Factors controlling inflorescence primordia formation of grapevine: their role in latent bud fruitfulness? A review

Abstract

The grapevine (Vitis vinifera L.) is a widely cultivated species of major economic importance for wine production. The quality and quantity of grapes are criteria of prime importance to the wine industry, but they are highly variable from year to year. Unlike many perennial plants, cluster formation unfolds in two seasons: season 1 takes place in the bud until dormancy, and season 2 starts after budbreak in the following year. Season 1 corresponds to the initiation and differentiation of inflorescence primordia, controlled by many exogenous and endogenous factors, which explains up to 60% seasonal variation in yield. Season 2 consists of flowering and fruit development, which explains, respectively, 30% and 10% of seasonal variation in yield. It is therefore essential to understand the impact of these factors to better control the yield. This review aims to summarize past and present knowledge concerning the physiology of latent buds relating to their fruitfulness, and to assess the impact of environmental, hormonal, and regulation factors on the final yield. Avenues of further research to understand physiological, biochemical and molecular regulatory mechanisms of initiation and differentiation of clusters will be then proposed.