This study was conducted to evaluate Egyptian
propolis to control tomato bacterial wilt caused by Ralstonia
solanacearum under in vitro and in vivo conditions.
In vitro, three concentrations of water extract of propolis
[1 mg/mL (PC1); 10 mg/mL (PC2); and 100 mg/mL
(PC3)] showed antagonistic activity against R. solanacearum.
All concentrations significantly reduced the
growth of the pathogen compared to control treatment, PC3
caused the highest growth reduction while PC1 caused the
lowest reduction compared to water treatment. When the
above three concentrations were applied to tomato seeds
under laboratory conditions, they improved seed germination
relative to control seeds treated with sterile distilled
water. In both greenhouse and field experiments, PC3 gave
a higher reduction in disease severity than PC1 and PC2;
also this concentration caused the highest biomass percentage
under greenhouse conditions. As recorded in field
experiments, PC3 treatment resulted in a control efficacy of
76.9 and 71.7%, respectively, in two trial seasons. The
highest increase percentage of yield per plant was recorded
for PC3.