Synergism exists between ethylene and methyl jasmonate in artificial light-induced pigment enhancement of ‘Fuji’ apple fruit peel

Abstract

The pigment content of detached ‘Fuji’ apple peel was characterized in fruit exposed to ethylene and/or treated with methyl jasmonate (MJ), then irradiated with ultraviolet (UV)/white light. Peel pigments were analyzed using reversed-phase high-performance liquid chromatography coupled with scanning UV–vis absorbance detection. Treatment with MJ alone enhanced anthocyanin content, including idaein, the major anthocyanin in apple fruit. Anthocyanin content was further enhanced by treatment with MJ + ethylene. Treatment with the ethylene action inhibitor 1-MCP plus MJ reduced red coloration compared with MJ alone. Treatment with ethylene or 1-MCP alone, or ethylene + 1-MCP had no effect on anthocyanin accumulation. Production of hyperin, the major quercetin glycoside in peel tissue, was enhanced by MJ and inhibition of ethylene action with 1-MCP enhanced the impact of MJ. 1-MCP with or without MJ increased phloridzin content. Chlorogenic acid synthesis was enhanced following treatment with MJ and/or ethylene, however, treatment with 1-MCP alone or 1-MCP plus MJ resulted in reduced chlorogenic acid content. β-Carotene synthesis increased following MJ plus ethylene, but was not enhanced by MJ or ethylene alone. The results indicate synergistic or additive responses between ethylene and MJ exists for regulation of apple peel pigment synthesis pathways.