Abstract

Peach (Prunus persica L. Batsch) is a climacteric export fruit with high economic and commercial value for Chile. During peach development, there are physiological changes induced by a strict phytohormonal control that can alter the final quality of the fruit. Physiological evidence in fruit trees suggests that exogenous application of phytohormone cytokinin could delay the maturation process in the fruit. However, the molecular mechanisms involved in cytokinin effect on peach are barely known. To address this question, we exogenously applied cytokinin to peach fruit in both field (TDZ) and laboratory (trans-zeatin) settings at maturation stage. Later, by using bi-directional blast analysis we selected ripening-related genes that were potentially regulated by cytokinin in peaches. We then performed bioinformatic and gene expression analyses in order to gain insight into these novel set of genes. Through this approach, we identified 18 genes that express differentially under cytokinine treatment, 17 of which exhibited cis-responsive elements to cytokinin in their regulatory region. Among them, we identified “polygalacturonase”, “auxin-responsive protein IAA”, “expansine” and “gibberellin 2-beta-dioxygenase 4”, related to the maturation of the peach fruit. Thus, by performing cytokinine treatments to peach fruit under laboratory and field work, we identified a set of novel cytokinin-responsive genes in peach fruit related to maturation in peach fruits. CONICYT Fondecyt/Regular N°1121021 CONICYT-PCHA/Doctorado Nacional/2014-21140426