Non-target metabolomics and expression analysis for studying the modulation endodormancy release in peach flower buds

During winter, Prunus species, like peach (Prunus persica (L.) Batsch), enter into a protector state, which allow them to survive the adverse conditions. This state is known as endodormancy and it starts in the early autumn, finishing after the accumulation of a certain quantity of chill. These chill requirements are specific of each cultivar and they must be fulfilled for a proper flowering and harvest. In the last decades, climate change is causing more frequent warm winters, where chilling is not properly accumulated. Thus, in mild-winter areas, different agrochemicals are applied to high-chilling requirement cultivars to counteract the lack of chilling. In this work, we treated, in three different years, the Carioca peach cultivar (intermediate chilling requirements) with the three following combination of agrochemicals: Syncron (R) + Nitroactive (R), Broston (R) + Nitroactive (R) and Erger (R) + ActiveErger (R). To study the effects of these agrochemicals in endodormancy release, we performed a non-target metabolomic analysis using an UPLC-QToF (ultraperformance liquid chromatography quadrupole time of flight). This analysis showed significant variations in some metabolites related with several metabolic groups, such as phospholipids and metabolites from the biosynthesis of ABA. We hope that our results in peach, the Prunus species reference, will help to understand the endodormancy release process in these species, and in other perennial plants.