Agressividade, caracterização molecular de isolados de Pantoea ananatis e nanoparticulas no controle da bactéria na cultura do milho

Abstract

The maize white spot, caused by Pantoea ananatis stands out as one of the main foliar diseases of culture. For the management of this disease it is recommended the use of resistant genotypes and chemicals that there has been presenting efficiency, therefore a technological innovation in chemical control of phytopathogens should be evaluated in the control of the disease.Thus, the present work had as objectives: to assess the aggressiveness of isolates of P. ananatis; molecularly characterize isolates of P. ananatis and to evaluate the effect of nanoparticles in control of bacteria in corn plants For the evaluation of aggressiveness were used nine isolates of P. ananatis inoculated in three maize genotypes (DKB230, AG9025, 2B810PW), with four replications. The severity of white spot of leaves was evaluated at 2, 4, 6 and 8 days after inoculation, using a scale of note; for molecular characterization werw studied 23 isolates of P. ananatis using the specific primers ANAF/ANAR and universal BOX. To control with nanoparticles were used nanocrystals of (ZnO) doped with four elements - copper (Cu), iron (Fe), manganese (Mn), and nickel (Ni) - in different concentrations and in two distinct forms of control. The bacterial isolates UFU18 and UFU B13 were more aggressive in maize genotypes susceptible (DKB230, AGV9025), and in the resistant genotype (2B810PW) there was no disease development of the disease. The isolates were identified as P. ananatis using specific primer and allowed the study of genetic diversity of the isolates with primer BOX. The use of nanocrystals of zinc oxide (ZnO) doped with copper (Cu) and manganese (Mn) reduced disease severity in maze plants in greenhouse.