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The management of citrus canker, caused by Xanthomonas citri subsp. citri, has been widely studied in endemic areas due to the importance of the disease in several citrus producing countries. A set of control measures is well-established, but no study has investigated the efficiency of each measure individually and their combination for disease suppression. This study comprised a 3-year field study to assess the relative contribution of three measures for the control of citrus canker and reduction of crop losses. Windbreak (Wb), copper sprays (Cu), and leafminer control (Lc) were assessed in eight different combinations in a split-split plot design. The orchard was composed of ‘Valencia’ sweet orange trees grafted onto ‘Rangpur’ lime. Casuarina cunninghamiana trees were used as Wb. Cu and Lc sprays were performed every 21 days throughout the year. Individually, Cu showed the highest contribution for canker control, followed by Wb. Lc had no effect on reducing citrus canker. Wb+Cu showed the highest efficiency for control of the disease. This combination reduced the incidence of diseased trees by ~60%, and the incidence of diseased leaves and fruit by ≥ 90% and increased the yield in 2.0 to 2.6-fold in comparison with the unmanaged plots. Cu sprays were important for reducing disease incidence and crop losses, whereas Wb had an additional contribution in minimizing the incidence of cankered, non-marketable fruit. The results indicated that the adoption of these measures of control may depend on the characteristics of the orchard and destination of the production.

Copper is the most efficient pesticide for the control of citrus canker (Xanthomonas citri subsp. citri). To mitigate the environmental impacts and costs, the copper sprays in citrus orchards are being optimized based on the tree-row-volume (TRV). A previous investigation allowed for significant reductions of the spray volume and copper rates. Nevertheless, the results also indicated the need for additional studies. The aim of this work was to assess whether both the spray volume and the metallic copper rate based on the TRV may be further reduced. A field trial was carried out during two seasons in a three-year-old commercial orchard of Pera sweet orange located in the municipality of Paranavaí, Paraná, Brazil. The volumes of 20 and 40 mL of spray mixture/m3 of the tree canopy were assessed in combination with the metallic copper rates of 10.5, 21.0, 36.8 or 52.5 mg/m3. Disease was measured as the temporal progress of canker incidence on leaves, cumulative dropped fruit with canker, and incidence of diseased fruit at harvest. The quality of sprays was assessed by measuring the copper deposition and leaf coverage. The treatment with the highest citrus canker control for the lowest use of water and copper was the combination of 40 mL and 36.8 mg/m3. Regression analyses indicated that the minimum threshold deposition of copper was ~1.5 µg Cu2+/cm2 leaf area. In addition, the lowest spray volume and copper rate necessary to achieve this deposition are 35 mL/m3 and 30 mg/m3. The use of 20 mL/m3 did not efficiently control the disease due to the deficient coverage of treated surfaces. This study demonstrated that is possible to use even lower amounts of copper and water without interfering with efficiency of control of citrus canker.

-The experiment evaluated the agronomic characteristics of 'Prata-anã' and 'Maçã' banana plants, in the São Manuel region of São Paulo state. In the first crop cycle, the number of days from planting to inflorescence and from inflorescence to harvest; the number of shoots until the appearance of inflorescence and during the harvest period; active leaves number at inflorescence appearance and during the harvest period. Were evaluated yield parameters: like average weight of bunch, hand, rachis and fruit; average fruit number per hand and bunch; average fruit diameter and length. Incidences of plague diseases, as well as their severity were also evaluated. Delineation was totally at random, with 2 treatments, 15 replications and 5 useful plants per experimental plot. Both cultivars were characterized by values of descriptive average statistics and standard deviation, for characteristic interests. Number of days from planting to harvest was similar for both ´Prata-anã´ and ´Maçã´, 574 and 567 days respectively. Banana plants showed good phytosanitary quality throughout the whole cycle. Index terms: Banana, Musa spp, micropropagation, cycle. DESEMPENHO AGRONÔMICO DE BANANEIRAS '´PRATA-ANÃ E 'MAÇÃ' MICROPROPAGADASRESUMO -O experimento foi instalado com o objetivo de estudar o desempenho agronômico de cultivares de bananeira Prata-anã e Maçã, na região de São Manuel-SP. Foram avaliadas as seguintes características de desenvolvimento, no primeiro ciclo de produção: número de dias do plantio à floração e da mesma à colheita, número de rebentos (filhos) emitidos até o surgimento da inflorescência e na época da colheita, número de folhas ativas na época do aparecimento da inflorescência e da colheita, e características de rendimento, como peso médio do cacho, ráquis, penca e fruto, número médio de frutos por penca e cacho, comprimento e diâmetro médio dos frutos. Também foi avaliada a incidência de pragas e doenças. Foi empregado o delineamento inteiramente casualizado, com 2 tratamentos, 15 repetições e 5 plantas úteis por parcela experimental. As duas cultivares foram caracterizadas pelos valores das estatísticas descritivas, média e desvio-padrão, para as características de interesse no experimento. Foram estabelecidas possíveis correlações entre medidas de desenvolvimento e produção. As duas cultivares apresentaram ciclo do plantio até a colheita de 574 dias para 'Prata-anã' e 567 dias para 'Maçã', sendo que o ciclo produtivo foi maior na 'Prata-anã'. Não houve problemas de pragas e doenças em todo o ciclo de produção, nas duas cultivares avaliadas. Palavras-chave: Banana, Musa spp, micropropagação, ciclo cultural.