Botryosphaeriales » Botryosphaeriaceae » Lasiodiplodia

Lasiodiplodia theobromae

Lasiodiplodia theobromae (Pat.) Griffon & Maubl., Bull. trimest. Soc. Mycol. Fr. 25: 57


Botryodiplodia theobromae Pat., Bull. Soc. Mycol. Fr. 8: 136 (1892).

= Diplodia gossypina Cooke, Grevillea 7: 95 (1879). (Figs 2-11)


Description: Conidiomata formed on poplar twigs in culture pycnidial, uniloculate, dark brown to black, immersed in the host becoming erumpent when mature. Paraphyses hyaline, cylindrical, septate, occasionally branched, ends rounded, up to 55 µm long, 3-4 µm wide. Conidiogenous cells hyaline, thin-walled, smooth, cylindrical, holoblastic, proliferating percurrently to form one or two annellations, or proliferating at the same level giving rise to periclinal thickenings. Conidia subovoid to ellipsoid-ovoid, apex broadly rounded, tapering to truncate base, widest in middle to upper third, thick-walled, contents granular, initially hyaline and aseptate, remaining hyaline for a long time, finally becoming dark brown and one-septate but only after discharge from the pycnidia, with melanin deposits on the inner surface of the wall arranged longitudinally giving a striate appearance to the conidia, (19-)21-31(-32.5) × (12-)13-15.5(-18.5) µm, 95% confidence interval = 26.2-27 × 14-14.4 µm ( ± S.D. = 26.2 ± 2.6 × 14.2 ± 1.2 µm, l/w ratio = 1.9 ± 0.2).


Notes: The connection between L. theobromae and its teleomorph has not been proven absolutely. Stevens (1925) made single ascospore cultures from a fungus he referred to as Physalospora gossypina on cotton stems in Florida, and from Hicoria, Ilex, Liquidambar, Quercus and Vitis. In all cases the conidia formed in these cultures were morphologically identical to those of L. theobromae. Stevens (1926) then determined that the fungus he called P. gossypina was in fact the same as Physalospora rhodina Cooke, which was later

transferred by von Arx (1970) to Botryosphaeria as B. rhodina (Cooke) Arx. However, there have been no subsequent reports to confirm this connection.