CHARACTERISATION OF SOYBEAN RHIZOBIAL STRAINS FROM JAVA AND SUMATRA

To get insight in the structure of soybean rhizobial population native to Indonesian soils, a thorough survey of the occurrence of the soybean rhizobia were conducted in several locations in Java and Sumatra. A total of 51 different isolates of rhizobial strains were characterised phenotypically based on their symbiotic properties, and genetically using amplified ribosomal DNA restriction analysis (ARDRA). Based on their nodulation capacity on both soybean and the native legume mungbean, these rhizobial strains could be divided into a group of 16 strains specific for soybean only and another group of 35 promiscuous strains that nodulated both leguminous plants. Based on ARDRA of PCRamplified 16S rDNA and 16S-23S rDNA spacer fragments, the rhizobial strains isolated from Java differed with those from Sumatra. Six Java isolates and only one Sumatra isolate were classified as Bradyrhizobium japonicum and these similar to that of B. japonicum strain USDA 110. All these B. japonicum strains were highly specific for soybean. One isolate from Java showed a rather unique position. The remaining strains from Java (20), which were symbiotically promiscuous strains, were clustered in another group. This group and another group containing most Sumatra isolates were distinct from B. japonicum USDA 110 and therefore it is tempting to speculate that these represent indigenous soybean rhizobial bacteria. Application of agricultural practices, such as enhancement of rhizobial population, to increase soybean production is still essential and noteworthy in Sumatra.

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Characterization of variants of Bradyrhizobium elkanii and B. japonicum and symbiotic behaviour in soybeans

Ciência Rural ◽

10.1590/s0103-84782004000500020 ◽

2004 ◽

Vol 34 (5) ◽

pp. 1459-1464 ◽

Cited By ~ 3

Author(s):

Marcia de Vargas Kober ◽

Enilson Luiz Saccol de Sá ◽

João Ruy Jardim Freire ◽

Adriana Giongo

Keyword(s):

Antibiotic Resistance ◽

Bradyrhizobium Japonicum ◽

Competitive Ability ◽

Colony Morphology ◽

Nodule Formation ◽

Phenotypic Characteristics ◽

Plant Variety ◽

Nodulation Capacity ◽

Japonicum Strain

Variation in rhizobia strains isn’t a desirable fact based mainly on the possibility of unexpected results on legume inoculation. In this work, we studied the variability on phenotypic characteristics and genetic stability of rhizobia strains recommended for soybean inoculation. Variants with stable colony morphology were obtained from Bradyrhizobium japonicum strain SEMIA 5080 and from B. elkanii SEMIA 5019. Variants from SEMIA 587 obtained by another author were also used. The variants differed on colony characteristics, nodulation capacity, nitrogen fixation efficiency and competitive ability for nodule formation in two soybean varieties (Jacui 7 and IAS 5). Symbiotic behavior varied according to plant variety. Only the variants 5019 G and 5019 P differed on the isoenzymatic profile. There were differences in antibiotic resistance between variants from two strains. Correlation between symbiotic characteristics and colony morphology or antibiotic resistance wasn’t conclusive. The results indicate that the variability in rhizobia strains might be an important factor to be considered in strain selection and preservation of cultures for inoculant production.

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Latitudinal Characteristic Nodule Composition of Soybean-Nodulating Bradyrhizobia: Temperature-Dependent Proliferation in Soil or Infection?

Horticulturae ◽

10.3390/horticulturae7020022 ◽

2021 ◽

Vol 7 (2) ◽

pp. 22

Author(s):

Md Hafizur Rahman Hafiz ◽

Ahsanul Salehin ◽

Fumihiko Adachi ◽

Masayuki Omichi ◽

Yuichi Saeki ◽

...

