, Aveskamp & Verkley, Mycological Research 113 (4): 516 (2009)

Didymella Sacc., Michelia 2 (6): 57 (1880)

Notes:— The genus Didymella is characterized by having pseudothecial, immersed or erumpent, globose to flattened, ostiolate ascomata, 8-spored, bitunicate asci and mostly hyaline or brownish, ellipsoidal to cymbiform, uniseptate or multiseptate ascospores. The asexual morphs of Didymella is coelomycetous and pycnidial, ostiolate conidiomata phialidic, ampulliform or doliiform conidiogenous cells and aseptate, hyaline conidia which have variable shapes are emphasized as important characters to define the genus ( Aveskamp et al. 2010; Chen et al. 2015).

Figures

FIGURE 3. Arthrinium arundinis (MFLU 16–2600 and MFLUCC 16–0596) a, b. Symptoms on loquat fruit (Eriobotrya japonica). c. Colony on PDA. d. Conidiogenous cells giving rise to conidia. e, f. Conidia. Scale bars: d = 20 μm, e, f = 10 μm.