Fitopatologia - Artigos

URI permanente para esta coleçãohttps://locus.ufv.br/handle/123456789/11741

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    The mycobiota of the weed Lantana camara in Brazil, with particular reference to biological control
    (Mycological Research, 1995-07) Barreto, Robert W.; Evans, Harry C.; Ellison, Carol A.
    A survey of the fungi associated with the tropical weed Lantana camara was conducted during 1988 and 1989 in part of its native range in southern Brazil. The sampling activity was concentrated mainly in the state of Rio de Janeiro, covering 70 sites located in different climatic or ecological zones. The survey continued and was extended to the Amazon and northeast regions. Nine fungal species were identified as members of the mycobiota, including the previously undescribed fungi: Ceratobasidium lantanae-camarae sp. nov., Dendryphiella aspera sp. nov. and Micropustulomyces mucilaginosus gen. et sp. nov. Perisporiopsis lantanae, which has not been recorded previously in Brazil, has its anamorph described for the first time. The rusts Aecidium lantanae were also recorded. Field observations suggest that several fungal pathogens have potential as classical biocontrol agents of the weed in the Old World tropics: Ceratobasidium lantanae-camarae and Puccinia lantanae in lowland humid climates; Mycovellosiella lantanae, Prospodium tuberculatum and Micropustulomyces mucilaginosus in more elevated or subtropical areas. In addition, databases and herbaria were consulted in order to compile a world list of fungal pathogens associated with L. camara.
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    The mycobiota of the weed Mikania micrantha in southern Brazil with particular reference to fungal pathogens for biological control
    (Mycological Research, 1995-03) Barreto, Robert Weingart; Evans, Harry Charles
    A survey of the fungi associated with the tropical weed Mikania micrantha was conducted during 1988 and 1989 in part of its native range in southern Brazil. Sampling was concentrated mainly in the state of Rio de Janeiro, covering 70 sites in different climatic or ecological zones. Nine species were identified, including the recently described downy mildew species Basidiophora montana and the previously undescribed Mycosphaerella mikania-micranthae sp. nov. with its anamorph Septoria mikania-micranthae. Asperisporium mikaniae comb. nov., Asperisporium mikaniigena comb. nov., Pseudocercospora plunketii comb. nov., and Cercospora mikaniacola are new records for Brazil. Field observations indicate that Basidiophora montana has potential as a classical biological control agent of the weed in Old World subtropical or montane climates, whilst Mycosphaerella mikania-micranthae and the microcyclic rust Puccinia spegazzinii appear to be equally damaging to the host but to have a wider climatic range and thus are highly promising agents for introduction throughout the Palaeotropics.
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    First record of Cercospora pistiae causing leaf spot of water lettuce ( Pistia stratioites ) in Brazil, with particular reference to weed biocontrol
    (Mycopathologia, 1998-11) Barreto, R. W.; Evans, H. C.; Hanada, R. E.
    Pistia stratioites , the water lettuce, is an important pantropical aquatic weed. It has been the target of successful classical biocontrol programmes utilizing an insect natural enemy collected in Brazil and introduced into Australia, Papua New Guinea and South Africa. Little attention was given to the fungal pathogens associated with this weed as potential biocontrol agents. An 11-month field survey in the state of Rio de Janeiro involving repeated visits to 12 sites, and a 2-month survey in the Amazonas Basin (Amazonas state) in Brazil, yielded only one pathogenic fungus on P. stratioites. This was identified as Cercospora pistiae. No previous record of this species has been made in Brazil nor in the New World. The fungus is described and its taxonomy and biocontrol potential discussed herein. C. pistiae is a damaging pathogen of water lettuce. Its distribution was restricted to two interconnected sites in Rio de Janeiro. A literature and herbaria survey yielded few fungi associated to water lettuce (8 species), probably reflecting a lack of adequate collection in the centre of origin of the plant.
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    Nimbya alternantherae and Cercospora alternantherae: two new records of fungal pathogens on Alternanthera philoxeroides (alligatorweed) in Brazil
    (Australasian Plant Pathology, 1999-06) Barreto, Robert W.; Torres, André N. L.
    Alternanthera philoxeroides is an amphibious herbaceous weed (alligatorweed) of the Amaranthaceae, and is a native of South America. It has become a very aggressive invader in many regions of the world. A preliminary survey for fungal pathogens to be used as biocontrol agents for this weed of five Brazilian States yielded two species, Nimbya alternantherae and Cercospora alternantherae. This is the first report of these species from Brazil. The pathogenicity of these fungi was tested against plants from Brazilian and Australian biotypes of A. philoxevoides. N. alternantherae was shown to be very damaging and appears to have biocontrol potential.