Antibacterial activity of some commercial bacteriotoxicants against tomato bacterial spot disease caused by the bacterium, Xanthomonas vesicatoria was screened in vitro and in vivo. Antagonistic effect of tested bacteriotoxicants i.e. Bio arc “Bacillus megaterium 2.5x107 CFU/g” (at conc. 1.5, 2.5 and 3.5 g/L), garlic oil (at conc. 0.3, 0.5 and 1.0%), oxytetracycline (at conc. 12.0, 12.5 and 13.0 μg/ml) and copper oxychloride (at conc. 1.0, 1.5, 2.0 g/L) was achieved. All tested treatments had clear significant inhibitory effects in vitro on growth of X. vesicatoria with increasing concentration of each bacteriotoxicant in comparing with control treatment. Maximum inhibitory effect was attained by copper oxychloride at 2.0 g/L (6.87 mm) followed by oxytetracycline at 13.0 μg/ml (4.70 mm), garlic oil at 1.0% (3.90 mm) and Bio arc at 3.5 g/L (2.83 mm). Applying of median concentration of each tested commercial bacteriotoxicant under open field condition individually in regular or in un-regular succession (in program form) as foliar spray considerably and significantly reduced bacterial spot disease development (disease % and disease severity %). Maximum reduction in disease development was achieved by applying prog-4 which served as treated control (sprayed with copper oxychloride) followed by prog-8 and prog-10, respectively. All tested treatments (programs) were significantly increased total tomato yield. Moreover, all tested programs increased clearly total phenol content, peroxidase, polyphenoloxidase and chitinase activity as well as, increased vitamin C content. |
