Botryosphaeriales » Botryosphaeriaceae » Botryosphaeria

Botryosphaeria dothidea

Botryosphaeria dothidea (Moug.) Ces. & De Not., Comm. Soc. crittog. Ital. 1(fasc. 4): 212 (1863)

Saprobic on dead stems of host plant in terrestrial habitat. Sexual morph: see Phillips et al. (2013). Asexual morph: Conidiomata 100–2000 µm diam., 70–1000 µm high, black, stromatic, pycnidial, forming a botryose aggregate of up to 50, solitary to gregarious or confluent, immersed in origin, becoming erumpent, multi-locular, globose or ovoid to subglobose, thick-walled, glabrous, smooth, papillate, ostiolate. Ostiole circular to subcylindrical, centrally or laterally located. Conidiomatal wall 30–150 µm wide, composed of thick-walled, dark brown to hyaline cells of textura angularis to textura prismatica or textura globosa. Conidiophores formed from the inner cavity of the conidiomata, reduced to conidiogenous cells, or present, hyaline, cylindrical to subcylindrical. Conidiogenous cells 5–30 × 2–6 µm, hyaline, annelidic, phialidic or holoblastic, ampulliform to subcylindrical, integrated or determinate, smooth. Conidia 13–33 × 4–10 µm, hyaline, fusiform, with a rounded apex and a slightly narrow truncate base, straight or slightly curved, 0–1-septate, thick-walled, smooth, bearing irregular mucoid sheath at each or both ends or without sheath. Synasexual morph not known.

Culture characters: colonies on PDA, reaching 25–30 mm diam. after 14 d at 25°C, white at first, then olivaceous or dark brown, eventually black, circular, flattened, with aerial hyphae dense, filamentous, cottony, margins undulate to entire. reverse white at first, becoming black in the middle, and forming numerous conidiomata.

Material examined: Italy, province of Forlì-Cesena, Castrocaro Terme, Sorgara, on dead aerial branches of Ailanthus altissima (Simaroubaceae), 26 January 2016, Erio Camporesi, IT2795 (MFLU 16-0504), living culture MFLUCC 16-1304 = KUMCC 16-0077, (KUN, HKAS 97481); ibid., Predappio Alta, on dead aerial stems of Artemisia sp. (Asteraceae), 22 September 2012, Erio Camporesi, IT740 (MFLU 19-2877), living culture MFLUCC 13-0063 = ICMP 20781, (KUN, HKAS 93660); ibid., 7 April 2012, Erio Camporesi, IT217 (MFLU 19-2870), living culture MFLUCC 13-0199 = ICMP 20771 = KUMCC 15-0637, (KUN, HKAS 101687); ibid., Predappio, Rocca delle Caminate, on dead aerial stems of Torilis arvensis (Apiaceae), 2 March 2016, Erio Camporesi, IT2862S (MFLU 16-0936), living culture MFLUCC 16-1312 = ICMP 21536 = KUMCC 16-0084, (KUN, HKAS 101648); ibid., near Castrocaro, on dead aerial stems of Urtica dioica (Urticaceae), 19 September 2012, Erio Camporesi, IT734 (MFLU 19-2876), living culture MFLUCC 13-0206 = ICMP 20780 = KUMCC 15-0613, (KUN, HKAS93659); ibid., Province of Pesaro-Urbino, Monte Nerone, on dead aerial branches of Cornus sanguinea (Cornaceae), 11 June 2012, Erio Camporesi, IT428 (MFLU 19-2873), living culture MFLUCC 13-0202 = ICMP 20773 = KUMCC 15-0605, (KUN, HKAS 93653).

Notes: Botryosphaeria dothidea was associated with a wide range of host plant; the details are provided by Phillips et al. (2013), and will not be present here. The asexual morph of Botryosphaeria dothidea is variable in form and dimension of conidiomata, conidiogenous cells and conidia.

Botryosphaeria dothidea (a–e from MFLU 16-0504, f–h from MFLU 16-0936, i–k from MFLU 19-2870/IT217, l–m MFLU 19-2877/IT740) a–c, f, i, l Appearance of dark brown to black conidiomata on the host. d, g, j, m Vertical sections of conidiomata. e, h, k, n Section of peridium. Scale bars c = 500 µm, d = 200 µm, e, j = 50 µm, f, i = 200 µm, g, m = 100 µm, h, k, n = 20 µm.