Antagonistic endophytic bacteria associated with nodules of soybean (Glycine max L. ) and plant growth-promoting properties
Braz. j. microbiol
; 49(2): 269-278, Apr.-June 2018. tab, graf
Article
em En
| LILACS
| ID: biblio-889232
Biblioteca responsável:
BR1.1
ABSTRACT
Abstract A total of 276 endophytic bacteria were isolated from the root nodules of soybean (Glycine max L.) grown in 14 sites in Henan Province, China. The inhibitory activity of these bacteria against pathogenic fungus Phytophthora sojae 01 was screened in vitro. Six strains with more than 63% inhibitory activities were further characterized through optical epifluorescence microscopic observation, sequencing, and phylogenetic analysis of 16S rRNA gene, potential plant growth-promoting properties analysis, and plant inoculation assay. On the basis of the phylogeny of 16S rRNA genes, the six endophytic antagonists were identified as belonging to five genera Enterobacter, Acinetobacter, Pseudomonas, Ochrobactrum, and Bacillus. The strain Acinetobacter calcoaceticus DD161 had the strongest inhibitory activity (71.14%) against the P. sojae 01, which caused morphological abnormal changes of fungal mycelia; such changes include fracture, lysis, formation of a protoplast ball at the end of hyphae, and split ends. Except for Ochrobactrum haematophilum DD234, other antagonistic strains showed the capacity to produce siderophore, indole acetic acid, and nitrogen fixation activity. Regression analysis suggested a significant positive correlation between siderophore production and inhibition ratio against P. sojae 01. This study demonstrated that nodule endophytic bacteria are important resources for searching for inhibitors specific to the fungi and for promoting effects for soybean seedlings.
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Texto completo:
1
Índice:
LILACS
Assunto principal:
Reguladores de Crescimento de Plantas
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Glycine max
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Bactérias
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Nódulos Radiculares de Plantas
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Endófitos
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Antibiose
Tipo de estudo:
Risk_factors_studies
País/Região como assunto:
Asia
Idioma:
En
Revista:
Braz. j. microbiol
Assunto da revista:
MICROBIOLOGIA
Ano de publicação:
2018
Tipo de documento:
Article
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Project document