Plectosphaerella Kleb., Phytopath. Z. 1: 43 (1929)
Hypocreomycetidae, Glomerellales, Plectosphaerellaceae, Plectosphaerella
Saprobic on dead plant material, in soil or pathogenic on plants affecting root and collar rots. Sexual morph: Ascomata pale brown to dark brown, perithecial, superficial, subglobose to pyriform, thin-walled, with elongated neck. Peridium multi-layered, comprising dark brown cells of textura angularis. Paraphyses visible in young stages or absent. Asci hyaline, 8-spored, unitunicate, clavate, without an apical ring. Ascospores irregularly arranged, fusiform, rounded ends, 1–2-celled, wall asperulate. Asexual morph: Hyphomycetous. Conidiophores hyaline or centrally pale brown or pale olivaceous, lonely, sometimes branched, apical or lateral with verticillate or single conidiogenous. Conidiogenous cells hyaline, phialidic, determinate, discrete, thin-walled, smooth. Conidia hyaline, aggregated in slimy heads, bilaterally symmetric, oblong-ellipsoidal, slightly curved, aseptate to 1-septate, smooth-walled (adapted from Maharachchikumbura et al. 2016).
Type species: Plectosphaerella cucumeris Kleb., Phytopath. Z. 1: 43 (1929)
Notes: Plectosphaerella was introduced by Klebahn in 1929 (Palm et al. 1995). The type species is Plectosphaerella cucumerina, a holomorphic fungus (Zare et al. 2007, Carlucci et al. 2012). Plectosphaerella can be distinguished from other taxa by its asexual morph with the ratio of septate conidia, conidial shape and dimensions and presence or absence of chlamydospores (Carlucci et al. 2012).
Species illustrated in this entry
Plectosphaerella cucumerina (Lindf.) W. Gams, in Domsch & Gams
Carlucci A, Raimondo ML, Santos J, Phillips AJL. 2012 – Plectosphaerella species associated with root and collar rots of horticultural crops in southern Italy. Persoonia Molecular Phylogeny and Evolution of Fungi 28, 34
Maharachchikumbura SSN, Hyde KD, Jones EBG, McKenzie EHC et al. 2016 – Families of Sordariomycetes. Fungal Diversity 79, 1–317
Palm ME, Gams W, Nirenberg HI. 1995 – Plectosporium, a new genus for Fusarium tabacinum, the anamorph of Plectosphaerella cucumerina. Mycologia 397–406
Zare R, Gams W, Starink-Willemse M, Summerbell RC. 2007 – Gibellulopsis, a suitable genus for Verticillium nigrescens, and Musicillium, a new genus for V. theobromae. Nova Hedwigia 85, 463–489