Induction of the viable but non-culturable condition in Xanthomonas campestris pv. campestris in liquid microcosms and sterile soil

Xanthomonas campestris pathovar campestris was examined for the ability to enter the viable but non-culturable (VBNC) state. When nutrients were remov ed from a bacterial culture, the culturability dropped to undetectable leve ls within 6 weeks while the concentration of viable cells remained above 10 (5) cells ml(-1). Addition of cupric sulfate facilitated this process. When bacteria were placed in autoclaved soil, culturability dropped by at least four logs within 5 days of the experiment while the concentration of viabl e cells remained at least two logs higher. These results indicate that the plant pathogen X. campestris can enter the VBNC condition in sterile soil a nd in liquid cultures and that cupric sulfate decreases the time for entry into the VBNC condition. (C) 1999 Federation of European Microbiological So cieties. Published by Elsevier Science B.V. All rights reserved.