Data/hora: 02/06/2024 16:47:40

Biblioteca(s): | Embrapa Agrobiologia; Embrapa Meio Ambiente.
Data corrente: | 25/05/1995
Data da última atualização: | 03/03/2011
Autoria: | COUTINHO, H. L. C.
Afiliação: | EMBRAPA-CNPMA.
Título: | Studies of Bradyrhizobia from the Brazilian Cerrados.
Ano de publicação: | 1993
Fonte/Imprenta: | Bristol: University of Bristol, 1993.
Páginas: | 156f.
Idioma: | Inglês
Notas: | Tese Doutorado.
Conteúdo: | The exploitation of soybeans in Brazil was developed concomitantly with selection of bradyrhizobia which were able to survive and nodulate well in the brazilian environment. Strains with high efficiency in nitrogen fixation nodulated poorly in the cerrados. Their derivatives, obtained from nodules grown in cerrado soils, were more successful in nodulating soybeans when inoculated to those soils, and were reported to have become more resistant to some antibiotics. Inefficiente strains which nodulated very well in the cerrados were reported to be highly resistant to streptomycin, which led workers to suggest that antibiotic resistance was important for the survival of bradyrhizobia in cerrado soils. This works describes the molecular characterisation of a numberof strains and their derivatives, varying in their capacity to compete for nodulation in the cerrados. Three methods were used: 1) pyrolysis mass spectometry, a phenotypic analysis; 2) multiple arbitrary amplicon fingerprinting and 3) restricted fragments length polymorphism with repeated sequences, which are techniques for DNA fingerprinting. The first method was also used to analyse exopolysaccharides extracted from strains and isolates of Bradyrhizobium japonicum. The use of these techniques is explained and their usefulness for microbial ecology studies assessed and discussed. The results obtained show that derivatives obtained from the cerrados have changed their exopolysaccharides compared to their parental strains. Antibiotic resistance was also...
Palavras-Chave: | Brasil; Growth media; MAAP; PCR; Proteinase lysis.
Thesagro: | Bradyrhizobium Japonicum; Cerrado; Solo.
Thesaurus Nal: | antibiotic resistance; Bradyrhizobium; Brazil; data analysis; nitrogen fixation; savannas; soil; soybeans; strains.
Categoria do assunto: | --
Registro original: | Embrapa Meio Ambiente (CNPMA)

Exemplares:

CNPMA - (2895-1) - ADD - TS - PP - 0325 -  - 1993.00325 - DIS
CNPAB - (25375-1) - ADD - TS - -- - 631.4 - C871s - 1994.00029 - DIS