Data/hora: 23/09/2024 16:05:34

Biblioteca(s): 	Embrapa Arroz e Feijão; Embrapa Soja.	
Data corrente: 	15/04/1992	
Data da última atualização: 	17/04/2024	
Autoria: 	HUNGRIA, M.; RUSCHEL, A. P.	
Afiliação: 	MARIANGELA HUNGRIA DA CUNHA, CNPSO; ALAIDES PUPPIN RUSCHEL, CNPAF.	
Título: 	Acetylene reduction, hydrogen evolution and nodule respiration in Phaseolus vulgaris.	
Ano de publicação: 	1989	
Fonte/Imprenta: 	Biology and Fertility of Soils, v. 7, n. 4, p. 351-358, 1989.	
Idioma: 	Inglês	
Conteúdo: 	In an experiment performed under greenhouse conditions, four cultivars of Phaseolus vulgaris L. (Venezuela-350; Aroana; Moruna; Carioca) were inoculated with three Rhizobium leguminosarum biovar phaseoli strains (C-05; C-40 = CIAT 255; C-89 = CIAT 55) and were fertilized with an N-free mineral nutrient solution. The plants were harvested 25, 40, and 55 days after emergence and the following paramenters were evaluated: Nitrogenase activity of nodulated roots, H2 evolution by the nodules; relative efficiency of nitrogenase; respiration rates of nodulated roots and detached nodules; dry weight and total N of stems, leaves, pods, roots, and nodules. Generally the bean cultivar, Rhizobium strain, had an effect and there was an interaction effect with both symbiotic partners, on all parameters. On average, nodules represented 23% of total root respiration but the best symbiotic combinations showed lower ratios of C respired to N fixed. The maximum N-assimilation rate (between 40 and 55 days after emergence) of 11.93 mg N plant-1 day-1 occurred with the symbiotic combination of Carioca × C-05, while the poorest rate of 0.55 mg N plant-1 day-1 was recorded with Venezuela-350 × C-89. The best symbiotic combinations always showed the highest relative nitrogenase efficiency, but the differences in N2-fixation rates cannot be explained solely in terms of conservation of energy by recycling of H2. This requires further investigation.	
Palavras-Chave: 	Acetylene reducion assay; Feijoeiro; Hydrogenase.	
Thesagro: 	Feijão; Fixação de Nitrogênio; Nitrogenase; Nitrogênio; Nodulação; Phaseolus Vulgaris; Rhizobium.	
Thesaurus Nal: 	acetylene; Ara; beans; nodulation.	
Categoria do assunto: 	F Plantas e Produtos de Origem Vegetal
X Pesquisa, Tecnologia e Engenharia	
Registro original: 	Embrapa Soja (CNPSO)	
Exemplares: 	CNPAF - (8052-1) - UPC - AP - PP - 1989 -  - 1989 - DIS
CNPSO - (13816-1) - UPC - AP - DD -  -  -  - DIS