Modelling variety-dependent dynamics of soluble solids and water in berries ofVitis vinifera

Abstract

Background and Aims: We modelled the dynamics of soluble solids, largely sugars, and water in 12 Vitis vinifera varieties. Emphasis was placed on maximum concentration of soluble solids (Smax) and time of maturity for their viticultural importance. Methods and Results: We measured the concentration of soluble solids and water at weekly intervals during berry ripening. The dynamics of concentration of soluble solids was characterised with a sigmoid model, whereas water concentration was characterised with a concentration–response type curve. Scaling exponents for soluble solids (αs) and water (αw) were calculated as the slope of the log–log regression between amount of soluble solids or water per berry and berry fresh mass. Smax ranged from 27.1% in Shiraz to 21.2% in Riesling, was associated with both αw and αs, and was largely unrelated to source size (leaf area, pruning weight, light interception), source activity (stomatal conductance), sink size (yield components) and source : sink ratios. The time of maturity ranged from 26 January in Verdelho to 27 February in Crimson Seedless, and was an inverse function of the rate of change in concentration of soluble solids, which was in turn a direct function of stomatal conductance. Conclusions: Traits related to carbon assimilation influenced time of maturity, but their link with maximum concentration of soluble solids in berries was not evident. Significance of the Study: Quantitative models of accumulation of soluble solids are presented that provide a baseline for comparisons among varieties.

Effect of Berry Weight and its Components on the Contents of Sugars and Anthocyanins of Three Varieties of Vitis vinifera L. under Different Water Supply Conditions

“…The water content in the berries was reported as inversely proportional to the content of sugars by Liu et al (2007) and confirmed by Sadras et al (2008). These patterns in water dynamics may differ depending on the variety.…”

“…This result explains the higher sugar content in Tannat berries. Some authors hypothesise this to be due to genetic causes (Edson et al, 1995;Gomez del Campo et al, 2005;Liu et al, 2007;Sadras et al, 2008).…”

“…Variety is one of the major factors determining the difference in size and composition of the berry as a result of specific genetic characteristics associated with growth and the relative proportion of the components (flesh, seeds and skin) and their relationships (Matthews & Nuzzo, 2007;Constantini et al, 2008;Attia et al, 2010;Barbagallo et al, 2011;Dai et al, 2011;Nicolas et al, 2013). Genetics determines composition and has an influence on the ability of the variety to accumulate compounds, on the way in which photosynthetic products are distributed within the plant and on their influence on secondary metabolism (Edson et al, 1995;Gomez del Campo et al, 2005;Liu et al, 2007;Sadras et al, 2008;Dai et al, 2011). Among the components of the berry, flesh represents the largest proportion of weight and is the place where most sugars accumulate (Matthews & Nuzzo, 2007;Barbagallo et al, 2011).…”

Ecophysiological, Genetic, and Molecular Causes of Variation in Grape Berry Weight and Composition: A Review

“…This constitutes a first step toward an integrated approach of grapevine berry physiology. More efforts are needed, and a better understanding of berry metabolism and composition, and of their variations, will require further progress in systems biology and modeling of fruit growth and metabolism (Dai et al 2010, Génard et al 2010, Sadras et al 2008). …”

Influence of retained node number on Sauvignon Blanc grapevine phenology in a cool climate

“…As proposed by Sadras et al (2008), ripening was considered to follow a sigmoidal curve. As proposed by Sadras et al (2008), ripening was considered to follow a sigmoidal curve.…”