Data/hora: 09/06/2024 19:07:43

Provedor de dados: | Tropical Plant Pathology: fitopatologia brasileira
País: | Brazil
Título: | Genetic diversity among isolates of stemphylium solani from cotton
Autores: | MEHTA,Y.R.
Data: | 2001-12-01
Ano: | 2001
Palavras-chave: | Gossypium hirsutum; Lycopersicon esculentum; Stemphylium leaf blight; Molecular genetics; RAPD.
Resumo: | The fungus Stemphylium solani causes leaf blight of tomato (Lycopersicon esculentum) in Brazil. In recent years, severe epidemics of a new leaf blight of cotton (Gossipium hyrsutum) caused by S. solani occurred in three major cotton-growing Brazilian states (PR, MT and GO). Molecular analysis was performed to assess the genetic diversity among the S. solani isolates from cotton, and to verify their relationship with representative S. solani isolates from tomato. Random amplified polymorphic DNA (RAPD) markers and internal transcribed spacers of ribosomal DNA (rDNA) were used to compare 33 monosporic isolates of S. solani (28 from cotton and five from tomato). An isolate of Alternaria macrospora from cotton was also used for comparison. RAPD analysis showed the presence of polymorphism between the genera and the species. The A. macrospora and the S. solani isolates from cotton and tomato were distinct from each other, and fell into separate groups. Variation by geographic region was observed for the tomato isolates but not for the cotton isolates. Amplifications of the ITS region using the primer pair ITS4/ITS5 resulted in a single PCR product of approximately 600 bp for all the isolates. Similarly, when amplified fragments were digested with eight restriction enzymes, identical banding patterns were observed for all the isolates. Hence, rDNA analysis revealed no inter-generic or intra-specific variation. The genetic difference observed between the cotton and the tomato isolates provides evidence that S. solani attacking cotton in Brazil belongs to a distinct genotype.
Tipo: | Info:eu-repo/semantics/article
Idioma: | Inglês
Identificador: | http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-41582001000400002
Editor: | Sociedade Brasileira de Fitopatologia
Relação: | 10.1590/S0100-41582001000400002
Formato: | text/html
Fonte: | Fitopatologia Brasileira  v.26 n.4 2001
Fonte: | info:eu-repo/semantics/openAccess