Genetic Characterization of Soybean Rhizobia in Paraguay

摘要: The soybean is an exotic plant introduced in Paraguay this century; commercial cropping expanded after the 1970s. Inoculation practiced just 15 to 20% of areas, but root nodulation occurs most sites where soybeans grow. Little known about rhizobial diversity South America, and no study has been performed until time. Therefore, study, molecular characterization 78 isolates from nodules, collected under field conditions 16 located two main producing states, Alto Parana Itapua, was undertaken. A high level genetic detected by ERIC-REP-PCR analysis, with majority representing unique strains. Most 58 characterized slow growth alkaline reactions a medium containing mannitol as carbon source were clustered strains representative Bradyrhizobium japonicum elkanii species, 16S ribosomal DNA (rDNA) sequences 5 those confirmed species identities. However, growers highly polymorphic relation reference strains, including five carried inoculants neighboring countries, thus indicating that Paraguayan might represent native bradyrhizobia. Twenty profiles fast acid vitro, them showed rDNA identities Rhizobium genomic Q. other identity Agrobacterium spp., both these established efficient symbioses plants.