Serogroups of Rhizobium japonicum in Soybean Nodules Sampled in Iowa¹

Abstract

Serogroups of Rhizobium japonicum present in the nodules of soybeans and their relationship to soil properties were studied on 613 nodule samples obtained at 75 locations during 1965 and 1966. The homogenized nodule suspensions were typed serologically by a quick agglutination test using somatic antisera of cultures of R. japonicure representing seven serogroups. Only 2.8% and 1.1% of the nodules tested failed to react with one of the seven antisera in 1965 and 1966, respectively. R. japonicum serogroup 123 was the dominant serogroup found in soybean nodules on soils below pH 7.5, while serogroup 135 dominated when the soil pH was greater than 7.8. Individual serogroups were related to at least 2 and as many as 6 soil properties. In 1966, 81% of the variation in the occurrence of serogroup 135 was attributed to soil pH. Relating the occurrence of serogroup 135 to all soil properties accounted for 84% of the variation or only 3% more than pH alone. Less of the variation in other serogroups was attributed to soil properties.

Plasmids, Biological Properties and Efficacy of Nitrogen Fixation in Rhizobium japonicum Strains Indigenous to Alkaline Soils

“…Soil pH, soil temperature, planting date and variations in resistance to antagonistic soil microflora have been related to the persistence of particular strains of R . japonicum in soil (Caldwell & Weber, 1970;Drapeau et al, 1973;Ham et al, 1971 ;Smith & Miller, 1974;Weber & Miller, 1972). For example, Ham et al (1971) substantiated and extended the work of Damirgi et al (1967), showing that Iowa (U.S.A.) serogroup 135 R. japonicum strains were significantly associated (P > 0.001) with nodules produced by soybeans grown on alkaline soils (pH 2 7-5) while serogroup 123 predominated in Iowa soils below this pH.…”

“…Only two procedures have been commonly used to distinguish and identify strains of R. japonicum -serotyping (Ham et al, 1971 ;Johnson & Means, 1963) and bacteriophage typing (Kowalski et al, 1974). Thus, a more definitive means of strain differentiation is desirable.…”

Serological properties and intrinsic antibiotic resistance of soybean bradyrhizobia isolated from Thailand

“…Among the 94 Thai strains tested, 57 strains (60.6% of the total) had antigens for USDA 124 antiserum and 64% of the strains with antigens of USDA 124 also reacted with both antisera of USDA 4 and 110. Most of the Thai strains did not harbor the antigens of USDA strains 6,46,76,94,122,123, and 125 which were all reported to be the predominant serological groups in Japan, Korea, and United States (Caldwell and Vest 1968;Ham et al 1971;Noel and Brill 1980;Keyser et al 1984;Kamicker and Brill 1986;Sawada et al 1989;Kang et al 1991). These findings indicate that there are predominant serological types specific to temperate and tropical climatic zones.…”

“…Serogroup 123 strains were predominant in the midwestern United States (Caldwell and Vest 1968;Ham et al 1971;Noel and Brill 1980;Keyser et al 1984;Kamicker and Brill 1986) and the strains which produced rhizobitoxine belonged to serogroups 31, 76, 94, and 130 (La Favre and Eaglesham 1986;Devine et al 1988;Fuhrmann 1990;Minamisawa 1990). Serological and genetic characters of several serogroups isolated in the United States have been intensively studied (Schmidt et al 1986;· Sadowsky et al 1987a· Sadowsky et al , b, 1990.…”

Characterization of Soybean-Nodulating Rhizobial Communities and Diversity

“…Keyser et al (1984) examined the distribution of indigenous soybean-nodulating rhizobia in the United States and found that serogroup 123 was dominant in northern regions and B. elkanii in southern regions. Other studies support these results, with some exceptions in the case of alkaline soils, in which Bradyrhizobium serogroup 135 or Sinorhizobium/ Ensifer fredii predominate (Damirgi et al, 1967;Ham et al, 1971;Kowalski et al, 1974;Gross et al, 1979;Suzuki et al, 2008). Further studies are still needed, however, to examine the many environmental factors potentially affecting indigenous bradyrhizobia.…”