Acibenzolar-S-methyl (ASM) is a plant activator that triggers systemic acquired resistance that is labeled for use in Brazil for managing tomato bacterial spot. The aim of this study was to define the optimum relationship between interval and number of applications of ASM for the most efficacious control of bacterial spot on processing tomato. Four intervals between applications (4, 7, 10, and 14 days) and four application frequencies (4, 6, 8, and 10 applications) were evaluated in five trials performed between 2010 and 2011 in Brasília, Distrito Federal, and in Morrinhos, in the state of Goiás. Copper hydroxide (CH) was applied after ASM applications to complete 13 applications per growing season. Two check treatments were added: standard CH weekly applications and untreated. The following variables were evaluated: severity of bacterial spot, yield, percentage of ripe and rotten fruit, soluble solids content, and the benefit/cost ratio. Disease severity varied between treatments in three trials and yield varied in two trials. A greater number of applications resulted in a reduction of bacterial spot, and the ideal interval between applications was between 8 to 10 days. However, there was a reduction in yield with 10 ASM applications. The temporal effect of ASM applications on bacterial spot severity was evaluated under greenhouse conditions. Reduction in disease severity was observed up to 6 days following ASM application. Additionally, the weekly treatment of seven applications of ASM followed by six applications of CH was compared with a standard program of CH under commercial production conditions in Itaberaí, Goiás, where bacterial spot occurred naturally. The program with ASM and CH resulted in significantly less foliar disease severity than the standard program, which did not result in yield gains. In addition, no differences were detected between the two programs for soluble solids content, industrial yield, plant height, and percentage of ripe and rotten fruit.

Biological insecticides can be another pest control method used in integrated pest management; hence there is a demand for scientific information about these products to understand the appropriate application technique. The aim of this study was to evaluate the spray spectra data by different nozzle types using biological insecticide isolated and with adjuvants, as well the surface tension of these spray solutions. For droplet spectra data, a particle size analyzer was used and for surface tension of the spray solution, the method of pendant drop was used. Among the nozzles tested, ADI 11002 provided greater droplets median diameter volume, a lower percentage of droplets with diameters less than 100 μm and also the highest coefficient of uniformity. In general, the addition of adjuvants reduced the median droplet diameter and increased the proportion of drops susceptible to spray drift. By adding adjuvants to the spray solution there was a lower surface tension, which were dependent of the adjuvant chemical group. The Silwet L-77^® adjuvant showed the lowest surface tension among the spray solutions evaluated.