Alternatives to increase the red color of the peel in ‘Daiane’ and ‘Venice’ apples

Abstract This study aimed evaluate the effect of biostimulants, foliar fertilizers and ethephon on the red color in the peel of ‘Daiane’ and ‘Venice’ apples. The experiments were conducted in Caçador/SC, during 2015/2016 and 2016/2017 seasons. In 2015/2016, the treatments were: Control; Biostimulant I; Foliar fertilizer I + Foliar fertilizer II; Biostimulant II and KCl. In 2016/2017, was included the Ethephon treatment. In 2016/2017, Biostimulant I, Foliar fertilizer I + Foliar fertilizer II and Biostimulant II increased the percentage of ‘Daiane’ and ‘Venice’ apples with greater red peel cover, without affecting the quality and maturity of the fruits. In both cultivars, ethephon was treatment that promoted a higher percentage of apples in the category above 80% of red color. Ethephon increased red color intensity of ‘Daiane’ and ‘Venice’ apples, anthocyanin content, starch index, ethylene production and yellowing of background color of the fruits. The red coloration of ‘Venice’ apple peels is enhanced with ethephon, Biostimulant I and Foliar fertilizer I + Foliar fertilizer II and Daiane apples with ethephon, Foliar fertilizer I + Foliar fertilizer II and Biostimulant II.