Alternaria Spp. (alternaria + spp)

Distribution by Scientific Domains


Selected Abstracts


Alternaria spp.: from general saprophyte to specific parasite

MOLECULAR PLANT PATHOLOGY, Issue 4 2003
Bart P. H. J. Thomma
SUMMARY Alternaria species are mainly saprophytic fungi. However, some species have acquired pathogenic capacities collectively causing disease over a broad host range. This review summarizes the knowledge on pathogenic strategies employed by the fungus to plunder the host. Furthermore, strategies employed by potential host plants in order to ward off an attack are discussed. Taxonomy:Alternaria spp. kingdom Fungi, subkingdom Eumycotera, phylum Fungi Imperfecti (a non-phylogenetic or artificial phylum of fungi without known sexual stages whose members may or may not be related; taxonomy does not reflect relationships), form class Hypomycetes, Form order Moniliales, form family Dematiaceae, genus Alternaria. Some species of Alternaria are the asexual anamorph of the ascomycete Pleospora while others are speculated to be anamorphs of Leptosphaeria. Host Range: Most Alternaria species are common saprophytes that derive energy as a result of cellulytic activity and are found in a variety of habitats as ubiquitous agents of decay. Some species are plant pathogens that cause a range of economically important diseases like stem cancer, leaf blight or leaf spot on a large variety of crops. Latent infections can occur and result in post-harvest diseases or damping-off in case of infected seed. Useful Website: [source]


Onychomycosis caused by Alternaria spp. in Tuscany, Italy from 1985 to 1999

MYCOSES, Issue 3-4 2001
C. Romano
Alternaria alternata; Alternaria chlamidospora; Nagelinfektionen; Itraconazol. Summary. Cutaneous phaeohyphomycosis due to Alternaria spp. is reported with increasing frequency, especially in patients with immune deficiency. Onychomycosis caused by this mould is still rarely observed. Here we report nine cases observed in Tuscany in the period 1985,99; the agent was Alternaria alternata in eight cases and Alternaria chlamidospora in one. Diagnosis was made on the basis of repeated direct microscopic mycological examination and culture, confirmed by scanning electron microscope observation of fragments of colonies. In most cases, the clinical manifestations were dystropy and distal subungual hyperkeratosis of one or two nails of the feet or hands. Seven cases were treated with oral itraconazole, successfully in six cases, as clinical and mycological recovery was confirmed at follow-up 1 year later. Zusammenfassung. Kutane Phaeohyphomykosen durch Alternaria spp. werden immer häufiger beschrieben, besonders bei Patienten mit gestörter Infektabwehr. Andererseits sind Onychomykosen durch diese Pilzerreger nur selten zu beobachten. Wir berichten über 9 Fälle von Onychomykosen durch Alternaria spp., die innerhalb eines Zeitraums von 14 Jahren (1985,99) beobachtet worden sind. In 8 Fällen wurde Alternaria alternata und in einem Fall Alternaria chlamidospora isoliert. Die Diagnose wurde nach wiederholtem Nachweis der selben Spezies sowohl in Nativpräparaten als auch in Kultur gestellt und durch elektromikroskopische Untersuchungen der Kolonien bestätigt. Klinisch waren in den meisten Fällen dystrophische Veränderungen und distale subunguale Onychomykose an einem oder mehreren Finger- oder Fußnägeln zu beobachten. 7 Patienten wurden systemisch mit Itraconazol behandelt. In 6 dieser Fälle wurde eine klinische und mykologische Heilung erzielt. Während einjähriger Nachbeobachtungzeit blieben die Patienten rezidivfrei. [source]


Cutaneous alternariosis in a cardiac transplant recipient

AUSTRALASIAN JOURNAL OF DERMATOLOGY, Issue 1 2001
Tanya K Gilmour
SUMMARY A 55-year-old male cardiac transplant recipient presented with cutaneous nodules on the limbs caused by Alternaria alternata. Oral fluconazole 200 mg daily for 3 weeks was ineffective. Itraconazole 100 mg oral daily was ceased when hyperglycaemia developed. Individual lesions were successfully treated with either curettage and cautery or double freeze-thaw cryotherapy. Alternaria spp. are ubiquitous fungal saprophytes which may cause cutaneous infections particularly in immunocompromised patients. [source]


Studies on Colletotrichum acutatum and Greeneria uvicola: Two fungi associated with bunch rot of grapes in sub-tropical Australia

AUSTRALIAN JOURNAL OF GRAPE AND WINE RESEARCH, Issue 1 2007
CHRISTOPHER C. STEEL
Abstract Vineyards in the Hunter Valley and Hastings Valley (sub-tropical NSW) were examined by unaided eye for visible symptoms of bunch rot diseases at berry maturity in 2003 (for a total of five varieties over seven vineyards). Grey mould (Botrytis cinerea) was evident in three vineyards, and ripe rot (Colletotrichum acutatum) was evident in four of those seven vineyards surveyed. Other bunch rots at six of the vineyards could not be readily identified by visual inspection. The incidence of fungi on grapevine reproductive structures (and potentially bunch-rot fungi) was then recorded for a Cabernet Sauvignon vineyard in the Hastings Valley during the 2004/5 and 2005/6 growing seasons, and outcomes are reported here in some detail. By berry maturity, C. acutatum and Greeneria uvicola (bitter rot) were the predominant pathogens isolated from those structures, and constitute the first such report of bitter rot fungi on wine grapes in Australia. Indeed, the frequency of latent infection by C. acutatum and G. uvicola increased with berry development during the growing season. Other fungi isolated included Alternaria spp., Botryosphaeria spp., Cladosporium spp., Epicoccum sp., Fusarium spp., Nigrospora spp., Pestalotia spp., Phomopsis viticola and Trichoderma spp. Isolation of B. cinerea from this vineyard was rare. Infection of various wine grape varieties in vitro with C. acutatum and G. uvicola at post veraison revealed all varieties to be susceptible over a range of temperatures (20,35oC). Based on laboratory studies, there was no infection of berries at a relative humidity (RH) < 50%, and infection diminished at 87% RH. Infection did occur if the berries were first incubated at 100% RH for 24 hours, and then transferred to an environment of lower humidity. [source]