Dichotomophthora portulacae Mehrl. & Fitzp. ex M.B. Ellis, Dematiaceous Hyphomycetes (Kew): 388 (1971).
Index Fungorum number: IF 312 976; Facesoffungi number: FoF 11664, Fig. 1
Description: see Ellis (1971) and Marin-Felix et al. (2019).
Material examined: see Ellis (1971) and Marin-Felix et al. (2019).
Figure. 1. Dichotomophthora basella (CPC 33016, ex-type, re-drawn from Fig. 14 in Marin-Felix et al., 2019). a, b Conidiogenous cells. c Conidiophores and conidia. d Conidia. e Microconidia. Scale bars = 10 μm.
Importance and role
Importance of genus to ecosystem
Species of Dichotomophthora are saprobic and helps in decomposition of organic matter in the ecosystem. Some taxa are pathogenic causing leaf spot and abscission (Soares & Nechet, 2017).
Industrial relevance and applications
Dichotomophthora is useful for agricultural industry as it can act as a biocontrol agent against several pathogens. Dichotomophthora indica is a pathogen of Myrtillocactus geometrizans and Gymmcalycium mihanovichii var. friedrichii in Arizona (Pfeiffer & Wheeler, 1989). D. portulacae is a biocontrol agent of common purslane (Klisiewicz, 1985).
Dichotomophthora is of quarantine importance they are mainly plant pathogen causing disease. For example, D. portulacae causes black stem rot on Purslane in Texas (Mitchell, 1986). D. portulacae also causes human keratitis was also reported from subtropical Africa (de Hoog et al.,. 2000).
Biochemical importance of the genus, chemical diversity or applications
Hosoe et al. (1990) reported Demethylmacrosporin (1,3,7-trihydroxy-6-methylanthraquinone), macrosporin, tetrahydroanthraquinones, altersolanols A and B, and ergosterol from Dichotomophthora lutea (Dactylaria lutea) in Japan. Alves et al. (2020) reported that the extract of a Dichotomophthora sp. has been reported to show activity against HCT-116 and PC-3 and can inhibit the AChE enzyme.
Diversity of the genus
Dichotomophthora comprises five species known on Gymnocalycium mihanovichii var. friedrichii (Cactaceae), Myrtillocactus geometrizans (Cactaceae), Portulaca oleracea (Stem blight.) (Portulacaceae), Beta vulgaris (Amaranthaceae), Pinus radiata (Pinaceae), Portulaca oleracea (Portulacaceae), Nicotiana glauca (Solanaceae), Anredera cordifolia (Basellaceae), Beta vulgaris (Amaranthaceae), Opuntia sp. (Cactaceae), Portulaca oleracea (Leaf necrosis) (Portulacaceae), Zygocactus truncatus (Tip blight) (Cactaceae) amongst others. Dichotomophthora is reported in Arizona, Brazil, Cuba, Florida, India, Iran, Italy, Malaysia, Netherlands, Thailand, United States, Virginia, West Indies amongst others. Dichotomophthora
may comprise many more species that awaits discovery.