Effects of copper-based foliar fertilizer and controlled release fertilizer on growth and leaf protective enzyme activities of pepper

A pot experiment was conducted on pepper to evaluate the effects of copper based foliar fertilizers（CBFF） and controlled-release fertilizers(CRF) on the concentration of these nutrients, yield, quality, copper partitioning and activities of protective enzymes in plant. The results indicated that different interactions of CBFF and CRF had significant effects on yield. The optimal combination of fertilization for yield was CBFF+CRF+W. Under the optimal application condition, yields were significantly increased by 24.1% and 29.0%, respectively in the first year (2011) and the second year (2012). Under this condition, soluble protein content and vitamin C of pepper was significantly higher than the control. Compared to spraying clear water，foliar spraying copper fertilizer significantly increased copper concentration in the pepper plant. Meanwhile，the active oxygen that was produced by copper based foliar fertilizers leaded to an increase of superoxide dismutase (SOD), peroxidase (POD) activities. Application of CBFF decreased the catalase (CAT) activity and malondialdehyde (MDA) content. The results indicate that appropriate combined fertilization management can increase micronutrients content in peppers and improve the yield and nutrition quality of peppers.