GiESCO 2019 banner
IVES 9 IVES Conference Series 9 GiESCO 9 GiESCO 2019 9 A few observations on double sigmoid fruit growth

A few observations on double sigmoid fruit growth

Abstract

Context and purpose ‐ Many fleshy fruit, including the grape berry, exhibit a double‐sigmoid growth (DSG) pattern. Identification of the curious DSG habit has long been attributed to Connors’ (1919) work with peaches. Connors’ description of a three‐stage pattern consisting of two growth stages (Stage I and Stage III) separated by a rest period (Stage II) has become textbook material. The growth of grapes was described similarly by Winkler and Williams (1936), Nitsch et al. (1960), and most subsequent authors. Prior to Connors, grape berry development was described as a two‐stage process, in French periode herbacee and periode maturation, but this description refers to fruit ripening and has little or nothing to do with growth.

Material and Methods ‐ A review of grape literature reveals that the characteristic DSG habit was reported several times prior to Connors’ discovery in peaches. Analyses of berry size, turgor, firmness, and composition during Stage II and into Stage III are interpreted in the context of the growth habit.

Results ‐ It will be argued that one researcher in particular, Carl Neubauer, should be credited with the discovery of DSG and its description as a three‐stage phenomenon in fleshy fruits. It is widely reported that DSG in fleshy fruit is a consequence of within‐fruit partitioning (to endocarp or seed rather than pericarp/flesh). However, DSG is observed in berry dry weight and in seedless berries, which negate the common explanations. Thus, one hundred‐fifty years later, the nature of double‐sigmoid growth is still not understood. It is the resumption of rapid growth that is most curious. Various lines of evidence from our studies suggest that a suite of physiological changes during Stage II lead to the transition from Stage II lag phase to Stage III growth, paradoxically implicating a role of low cell turgor. Turgor declines and berries soften during Stage II. These changes occur in conjunction with increased apoplastic solutes and ABA, followed by increased sugar influx and upregulation of cell wall loosening enzymes. Because growth increases in the face of very low turgor, Stage III growth is hypothesized to result from cell wall loosening or even wall degradation without addition of new wall material.

DOI:

Publication date: June 19, 2020

Issue: GiESCO 2019

Type: Article

Authors

Mark MATTHEWS

Dept. of Viticulture and Enology, Univ. California-Davis, Davis, CA 95616

Contact the author

Keywords

berry, fruit, growth, water relations, turgor, cell wall, ABA

Tags

GiESCO 2019 | IVES Conference Series

Citation

Related articles…

Managing extraction of colour, tannin and methoxypyrazines in Pinot noir grapes treated by leaf removal

Managing extraction of tannins and green aroma compounds attributed from methoxypyrazines in winemaking is crucial for producing high quality Pinot noir wine. This study1 investigated the impact of leaf removal on concentrations of anthocyanins, tannins, and methoxypyrazines in Pinot noir grapes and resultant wines.

Development of a strategy for measuring fruity aroma potential in red wine

Levels of esters derived from substituted acids increase during the first years of aging and some of them are strongly involved in red wine fruity aromatic expression.

Untargeted metabolomics analyses to study taste-active compounds released during post-fermentation maceration of wine

The sensory properties of a wine depends on its colours, aromas and flavors. Regarding red wines, the gustatory part consists of the acid, bitter and sweet tastes

Analysis of volatile composition of interaction between the pathogen E. necator and two grapevine varieties

Volatile organic compounds (VOCs) are emitted by nearly all plant organs of the plants, including leaves. They play a key role in the communication with other organisms, therefore they are involved in plant defence against phytopathogens. In this study VOCs from grapevine leaves of two varieties of Vitis vinifera infected by Erysiphe necator were analysed. The varieties were selected based on their susceptibility to pathogen, Kishmish Vatkana has the Ren1 resistance gene and Zamarrica showed high susceptibility in previous trials.

From a local to an international scale: sensory benchmarking of PDO wines. Quincy and Reuilly PDO wines (Sauvignon blanc) as a case study (France)

In a collective marketing strategy, the Protected Designation of Origin (PDO) can be used as a quality indicator. To highlight terroir specificities, it is useful to know how the wines are positioned on the local, national or international market from a sensory point of view. This is especially true for a comparison of varietal wines (e.g. Sauvignon blanc). We focus on the case of two closed Loire Valley PDO (France): Quincy and Reuilly. Three distinct tastings were organized. Firstly, at the local level comparing the 2 PDO (11 and 9 wines, 17 professional assessors); secondly at a regional level adding 3 closed PDO: Menetou-Salon, Sancerre and Pouilly-Fumé (3 wines per PDO, 16 assessors) and thirdly at an international level comparing these 5 PDO with Sauvignon Blanc wines coming from South Africa, New Zealand and Chile (1 to 3 wines per PDO, 19 assessors). All the wines were from the 2019 vintage and were considered to have a traditional elaboration process without contact with oak. A sensory descriptive analysis was performed using an aroma wheel allowing to combine a Check-All-That-Apply methodology, often used in sensory benchmarking, with a hierarchical structuration of the attributes. The aim is to facilitate data acquisition in a professional context without common training, to consider the hierarchical relationships among the attributes during the data analysis and to be able to characterize wines with a large range of sensorial variability. We use univariate, multivariate and clustering analyses. Similarities and differences between Quincy and Reuilly PDO wines and other Sauvignon blanc wines were identified. Specific attributes can distinguish the two PDO and different proximities exist with other local PDO, while clear differences were observed compared to international wines. Our study contributes to propose and discuss a method to do a wine sensory benchmarking highlighting sensory specificities linked to origin.