LAUSR

Abstract The Japanese apricot (Prunus mume Sieb. et Zucc.) is a typical climacteric fruit which loses commercial value during processing when the surface color turns yellow. In our study, treatment with nordihydroguaiaretic acid (NDGA), an abscisic acid (ABA) synthesis inhibitor, delayed the increase of ethylene and decrease of firmness towards ripening, and retarded the degradation of chlorophyll and the accumulation of carotenoids including β-carotene and lycopene through the expression of PmCHL (coding for chlorophyllase), PmGGPPS (coding for geranylgeranyl diphosphate synthase), PmPDS (coding for phytoene desaturase), PmPSY (coding for phytoene synthases), and PmLCYB (coding for lycopene beta-cyclase). NDGA inhibited the ABA synthesis through PmNCED1 and these results show that ABA may affect the ripening of the Japanese apricot by influencing ethylene production and the expression of PmACS (coding for ACC synthase), PmACO (ACC oxidase) and the ethylene-responsive gene PmERF (ethylene-responsive transcription factor), and thus that ethylene and ABA may interact during fruit ripening in climacteric fruit.