Cell morphology and cell size analysis of E. meliloti strains. Cell size analysis with Pixcavator IA 220.127.116.11 software  of logarithmically grown cultures (OD600=0.6) in TY medium of AK58, BO21CC, plus other completely sequenced E. meliloti strains is reported. Cell size is expressed as cell area in µm2, while roundness is the ratio between the two main axes of the cell. Standard errors after more than 300 individual observations are reported. Different letters indicate significant differences (P<0.05) after 1-way ANOVA.