control of xanthomonas campestris pv. phaseoli on bean_using copper compounds and plant activator

The efficacy of several new formulations of copper compounds, namely Cuprozin 35 WP (copper-oxychloride), Cuproxat (copper-sulphate), Funguran OH (copper-hydroxide)and the plant activator Bion(acibenzolar-S-methyl), and their combinations with dithiocarbamates(Dithane M-70) was estimated in controlling Xanthomonas campestris pv. phaseoli (artificial inoculation) in field conditions in two localities during 2006. In the locality Zemun, the efficacy of copper compounds ranged from 92.7% to 98.5%. The plant activator Bion 50 WG exhibited similar efficacy (94.4-97.1%). Combinations of Funguran OH and Dithane M-70, applied at different concentrations, also showed high efficacy (98.3-99.3%), as well as the combinations of Bion 50 WG and the other bactericides (95.5-96.8%). There was no significantdifference between the efficacies achieved by the compounds applied individually and their combinations, except Cuproxat, which exhibited decreased efficacy at lower concentration. In the locality Smederevska Palanka, the efficacy of copper compounds was 95.0-98.2%, while Bion achieved 96.8-97.7% efficacy. Combinations of copper-hydroxide(Funguran OH) and dithiocarbamates (Dithane M-70) also showed high efficacy (98.1-99.4%) but without a significant difference. The efficacy of combinations of Bion and copper-hydroxide, and Bion and mancozeb was 97.9-98.9%. There was no significant difference in the efficacies of the bactericides tested or the efficacies of their combinations in that locality.Our investigation confirmed high efficacy of acibenzolar-S-methyl, which was equal to the efficacy of standard bactericide treatment. This compound therefore offers a very good alternative to conventional chemicals used for controlling bacterial diseases in beans.