Insects called leafminers infest citrus trees, leaving open woulds on the leaves and increasing the plant's susceptibility to citrus canker infections. While this disease is primarily cosmetic, prompt treatment prevents the disease from infecting nearby healthy trees. Septoria. In this work we demonstrate that copper treatment induces the viable but nonculturable (VBNC) state in Xac but does not prevent the development of symptoms in susceptible plants. Copper-based products are routinely used as a standard control measure for citrus canker. However, the copper rate should probably be reduced to 1/2 to 1 lb/acre Copper-based fungicides can be used to manage coastal diseases such as melanose, citrus scab, Alternaria. Using copper sprays to control diseases in citrus . Copper will probably have to be applied during those times now to assure control of citrus canker. Most infections occur between April and July on oranges and three to four applications of copper-containing materials at 3-week intervals should be sufficient to obtain relatively clean fruit. Citrus canker management involves the use of the timely applications of copper-containing products and windbreaks to hinder inoculum dispersal. Copper hydroxide is sprayed every 3 weeks (or more) for citrus canker control, a bacterial disease of citrus, and for control of fungal diseases throughout the growing season. April 2017 Primefact 757 second edition Agriculture NSW . copper, will also control canker. However, in the past, we recom-mend that strobilurins be applied dur-ing hot, dry periods to avoid copper damage to fresh fruit. brown spot and citrus black spot, as well as greasy spot, brown rot and .