Role of hydrogen cyanamide (HC) in grape bud dormancy release: proteomic approach.

In the present study, we identified changes in protein expression patterns of grapevine buds when treated with hydrogen cyanamide (HC). HC induced a shift of more than 2-folds in the expression of 1250 proteins out of approximately 7000 detected proteins. The majority of the differentially expressed proteins (DEPs) were localized in the chloroplast (419) and cytoplasm (347). Most of the detected DEPs were linked with energy metabolism, redox activity, hormone, and stress signaling. Particularly, the DEPs associated with defense and sugar metabolism showed significantly higher expression in HC-treated buds. Kyoto encyclopedia of genes and genomes (KEGG) analysis revealed significant enrichment for circadian rhythm, ribosome, and metabolic pathways. Moreover, the antioxidant activity of peroxidase (POD) increased at initial stages but declined at later stages (18 days post-treatment). This study identified several dormancy-related proteins that regulated signaling, as well as metabolic pathways upon HC application. The outcome of this study provides insights into the role of HC in dormancy release for grapevine production, hence useful to alleviate yield losses in mild winter regions.