Peroxidase activity and total phenol content in citrus cuttings treated with different copper sources

► Different copper formulations, cupric oxychloride, cuprous oxide, chelated copper and copper sulphate on the evaluate of lemon rootstock grafted with cv. Valencia', were studied. ► Plant growth measurement, peroxidase activity and phenol content were investigated. ► Copper formulations did not change plant height, diameter, leaf and root dry weight. ► Cuprous oxide promoted the antioxidant system analyzed.