Differential expression of allene oxide synthase (AOS), and jasmonate relationship with ethylene biosynthesis in seed and mesocarp of developing peach fruit

► JA involvement in developmental processes includes seed germination and fruit development and ripening. ► Allene oxide synthase (AOS) is shown to be differentially expressed in seed (embryo and cotyledons) and mesocarp of peach fruit according to the developmental stage. ► AOS transcript abundance and jasmonic acid levels peak at S1 and S4. ► In early developmental stages MJ stimulates its own and the ethylene biosynthetic gene expression in both the seed and mesocarp, while, later, the effect is differential in the two parts of the fruit.