Data/hora: 08/06/2024 11:20:32

Biblioteca(s): 	Embrapa Soja.	
Data corrente: 	23/04/2012	
Data da última atualização: 	15/02/2013	
Autoria: 	TORRES, A. R.; KASCHUK, G.; SARIDAKIS, G. P.; SARIDAKIS, G.; HUNGRIA, M.	
Afiliação: 	ADALGISA RIBEIRO TORRES, CNPSo; GLACIELA KASCHUK, Universidade Paranaense; GEORGE P. SARIDAKIS, CNPSo; GEORGE P. SARIDAKIS, CNPSo; MARIANGELA HUNGRIA DA CUNHA, CNPSO.	
Título: 	Genetic variability in Bradyrhizobium japonicum strains nodulating soybean [Glycine max (L.) Merrill].	
Ano de publicação: 	2012	
Fonte/Imprenta: 	World Journal of Microbiology and Biotechnology, v. 28, n. 4, p. 1831-1835, Apr. 2012.	
Idioma: 	Português	
Conteúdo: 	Brazil has succeeded in sustaining production of soybean [Glycine max (L.) Merrill] by relying mainly on symbiotic N2 fixation, thanks to the selection and use in inoculants of very effective strains of Bradyrhizobium japonicum and Bradyrhizobium elkanii. It is desirable that rhizobial strains used in inoculants have stable genetic and physiological traits, but experience confirms that rhizobial strains nodulating soybean often lose competitiveness in the field. In this study, soybean cultivar BR 16 was singleinoculated with four B. japonicum strains (CIAT 88, CIAT 89, CIAT 104 and CIAT 105) under aseptic conditions. Forty colonies were isolated from nodules produced by each strain. The progenitor strains, the isolates and four other commercially recommended strains were applied separately to the same cultivar under controlled greenhouse conditions. We observed significant variability in nodulation, shoot dry weight, shoot total N, nodule efficiency (total N mass over nodule mass) and BOX-PCR fingerprinting profiles between variant and progenitor strains. Some variant strains resulted in significantly larger responses in terms of shoot total N, dry weight and nodule efficiency, when compared to their progenitor strain. These results highlight the need for intermittent evaluation of stock bacterial cultures to guarantee effective symbiosis after inoculation. Most importantly, it indicates that it is possible to improve symbiotic effectiveness by screening rhizobial strains for higher N2 fixation capacity within the natural variability that can be found within each progenitor strain.	
Thesagro: 	Fixação de Nitrogênio.	
Categoria do assunto: 	--	
Registro original: 	Embrapa Soja (CNPSO)	
Exemplares: 	CNPSO - (33012-1) - UPC - AP - PP - 12046 -  - 12046 - DIS