Data/hora: 23/09/2024 21:59:07

Biblioteca(s): 	Embrapa Agrobiologia.	
Data corrente: 	15/03/1999	
Data da última atualização: 	15/03/1999	
Autoria: 	XAVIER, G. R.; MARTINS, L. M. V.; NEVES, Maria Cristina P.; RUMJANEK, Norma G.	
Título: 	Heat tolerant strains of cowpea rhizobia isolated from the North-East region of Brazil.	
Ano de publicação: 	1997	
Fonte/Imprenta: 	In: REUNIAO ANUAL DA SOCIEDADE BRASILEIRA DE BIOQUIMICA E BIOLOGIA MOLECULAR, 26., maio 1997, Caxambu. Resumos... Caxambu: Sociedade Brasileira de Bioquimica e Biologia Molecular, 1997. p.49.	
Idioma: 	Inglês	
Conteúdo: 	Temperature is a factor which limits growth, survival, competitiveness and population size of soil rhizobia and nitrogen-fixing activity when the bacteria are associated with leguminous roots. Thus, it is not surprising that rhizobia strains nodulating cowpea, which grows well in semi-arid areas showing high daily temperatures, are tolerant to these conditions. This study aims to select heat tolerant inoculants for cowpea growing in the north-east region of Brazil, from a collection of rhizobia that has already been characterized regarding other parameters, such as nodulation, efficiency, Hup phenotype and intrinsic antibiotic resistance. Seventy-eight isolates from a variety of soils were studied, which had been collected at both a semi-arid and tropical  rain forest areas located at the same latitude in the north-east region of Brazil. The assay was performed in YEM medium at 28 graus C, as a control, at 39 graus C and 42 graus C to determine heat tolerant strains. In this region, the fast-growing rhizobia population was significant and 96% of them were tolerant to 39 graus C, while only 63% of slow-growers were capable of developing under this condition. Thirty percent of isolates from the semi-arid region showed tolerance to 42 graus C againt 18% of the isolates from the tropical rain forest region. Comparing these results with the ones obtained for strains BR 96 and BR 29 (B. elkanii), BR 33 (B. japonicum) commonly used for soybean crops, and BR 2001 (Bradyrhizobium sp) recommended for cowpea, it was...    	
Palavras-Chave: 	Brasil; Isolation; Temperature resistance.	
Thesagro: 	Feijão de Corda; Isolamento; Resistência a Temperatura; Rhizobium.	
Thesaurus Nal: 	Brazil; cowpeas.	
Categoria do assunto: 	--	
Registro original: 	Embrapa Agrobiologia (CNPAB)	
Exemplares: 	CNPAB - (24375-1) - UPC - PL - -- -  -  - 22216 - DIS