Bacterial contamination in sweetpotato germplasm is about ~ 0.43% (21 accessions) of the collection. The bacterial contamination in sweetpotato appears to be endogenous and involves a suite of bacteria. Infection seems to be connected to the origin of the host plant as virtually all sweetpotato derived from African countries contain some type of bacterial infection. Although it is intriguing to speculate a beneficial effect of such endogenous bacteria in sweetpotato, no evidence of any beneficial effect has been reported. In potato, the incidence of bacterial contamination is less than 0.1% (2 accessions) and therefore is a minor issue.

Bacteria elimination procedures consist of exposing the contaminated accession to a broad-spectrum antibiotic for a controlled time (Figure 1). If the bacteria are not eliminated, the accession is acclimatized in a greenhouse and reintroduced to in vitro conditions with previous disinfection steps.