High temperature acclimation of berry ripening in Muscat Hamburg grapevine cultivar

Póster presentado en el IX International Symposium on Grapevine Physiology and Biotechnology, celebrado en La Serena (Chile) del 21 al 26 de abril de 2013.Berry organoleptic properties are highly influenced by ripening environmental conditions. In this study, we used grapevine fruiting cuttings to follow berry ripening under different conditions of temperature and irradiation. Berries ripened at higher temperatures showed reduced anthocyanin accumulation and hastened ripening leading to characteristic malic acid and total acidity drop. The GrapeGen GeneChip combined with a newly developed GrapeGen 12Xv1 MapMan version were used for the functional analysis of berry transcriptomic differences after two weeks treatments from veraison onset. These analyses revealed the establishment of a thermotolerance response dominated by the induction of HSP chaperones and the repression of transmembrane transporter encoding transcripts. The thermotolerance response was coincident with up-regulation of ERF subfamily transcription factors and increased ABA levels suggesting their participation in the acclimation response maintenance. Lower expression of amino acid transporter encoding transcripts at high temperature was able to balance amino acid content suggesting a transcriptional compensation of temperature effects on protein and membrane stability to allow completion of berry ripening. By contrast, the lower anthocyanin accumulation and higher malate metabolization measured under high temperature might partly result from imbalance in the expression and function of their specific transmembrane transporters.Acknowledgments: Project GrapeGen (Fundación Genoma España).Peer Reviewe