Pseudomonas savastanoi pv. causes olive knot disease that afflicts 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 cycloheximide. Symptoms were clear under 20X magnification 10 days. This will facilitate rapid screening germplasm collection for resista...

The objective of this study was to determine the chemical composition and antibacterial activity of essential oils (EOs) of Tagetes minuta against three phytopathogenic bacteria Pseudomonas savastanoi pv. phaseolicola, Xanthomonas axonopodis pv. phaseoli, and Xanthomonas axonopodis pv. manihotis. The essential oils were extracted using steam distillation method in a modified Clevenger-type appa...

Olive (Olea europaea) is a crop of great agronomic, economic and cultural interest for the Mediterranean Basin, although increase in world demand olive oil expanding its cultivation by other countries southern hemisphere. The main pathogens include bacteria (Pseudomonas savastanoi pv. savastanoi, Xylella fastidiosa), fungi (Colletotrichum spp., Verticillium dahliae, Fusarium spp. Rhizoctonia so...

The study of the molecular basis of tree diseases is lately receiving a renewed attention, especially with the emerging perception that pathogens require specific pathogenicity and virulence factors to successfully colonize woody hosts. Pathosystems involving woody plants are notoriously difficult to study, although the use of model bacterial strains together with genetically homogeneous microp...

Seasonal dynamics of Pseudomonas savastanoi pv. savastanoi (Psv) on stems and leaves from symptomless shoots of naturally infected olive trees was monitored in Spanish olive orchards. Data inferred from the comparison between washing of leaves and dilution-plating versus leaf printing of individual leaves suggested that Psv population sizes varied by over several orders of magnitude, among leav...

Three endophytic bacterial isolates were obtained in Italy from olive knots caused by Pseudomonas savastanoi pv. savastanoi. Phenotypic tests in combination with 16S rRNA gene sequence analysis indicated a phylogenetic position for these isolates in the genera Erwinia or Pantoea, and revealed two other strains with highly similar 16S rRNA gene sequences (>99 %), CECT 5262 and CECT 5264, obtaine...