S11 - Session P2 - DNA hypomethylation induced by 5-azacytidine promotes dormancy release in Prunus Avium L

Authors: Esteban Soto *, Erica Fadon, Eduardo Fernandez, Thorsten Kraska

Temperate fruit trees require sustained exposure to low temperatures during winter dormancy for growth resumption in spring. Dormancy is caused by endogenous factors, including genetics and epigenetics characteristics. Global warming is causing increases in winter temperature, which are expected to increasingly impact on tree dormancy in the future. Likely consequences of this are incomplete dormancy release, which may severely reduce fruit production and provoke economic losses. The study of the mechanisms regulating dormancy and dormancy release has therefore emerged as an urgent topic for the fruit industry. Previous studies on proteomic, transcriptomic, and genomic aspects of dormancy have indicated the importance of epigenetic mechanisms for dormancy regulation. DNA methylation (cytosine methylation) has been shown to plays a key role in regulating the expression of dormancy-associated genes. Based on these findings, we hypothesize that dormancy can be artificially altered by the external application of 5-azacytidine (5-azaC). This product is an analog of cytosine which can be incorporated in DNA by substituting for cytosine. In brief, 5-azaC induce hypomethylation of genomic DNA by blocking the action of methyltransferases through covalent binding. We aim to evaluate dormancy release with different applications of 5-azaC during dormancy. We design a number of treatments with different concentrations of the product and application times on sweet cherry cultivars with different chill requirements.