Keyword(s):

Bradyrhizobium Japonicum ◽

23S Rrna ◽

Temperature Dependent ◽

Local Climate ◽

Climate Conditions ◽

Its Gene ◽

Soybean Rhizobia ◽

Species Specific ◽

Continental Climate ◽

Japonicum Strain

A species-specific latitudinal distribution of soybean rhizobia has been reported; Bradyrhizobium japonicum and B. elkanii dominate in nodules in northern and southern areas, respectively. The aim of this study was to elucidate whether temperature-dependent proliferation in soil or infection is more reliable for determining the latitudinal characteristic distribution of soybean-nodulating rhizobia under local climate conditions. Three study locations, Fukagawa (temperate continental climate), Matsue and Miyazaki (humid sub-tropical climate), were selected in Japan. Each soil sample was transported to the other study locations, and soybean cv. Orihime (non-Rj) was pot-cultivated using three soils at three study locations for two successive years. Species composition of Bradyrhizobium in the nodules was analyzed based on the partial 16S rRNA and 16S–23S rRNA ITS gene sequences. Two Bradyrhizobium japonicum (Bj11 and BjS10J) clusters and one B. elkanii (BeL7) cluster were phylogenetically sub-grouped into two (Bj11-1-2) and four clusters (BjS10J-1-4) based on the ITS sequence. In the Fukagawa soil, Bj11-1 dominated (80–87%) in all study locations. In the Matsue soil, the composition was similar in the Matsue and Miyazaki locations, in which BeL7 dominated (70–73%), while in the Fukagawa location, BeL7 decreased to 53% and Bj11-1 and BjS10J-3 increased. In the Miyazaki soil, BeL7 dominated at 77%, and BeL7 decreased to 13% and 33% in the Fukagawa and Matsue locations, respectively, while BjS10J-2 and BjS10J-4 increased. It was supposed that the B. japonicum strain preferably proliferated in the Fukagawa location, leading to its nodule dominancy, while in the Miyazaki location, temperature-dependent infection would lead to the nodule dominancy of B. elkanii, and both factors would be involved in the Matsue location.

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Identification of Major Streptococcal Species by rrn-Amplified Ribosomal DNA Restriction Analysis

Journal of Clinical Microbiology ◽

10.1128/jcm.41.2.657-666.2003 ◽

2003 ◽

Vol 41 (2) ◽

pp. 657-666 ◽

Cited By ~ 15

Author(s):

L. Schlegel ◽

F. Grimont ◽

P. A. D. Grimont ◽

A. Bouvet

Keyword(s):

Ribosomal Dna ◽

Restriction Analysis ◽

Streptococcal Species ◽

Dna Restriction

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Extracellular hydrolytic enzyme production by proteolytic bacteria from the Antarctic

Polish Polar Research ◽

10.2478/popore-2013-0014 ◽

2013 ◽

Vol 34 (3) ◽

pp. 253-267 ◽

Cited By ~ 10

Author(s):

Mauro Tropeano ◽

Susana Vázquez ◽

Silvia Coria ◽

Adrián Turjanski ◽

Daniel Cicero ◽

...

Keyword(s):

Extracellular Enzymes ◽

Restriction Analysis ◽

Hydrolytic Enzyme ◽

Hydrolytic Enzymes ◽

Extracellular Enzyme ◽

16S Rrna Genes ◽

Rrna Genes ◽

Potter Cove ◽

Starting Point ◽

Dna Restriction

AbstractCold−adapted marine bacteria producing extracellular hydrolytic enzymes are important for their industrial application and play a key role in degradation of particulate organic matter in their natural environment. In this work, members of a previously−obtained protease−producing bacterial collection isolated from different marine sources from Potter Cove (King George Island, South Shetlands) were taxonomically identified and screened for their ability to produce other economically relevant enzymes. Eighty−eight proteolytic bacterial isolates were grouped into 25 phylotypes based on their Amplified Ribosomal DNA Restriction Analysis profiles. The sequencing of the 16S rRNA genes from representative isolates of the phylotypes showed that the predominant culturable protease−producing bacteria belonged to the class Gammaproteobacteria and were affiliated to the genera Pseudomonas, Shewanella, Colwellia, and Pseudoalteromonas, the latter being the predominant group (64% of isolates). In addition, members of the classes Actinobacteria, Bacilli and Flavobacteria were found. Among the 88 isolates screened we detected producers of amylases (21), pectinases (67), cellulases (53), CM−cellulases (68), xylanases (55) and agarases (57). More than 85% of the isolates showed at least one of the extracellular enzymatic activities tested, with some of them producing up to six extracellular enzymes. Our results confirmed that using selective conditions to isolate producers of one extracellular enzyme activity increases the probability of recovering bacteria that will also produce additional extracellular enzymes. This finding establishes a starting point for future programs oriented to the prospecting for biomolecules in Antarctica.

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