Detection of culturable, viable but non-culturable (VBNC) and dead cells of <i>Clavibacter michiganensis</i> subsp. <i>michiganensis</i> (<i>Cmm</i>) by PMAxx-qPCR from artificially inoculated tomato seed.

<p>Ten tomato seeds were soaked in log phase (A), copper-induced VBNC (B) and heat-killed (C) <i>Cmm</i> cells suspension (10⁸ CFU mL^-1) by vacuum infiltration. After inoculation, the seed was broken by a ball mill and diluted 20-fold with 0.85% NaCl solution, followed by treatment with or without PMAxx at a final concentration of 20 μM. DNA was extracted after PMAxx treatment and used for qPCR assay. Cycle threshold (Ct) of qPCR was separated using multiple range test, and means labeled with different letters were significantly different (<i>P</i> < 0.05).