Reinstatement and phylogenetic allocation of the palm rust genus Cerradoa in the Pucciniaceae, and establishment of Pseudocerradoa, gen. nov.

The genus Cerradoa (type species Cerradoa palmaea) was established in 1978 by Hennen and Ono and named after the Brazilian Cerrado biome. The holotype collected in Planaltina, Federal District, Brazil, belonged to the first rust fungus reported on palms (Arecaceae). For decades, the status of Cerradoa as a distinct genus has been regarded as doubtful, representing a synonym of Edythea (Uropyxidaceae) starting with the second edition of the Illustrated Genera of Rust Fungi in 1983. Our molecular phylogenetic analyses, as well as our morphological investigations, allowed us to reject this synonymy, leading to the reinstatement of Cerradoa within the Pucciniaceae. Cerradoa, together with morphologically similar genera such as the newly established Pseudocerradoa with two species (Ps. paullula and Ps. rhaphidophorae) infecting araceous hosts, the fern rust Desmella, and also P. engleriana, could not be assigned to any of the seven identified major lineages within the Pucciniaceae. Edythea, instead of being maintained as a member of the Uropyxidaceae, was herein placed in Pucciniaceae, shown phylogenetically in close relationship to Cumminsiella mirabilissima, both infecting the Berberidaceae. Additionally, our extensive phylogenetic analyses add guidance for future taxonomic revisions in the highly polyphyletic genus Puccinia and other established taxa within the family Pucciniaceae.

Cryptococcus depauperatus, a close relative of the human-pathogen C. neoformans, associated with coffee leaf rust (Hemileia vastatrix) in Cameroon.

The genus Cryptococcus is well known for its two species -Cryptococcus neoformans and C. gatii- that are etiological agents of cryptococcosis, an important fungal disease of mammals, including humans, and which is particularly common in immunocompromised patients. Nevertheless, Cryptococcus is a large and widely distributed genus of basidiomycetes occupying a broad range of niches, including mycoparasitism. One such mycoparasitic species is Cryptococcus depauperatus, which was firstly mistakenly described as a pathogen of scale insects under the name Aspergillus depauperatus. The "Aspergillus" conidiophores were later shown to be basidia of a Cryptococcus and the new combination C. depauperatus was proposed. Additionally, instead of an entomopathogen, the fungus was found to be a mycoparasite growing on the entomopathogen Akanthomyces (Lecanicillium) lecanii. Recently, during surveys for mycoparasites of coffee leaf rust (Hemileia vastatrix) in the context of a biocontrol project, white colonies covering rust pustules were observed in Cameroon. Upon close examination, instead of a member of the "white colony forming complex" of Ascomycetes, commonly collected growing on H. vastatrix, such colonies were found to represent a basidiomycete fungus with basidia-bearing chains of basidiospores, typical of the genus Cryptococcus. Morphological and molecular evidence was generated supporting the identification of the fungus on rust pustules as C. depauperatus. This is the first record of C. depauperatus from Africa and of its association with coffee leaf rust.

New species and records of Trichoderma isolated as mycoparasites and endophytes from cultivated and wild coffee in Africa.

A survey for species of the genus Trichoderma occurring as endophytes of Coffea, and as mycoparasites of coffee rusts (Hemileia), was undertaken in Africa; concentrating on Cameroon and Ethiopia. Ninety-four isolates of Trichoderma were obtained during this study: 76 as endophytes of healthy leaves, stems and berries and, 18 directly from colonized rust pustules. A phylogenetic analysis of all isolates used a combination of three genes: translation elongation factor-1α (tef1), rpb2 and cal for selected isolates. GCPSR criteria were used for the recognition of species; supported by morphological and cultural characters. The results reveal a previously unrecorded diversity of Trichoderma species endophytic in both wild and cultivated Coffea, and mycoparasitic on Hemileia rusts. Sixteen species were delimited, including four novel taxa which are described herein: T. botryosum, T. caeruloviride, T. lentissimum and T. pseudopyramidale. Two of these new species, T. botryosum and T. pseudopyramidale, constituted over 60% of the total isolations, predominantly from wild C. arabica in Ethiopian cloud forest. In sharp contrast, not a single isolate of Trichoderma was obtained using the same isolation protocol during a survey of coffee in four Brazilian states, suggesting the existence of a 'Trichoderma void' in the endophyte mycobiota of coffee outside of Africa. The potential use of these African Trichoderma isolates in classical biological control, either as endophytic bodyguards-to protect coffee plants from Hemileia vastatrix, the fungus causing coffee leaf rust (CLR)-or to reduce its impact through mycoparasitism, is discussed, with reference to the on-going CLR crisis in Central America.