An in vitro bioassay for evaluating the virulence of Pseudomonas savastanoi pv savastanoi isolates on olive

Pseudomonas savastanoi pv. savastanoi causes olive knot disease that afflicts olive trees globally. A sensitive and reproducible in vitro pathogenicity bioassay using detached leaf segments was developed after isolation of Psav on KB medium amended with vancomycin, cephalexin and cycloheximide. Symptoms were clear under 20X magnification after 10 days. This bioassay will facilitate rapid screening of olive germplasm collection for resistance to Psav.