Data/hora: 16/06/2024 19:16:21

Provedor de dados: 	102	
País: 	Brazil	
Título: 	Genotypic diversity among brazilian isolates of Macrophomina phaseolina revealed by RAPD	
Autores: 	Almeida,Álvaro M. R.; Abdelnoor,Ricardo V.; Arias,Carlos A. Arrabal; Carvalho,Valdemar P.; Jacoud Filho,David S.; Marin,Silvana R. R.; Benato,Luís C.; Pinto,Mauro C.; Carvalho,Cláudio G. P.	
Data: 	2003-06-01	
Ano: 	2003	
Palavras-chave: 	RAPD; ITS; PCR-RFLP; Soybean charcoal rot.	
Resumo: 	Macrophomina phaseolina has been considered one of the most prevalent soybean (Glycine max) pathogens in Brazil. No genetic resistance has been determined in soybean and very little is known about the genetic diversity of this pathogen in tropical and sub-tropical regions. Fifty-five isolates from soybean roots were collected in different regions and analyzed through RAPD for genetic diversity. The UPGMA cluster analysis for 74 loci scored permitted identification of three divergent groups with an average similarity of 99%, 92% and 88%, respectively. The three groups corresponded to 5.45%, 59.95% and 34.6%, respectively of all isolates used. A single plant had three different haplotypes, while 10.9% of the analyzed plants had two different haplotypes. In another study the genetic similarity was evaluated among isolates from different hosts [soybean, sorghum (Sorghum bicolor), sunflower (Helianthus annuus), cowpea (Vigna unguiculata), corn (Zea mays) and wheat (Triticum aestivum)] as well as two soil samples from native areas. Results showed that more divergent isolates originated from areas with a single crop. Isolates from areas with crop rotation were less divergent, showing high similarity values and consequently formed the largest group. Amplification of the ITS region using primers ITS1 and ITS4 produced only one DNA fragment of 620 bp. None of the isolates were differentiated through PCR-RFLP. Our results demonstrated genetic variability among Brazilian isolates of M. phaseolina and showed that one single root can harbor more than one haplotype. Moreover, cultivation with crop rotation tends to induce less specialization of the pathogen isolates. Knowledge of this variation may be useful in screening soybean genotypes for resistance to charcoal rot.	
Tipo: 	Info:eu-repo/semantics/article	
Idioma: 	Inglês	
Identificador: 	http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-41582003000300009	
Editor: 	Sociedade Brasileira de Fitopatologia	
Relação: 	10.1590/S0100-41582003000300009	
Formato: 	text/html	
Fonte: 	Fitopatologia Brasileira  v.28 n.3 2003	
Fonte: 	info:eu-repo/semantics/openAccess