Agrobacterium cavarae sp. nov., isolated from maize (Zea mays L.) roots

A bacterial strain designated as RZME10^T was isolated from a Zea mays L. root collected in Spain. Results of analysis of the 16S rRNA gene sequence showed that this strain belongs to the genus Agrobacterium with Agrobacterium larrymoorei ATCC 51759^T being the most closely related species with 99.9 % sequence similarity. The similarity values of the rpoB, recA, gyrB, atpD and glnII genes between strain RZME10^T and A. larrymoorei ATCC 51759^T were 93.5, 90.0, 88.7, 87.9 and 90.1 %, respectively. The estimated average nucleotide identity using blast and digital DNA-DNA hybridization values between these two strains were 80.4 and 30.2 %, respectively. The major fatty acids of strain RZME10^T are those from summed feature 8 (C_18 : 1 ω6c/C_18 : 1 ω7c) and C_16 : 0. Pathogenicity tests on tomato and carrot roots showed that strain RZME10^T was not able to induce plant tumours. Based on the results of genomic, chemotaxonomic and phenotypic analyses, we propose that strain RZME10^T represents a novel species named Agrobacterium cavarae sp. nov. (type strain RZME10^T=CECT 9795^T=LMG 31257^T).