Cercospora berteroae and Pseudocercosporella gei , rare anamorphic fungi

The paper presents two species of hyphomycetous fungi, presumably Mycosphaerella anamorphs, recently collected in central and north-eastern Poland. Habit and morphology, illustrated with macro- and microphotographs, and worldwide distribution of the species are characterized. Both species have been collected in Poland for the first time.

The genus Cercospora was introduced by Fresenius in 1863 for the Passalora-like species with pluriseptate conidia (Crous, Braun 2003). Many members of the genus are important plant pathogens and often major agents of crop losses worldwide. They occur on a wide range of hosts and can be associated with angiosperms as well as with some gymnosperms and ferns (To-Anun, Hidayat, Meeboon 2011). Some species are hyperparasites of rust fungi, e.g., Passalora acori (J. M. Yen) U. Braun & Crous, parasitizing the uredospores of Uromyces sparganii Cooke & Peck (Shin, Kim 2001). According to the recent taxonomic studies of the Cercospora species in Thailand, the genus is considered to be monophyletic (To-Anun et al. 2011).
The members of the Pseudocercosporella genus are phytopathogens mostly causing leaf spots (Shin, Kim 2001). The genus was established by Deighton over one hundred years after Cercospora for the species characterized by unthickened, inconspicuous conidial scars. Later Braun (1990) narrowed the genus to species with solitary conidia and transferred the taxa with catenate conidia to Thedgonia. According to the molecular studies of Crous et al. (2012) the genus resides in a large clade together with Cercospora, Miuraea, Phloeospora, Septoria and Xenocercospora.
Despite the fact that many members of the Cercosporella/Ramularia complex are economically important pathogens of major agricultural crops this group of anamorphic fungi is still insufficiently known worldwide (Shin, Kim 2001;Bakhshi, Arzanlou, Babai-Ahari 2012;To-Anun et al. 2011). The recently published preliminary list of cercosporoid hyphomycetes known from Poland covers 32 species of the genus Cercospora and 31 belonging to Passalora (Świderska-Burek 2007). Lately, the number of cercosporoid fungi known in the country has been expanded with Passalora acericola (Liu & Guo) U. Braun & Crous (Świderska-Burek, Mułenko 2010). According to the checklist of Polish micromycetes only 6 Pseudocercosporella species have been noted in Poland so far (Świderska-Burek 2008).

MATERIAL AND METHODS
The original materials with plant organs affected by anamorphic fungi were collected in the urbicoenoses of Łódź city and a single specimen originates from Bie-Biebrza National Park. The fresh specimens mounted in lactophenol picric acid solution (Fluka) were examined using the microscope Nikon Eclipse E200; measurements of the morphological structures were made also in tap water. Microphotographs of morphological structures of the species were taken with a Nikon DS-F1 digital camera. The fungal nomenclature follows Crous and Braun (2003) and the host plants nomenclature is given after Mirek et al. (2002).
The vouchers are deposited in the Herbarium Universitatis Lodziensis (LOD) in the collection of parasitic fungi labelled as PF.

FINAL REMARKS
The presented findings of two new species for Poland were the result of studies carried out of in the Łódź city, the area greatly subjected to anthropopression. However, Cercospora berteroae has been also subsequently confirmed at the protected area in Biebrza National Park. Both fungal species were found on common plant species, which are often parasitized by other micromycetes in Poland (Mułenko, Majewski, Ruszkiewicz-Michalska 2008). On Berteroa incana only biotrophic parasites were recorded, e.g., Albugo candida (Pers.) Kuntze, Peronospora berteroae Gäum. and Erysiphe cruciferarum Opiz ex Junell. Geum urbanum is known to host Peronospora gei H. Syd., Sphaerotheca aphanis (Wallr.) U. Braun, and two species classically referred to as Mycosphaerella anamorphs (e.g., Ramularia gei (Elliasson) Lindr. and Septoria gei Roberge ex Desm.).
Although Cercospora and Pseudocercosporella have traditonally been linked to the ascomycetous genus Mycosphaerella s.l. (Crous, Braun 2003), the teleomorphs of the majority of cercosporoid fungi are still unknown and a Mycosphaerella state has been proven only for few species (Bakhshi et al. 2012). Both species reported here have no known teleomorphic connections. There are no Mycospharella taxa connected with Berteroa species (Aptroot 2006) while four species are known to be parasites of Geum: Sphaerella geicola Kalchbr. & Cooke, Mycospharella koldingensis Munk, M. larsenii Munk, and M. melanoplaca (Dem.) Johanson ex Oudem. However, none of them was reported in Poland so far (Mułenko et al. 2008). Thus, we assume that species represented by anamorphs reported here are new to Polish mycobiota.
Acknowledgements. The authors are very grateful to Professor Maria Ławrynowicz, Curator of the Fungal Collection of Herbarium Universitatis Lodziensis (LOD), for permission to analyse herbarium materials. They include specimens collected by Danuta Papierz and Aleksandra Ozimek (MSc students supervised by the second author) whose contribution is greatly acknowledged. We thank Professor Krystyna Czyżewska (University of Łódź) for providing access to microphotographic equipment as well as two anonymous reviewers for their thorough review of the paper and critical remarks. The studies were partially supported by the Ministry of Science and Higher Education (grant no N305 077 32/2708). The first author was also granted in the frame of the project "Scholarships to support innovative doctoral research" by the European Social Fund and the Budget as a part of Integrated Regional Operational Programme in 2010.