The effect of weekly sprayings with streptomycin sulfate + oxytetracycline (0.8 g ia L-1), copper oxychloride (2.4 g ia L-1) and Agrobio fertilizer (5%) plus a control (water) was evaluated in the control of bacterial spot, the microbial flora in the phyloplan, and over yield in three bell pepper cultivars (Magda, Cascadura Itaipu and Magali R). The study was carried out under field conditions from May to December 2002. A randomized complete block experimental design was used with four replications in a 4 x 3 factorial design. Weekly assessments were made for plant height (cm); number of stems; total number of leaves; number of fallen leaves; number of leaves with visible symptoms; damaged leaf area (severity), and yield (t ha-1). The microbial population resident in the phyloplan and fruits was quantified at the same time. There was no effect of treatments on yield, but an effect was observed on plant growth, on leaf spot and on the microbial flora. Copper oxychloride inhibited plant development, reduced number of fallen leaves and decreased the bacterial flora. Agrobio stimulated plant growth and, like streptomycin sulfate + oxytetracycline, inhibited the bacterial population, except Bacillus sp., and fungi, except Cladosporium sp. in the phyloplan. Among the genotypes, the hybrid Magali R was significantly superior in plant vigor, yield and resistance to bacterial spot. The results suggest bactericidal activity of the Agrobio under field conditions.
Capsicum annuum; Xanthomonas euvesicatoria; control; yield
