Magnaporthaceae P.F. Cannon, Syst. Ascom. 13(1): 26 (1994)
Index Fungorum number: IF81963; 135 species.
Pathogenic on monocotyledons or saprobic on plant material. Sexual morph: Ascomata perithecial, solitary or scattered, black, superficial or immersed in plant tissue, globose to subglobose, with cylindrical, black, periphysate neck. Peridium comprising a few to several layers of cells of textura epidermoidea. Paraphyses hyaline, septate, intermingled among asci. Asci 8-spored, unitunicate, subcylindrical, short-pedicellate, with an apical ring. Ascospores biseriate, hyaline to olivaceous, filiform or fusoid, curved to sigmoid, with or without transverse septate ends, bluntly rounded, lacking sheaths. Asexual morph: Hyphomycetous, at times formed from sclerotia. Conidiophores unbranched or branched. Conidiogenous cells integrated, pigmented, phialidic with collarettes, or denticulate. Conidia variable in shape, hyaline to pale brown, straight or curved, with or without septa (adapted from Maharachchikumbura et al. 2016b).
Type genus – Nakataea Hara
Notes – Magnaporthaceae was introduced by Cannon (1994). The placement of taxa of Magnaporthaceae has long been problematic due to the lack of convincing morphological and inconclusive molecular data (Thongkantha et al. 2009). Based on DNA phylogenies, Magnaporthaceae was placed as a family in the Sordariomycetes (Kirk et al. 2001, Lumbsch & Huhndorf 2007, Maharachchikumbura et al. 2016b). Thongkantha et al. (2009) established a new order, Magnaporthales to accommodate Magnaporthaceae based on characters and phylogenetic analysis. The family was originally described with six genera (Cannon 1994). Kirk et al. (2001) accepted nine genera while Kirk et al. (2008) accepted 13 genera. Luo et al. (2014) established Pseudophialophoda in the family. Maharachchikumbura et al. (2016b) provided an updated account with 22 genera and a key to species. A new genus, Bifusisporella was also introduced by Silva et al. (2009). In this study, we accept 23 genera in Magnaporthaceae based on publications and taxonomy.
Ecological and economic significance of Magnaporthaceae
Most genera of Magnaporthaceae are necrotrophic and hemibiotrophic plant pathogens infecting root and shoots of Poaceae and Cyperaceae (Zhang et al. 2011, Luo & Zhang 2013). Endophytic or apparently saprotrophic taxa on non-gramineous hosts were added by Tibpromma et al. (2018). Pyricularia oryzae (= Magnaporthe oryzae), a pathogen causing rice blast disease, was accommodated in Pyriculariaceae, while Magnaporthe salvinii which causes stem rot in rice was synonymized under Nakataea oryzae in Magnaporthaceae (Klaubauf et al. 2014). Other notable pathogens of Magnaporthaceae include Gaeumannomyces graminis, Magnaporthiopsis poae and M. rhizophila. Some members of Magnaporthaceae (e.g. Ophioceras and Ceratosphaeria) also occur in aquatic habitats, or on dead plant material, such as wood (Shearer et al. 1999, Réblová 2006, Huhndorf et al. 2008, Thongkantha et al. 2009).