Thermostability of antigens associated with serotype of Rhizobium japonicum.

Antigenic analysis of Rhizobium japonicum by immunodiffusion.

Immunodiffusion reactions were studied with seven strains of Rhizobium japonicum and three strains of the cowpea miscellany by using antisera against eight of the strains. Most strains yielded only weak precipitin bands when untreated cell suspensions were used as antigens in the diffusions. Ultrasonic disruption or heat treatment of the cells led to stronger bands, and immersion in boiling wat...

Serological Relatedness of Rhizobium fredii to Other Rhizobia and to the Bradyrhizobia.

Several isolates of Rhizobium fredii were examined for their serological relatedness to each other, to Bradyrhizobium japonicum, and to other fast- and slow-growing rhizobia. Immunofluorescence, agglutination, and immunodiffusion analyses indicated that R. fredii contains at least three separate somatic serogroups, USDA 192, USDA 194, and USDA 205. There was no cross-reaction between any of the...

بررسی آنالیز رشد ارقام سویا تحت تأثیر نژادهای باکتری Rhizobium japonicum

Population Densities of Rhizobium japonicum Strain 123 Estimated Directly in Soil and Rhizospheres.

Rhizobium japonicum serotype 123 was enumerated in soil and rhizospheres by fluorescent antibody techniques. Counting efficiency was estimated to be about 30%. Indigenous populations of strain 123 ranged from a few hundred to a few thousand per gram of field soil before planting. Rhizosphere effects from field-grown soybean plants were modest, reaching a maximum of about 2 x 10 cells of strain ...

Conservation of symbiotic nitrogen fixation gene sequences in Rhizobium japonicum and Bradyrhizobium japonicum.

Southern hybridization with nif (nitrogen fixation) and nod (nodulation) DNA probes from Rhizobium meliloti against intact plasmid DNA of Rhizobium japonicum and Bradyrhizobium japonicum strains indicated that both nif and nod sequences are on plasmid DNA in most R. japonicum strains. An exception is found with R. japonicum strain USDA194 and all B. japonicum strains where nif and nod sequences...