Detectability of Pseudomonassyringae pv. aesculi from European Horse Chestnut Using Quantitative PCR Compared with Traditional Isolation

Bleeding cankers on horse chestnut trees (Aesculushippocastanum and Aesculus × carnea), caused by Pseudomonassyringae pv. aesculi, have been reported across Europe. In the present study, we show successful detection of P. syringae aesculi symptomatic in Switzerland using quantitative PCR (qPCR). However, was also detected qPCR from which no isolate obtained through cultivation. Reduced isolation success low copy numbers target gene were correlated with increasing age trees. The potential detecting non-viable evaluated an inoculation experiment dead bacteria detectability DNA cells dropped 34.5% one day after then decreased only slightly until end (22 days inoculation). contrast, bacterial growth observed at any time point inactivation bacteria. To protect trees, evaluating viability actual infection stage bacterium may play important role.