Agrobacterium bv. 1 Strains Isolated from Nodules of Tropical Legumes

Bacterial strains were isolated from root nodules of various legumes, mainly trees, from different places in Africa. Polyphasic taxonomy, including numerical analysis of comparative whole-cell protein patterns obtained by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), 16S rRNA gene sequencing, auxanographic tests (API 50), and DNA:DNA hybridizations indicated that these strains belonged to Agrobacterium biovar 1. These strains were not capable of inducing any nodule or tumor formation on plants. No PCR amplification was observed using nif H primers, suggesting that they do not carry symbiotic genes. Biological implications of the presence of Agrobacterium in nodules are discussed.