Spray Volume and Rate Based on the Tree Row Volume for a Sustainable Use of Copper in the Control of Citrus Canker

Copper is the most efficient pesticide for control of citrus canker (Xanthomonas citri subsp. citri). To mitigate environmental impacts and costs, copper sprays in orchards are being optimized based on tree row volume (TRV). A previous investigation allowed significant reductions spray rates. Nevertheless, results also indicated need additional studies. The aim this work was to assess whether both metallic rate TRV may be further reduced. field trial carried out during two seasons a 3-year-old commercial orchard Pera sweet orange located municipality Paranavaí, Paraná, Brazil. volumes 20 40 ml mixture per m 3 canopy were assessed combination with rates 10.5, 21.0, 36.8, or 52.5 mg/m . Disease measured as temporal progress incidence leaves, cumulative dropped fruit canker, diseased at harvest. quality by measuring deposition leaf coverage. treatment highest lowest use water 36.8 Regression analyses that minimum threshold ∼1.5 µg Cu 2+ /cm 2 area. In addition, necessary achieve 35 ml/m 30 did not efficiently disease due deficient coverage treated surfaces. This study demonstrated it possible even lower amounts without interfering efficiency canker.