Effects of plant hormones on main health-promoting compounds and antioxidant capacity of Chinese kale

The effects of methyl jasmonate (MeJA), Ethrel (ETH), 1-methylcyclopropene (1-MCP) and salicylic acid (SA) treatments on contents of glucosinolates, vitamin C, total phenolics, carotenoids and chlorophyll, as well as antioxidant capacities were investigated in Chinese kale. MeJA treatment induced significant increase in the concentrations of glucobrassicin, neoglucobrassicin and total indole gulcosinolates, while SA treatments led to predominant enhancement of 4-methoxyglucobrassicin and aliphatic glucosinolates. The total phenolic content and the antioxidant capacities were remarkably increased by all the hormone treatments. In addition, the effect of SA treatments varied with different handling methods. Spraying on the aboveground parts is a better SA treatment approach than root irrigation. These results demonstrated that plant hormones, especially the MeJA and SA, significantly increased the contents of main health-promoting compounds, and enhanced the antioxidant capacities of Chinese kale. (C) 2012 Elsevier Ltd. All rights reserved.