Sunburn protectant decreases the incidence of bull's eye and white rots in 'Fuji Standard' and 'Pink Lady' apples/ Protetor solar diminui a incidencia das podridoes 'olho-de-boi' e 'branca' em macas 'Fuji Standard' e 'Pink Lady'

Bull's eye rot (Cryptosporiosis perennans) and white rot (Botryosphaeria dothidea) are among the major apple summer diseases in Brazil. The aim of this study was to evaluate the effect of a protective film consisting of carnauba wax and clay (Raynox®) at doses of 2.5% and 5.0% in infection of C. perennans and B. dothidea in 'Fuji Standard' and 'Pink Lady' apple cultivars. Apple trees were sprayed five times from December 2007 to March 2008, as predicting of adequate conditions for the occurrence of fruit damage and growth. At harvest, the apples were inoculated with both pathogens and evaluated for incidence of decay. Indifferent to dose, the use of Raynox® reduced the incidence of white rot and bull's eye rot in 67% and 42% in 'Fuji Standard', and 43% and 42% in 'Pink Lady', respectively. Increasing the dose increased the efficiency of the product for the control of bull's eye rot. At dose of 2.5%, control of bull's eye rot was 19% and 20%, respectively, of 'Fuji Standard' and 'Pink Lady' apples, while for the same cultivars, but with dose of 5.0%, these values were 65% and 63%. More studies are needed to adjust the dose and application criteria for the sunburn protectant could be recommended.