Data/hora: 26/05/2024 20:18:09

Biblioteca(s): 	Embrapa Cerrados; Embrapa Meio Ambiente.	
Data corrente: 	22/12/1993	
Data da última atualização: 	26/01/2000	
Autoria: 	PIEROBOM, C. R.	
Título: 	Studies on pycnidial and ascocarpic fungi which cause leaf spots on wheat in Washington.	
Ano de publicação: 	1983	
Fonte/Imprenta: 	Washington, DC: State University, 1983.	
Páginas: 	85p.	
Idioma: 	Inglês	
Notas: 	Ph.D. Dissertation.	
Conteúdo: 	A survey on pycnidium- and pseudothecium-producing fugi on wheat leaves was conducted in Washington, in 1980-82. Of extracted fruiting bodies, 47,7% were Septoria tritici, 29.2% were Mycosphaerella and Didymella species combined, 12% Ascochyta ssp., 6,2% Septoria nodorum, 1.2% Leptosphaeria species. Selenophoma donacis and Septoria avenae triticae were present in less than 1%. Of the total examined, 28.0% remain unidentified. Isolation of ascospores ejected from wheat leaves placed in humid chambers allowed the identification of some of the ascomycetes encountered. The Leptosphaeria species were divided into ten groups, on ascospore size and septation. Of these, only Leptosphaeria avenaria triticea and L. eustomoides could be identified since their anamorphs were obtained from single ascopore cultures. The remaining groups, not matching any description or matching more than one description in the literature, could not be identified with confidence. In the didymosporous group, Didymella exitialis, Micosphaerella tassiana and M. graminicola were identified. Didymella exitialis, the telemorph of Ascochyta sp., not previously reported on wheat in Washington occurs abundantly and requires further studies. Mycosphaerella graminicola, the telemorph of Septoria tritici, is rarely found on wheat leaves at harvest stage, but occurs with relative frequency in one year old stubble. Septoria species morphologically similar to S. tritici were found on the dicotyledonnous Stellaria media, Matricaria matricarioides and Lamium amplexicaule, all common wheat fields weeds. Cross-pathogenicity tests and cultural studies revealed several differences among these species and S. tritici, notwithstanding their capability of infect stressed wheat plants.Of the several culture media tested, sterilized corn leaves placed on water agar proved to be an excellent medium for identification and increase of inoculum of both pycnidial and ascocarpic inhabitants of cereal leaves.	
Palavras-Chave: 	Ascochyta spp; Didymella exitialis; Disease; Fungal diseases; Leptosphaeria avenaria triticea; Leptosphaeria eustomoides; Mycosphaerella tassiana; Plant diseases; Pseudothecium; Pycnidium; Selenophoma donacis; Septoria avenae triticea; Wheats.	
Thesagro: 	Doença de Planta; Doença Fúngica; Folha; Fungo; Septoria Nodorum; Septoria Tritici; Trigo; Triticum Aestivum.	
Thesaurus Nal: 	fungi; Lamium amplexicaule; leaves; Matricaria matricarioides; Mycosphaerella graminicola; Stellaria media; wheat.	
Categoria do assunto: 	--	
Registro original: 	Embrapa Cerrados (CPAC)	
Exemplares: 	CNPMA - (457-1) - ADD - TS - PP - 0208 -  - 1983.00208 - DIS
CPAC - (20176-1) - ADD - TS - -- - T048/83 - PIE - T048/83 - DIS