Firmness and grape berry maturation. Definition of different rheological parameters during the ripening

OENO One ◽  
1997 ◽  
Vol 31 (3) ◽  
pp. 127 ◽  
Author(s):  
Jean-Pierre Robin ◽  
Philippe Abbal ◽  
Jean-Michel Salmon

<p style="text-align: justify;">Mechanical properties of Shiraz and Gamay grape berries were studied in relation with their maturity state using the Penelaup<sup>TM</sup> rheometer. The analysis of the constrains registered during berry crushing with the flat tool of the device, up to the pellicular tearing, allowed the definition of different rheological parameters and the characterisation of mechanical behaviour of grape and its evolution with the degree of ripening. The analysis of the deformability curves shows, independently of the cultivar, that berry behaviour is not elastical except for some berries at the beginning and at the end of the ripening. This behaviour can be characterised by two indexes expressing the curvature sense of deformability curves, the curvature degree in a way reflecting the turgescence state of the grape. Berry firmness was also considered in two different ways: the initial firmness which represents the elasticity coefficient of the fruit at the beginning of the deformation, and the bursting firmness which can be considered as the pellicular elasticity coefficient. Others parameters, as the pellicular strength which can be expressed from the value of the displacement at berry bursting and the energy used for the deformation were also defined. The evolution of these different parameters during ripening confirms that berry softening at the véraison time depends on the cultivar and on environmental conditions as the vintage. The analysis of the evolutions also indicates that pellicular strength is maximum at this crucial period of berry development.</p>

2018 ◽  
Author(s):  
Andrea Minio ◽  
Mélanie Massonnet ◽  
Rosa Figueroa-Balderas ◽  
Amanda M. Vondras ◽  
Barbara Blanco-Ulate ◽  
...  

AbstractTranscriptomics has been widely applied to study grape berry development. With few exceptions, transcriptomic studies in grape are performed using the available genome sequence, PN40024, as reference. However, differences in gene content among grape accessions, which contribute to phenotypic differences among cultivars, suggest that a single reference genome does not represent the species’ entire gene space. Though whole genome assembly and annotation can reveal the relatively unique or “private” gene space of any particular cultivar, transcriptome reconstruction is a more rapid, less costly, and less computationally intensive strategy to accomplish the same goal. In this study, we used single molecule-real time sequencing (Iso-Seq) to sequence full-length cDNA and reconstruct the transcriptome of Cabernet Sauvignon berries during berry ripening. In addition, Illumina short reads from ripening berries were used to error-correct low-expression isoforms and to profile isoform expression. By comparing the annotated gene space of Cabernet Sauvignon to other grape cultivars, we demonstrate that the transcriptome reference built with Iso-Seq data represents most of the expressed genes in the grape berries and includes 1,501 cultivar-specific genes. Iso-Seq produced transcriptome profiles similar to those obtained after mapping on a complete genome reference. Together, these results justify the application of Iso-Seq to identify cultivar-specific genes and build a comprehensive reference for transcriptional profiling that circumvents the necessity of a genome reference with its associated costs and computational weight.


2019 ◽  
Vol 13 ◽  
pp. 01001
Author(s):  
Marianna Fasoli ◽  
Chandra L. Richter ◽  
Sara Zenoni ◽  
Marco Sandri ◽  
Paola Zuccolotto ◽  
...  

The progress of the grapevine genomics and the development of high-throughput technologies for gene expression analysis stimulated the investigation of the physical, biochemical and physiological changes of grape berry growth and maturation at transcriptomic level. The molecular information generated in the last decade is however still fragmented since it relies upon detailed analysis of few stages and thus lacks continuity over grape development. To identify the molecular events associated with berry development at a higher temporal resolution and define a transcriptomic map, we performed RNA-seq analysis of berry samples collected every week from fruit-set to maturity in Pinot noir and Cabernet Sauvignon for three consecutive years, resulting in 219 samples. Using the most variable portion of the transcriptome, we built a preliminary transcriptomic model of berry development based on the Cabernet Sauvignon samples. The Pinot noir samples were then aligned onto this preliminary ripening map to investigate its performance in describing the development of another grape variety. A further step for testing the model was the projection of RNA-seq samples of fruit development of five red-skin Italian cultivars. For all these surveys, the transcriptomic route allowed a precise definition of the progression of berry development during both formation and ripening phases.


2021 ◽  
Vol 8 (1) ◽  
Author(s):  
Ben-Min Chang ◽  
Markus Keller

AbstractThe skin protects a fruit from environmental stresses and supports the fruit’s structure. Failure of the skin leads to fruit splitting and may compromise commercial production for fruit growers. The mechanical properties of the cuticle and skin cell walls might influence the splitting susceptibility of fleshy fruits. Thin shell theory and fracture mechanics were utilized in this study to target the potential factors contributing to splitting susceptibility. The study analyzed the structure of the cuticle and epidermis in ripening grape berries and examined the temporal dynamics of berry splitting. Cuticular waxes were partially removed, and skin cell walls were manipulated using wall stiffening and loosening solutions that altered reactions involving hydrogen peroxide. A more than twofold difference in cuticle thickness among grape cultivars did not account for their differences in splitting resistance. However, while removing predominantly epicuticular wax did not alter the berries’ splitting resistance, their surface appearance and increasing yield strength following partial wax removal support the notion that cuticular waxes contribute to berry mechanical properties. Immersing berries in H2O2-based cell wall loosening solutions increased the splitting probability and accelerated berry splitting, whereas cell wall stiffening solutions decreased the splitting probability and delayed berry splitting. These results showed that both cuticle and skin cell walls contribute to the mechanical properties of grape berries and to their splitting resistance. The results also suggest that the two current explanations for fruit splitting, the critical turgor model and the zipper model, should be viewed as complementary rather than incompatible.


1978 ◽  
Vol 5 (4) ◽  
pp. 415 ◽  
Author(s):  
WJS Downton ◽  
BR Loveys

Changes in the chemical composition of developing Cabernet Sauvignon berries from salt-treated and low-salt vines were followed. Although salinity advanced the timing of veraison, the sequence of changes in the salt-affected berries remained the same as in berries from control plants, viz. concentrations of abscisic acid and reducing sugar increased before proline, arginine, potassium and chloride increased, and before acidity declined. The contribution of these substances to osmotic changes within developing grape berries is discussed.


2019 ◽  
Vol 47 (4) ◽  
pp. 1194-1205
Author(s):  
Qian ZHA ◽  
Xiao Jun XI ◽  
Yani HE ◽  
Ai Li JIANG

Grapevine is one of the most important fruit-bearing plants worldwide, for which bagging treatments can effectively improve fruit quality. However, the low-light conditions caused by bagging can delay grape berry maturation. Here, we analyzed glucose, fructose, and anthocyanin contents and the expression of sugar and anthocyanin-metabolism pathway genes in the grape berries of two cultivars, ‘Shenhua’ and ‘Shenfeng’, under different bagging treatments. Color development was incomplete in bagged grape berries and their soluble sugar contents were lower than those detected in un-bagged fruits. However, fruit color and SSC could be rapidly restored to normal levels after removing bags. Light affects the accumulation of sugar in grape berries, especially near the maturation period, as well as the contents and compositions of anthocyanins in the skin of grape berries. Although light helps in the accumulation of anthocyanins, significant differences were detected in anthocyanin composition between the two grapevine varieties. In addition, the expressions of myofibroblastic regulatory genes in the anthocyanin pathway were affected by light, and the light-responsive elements elongated hypocotyl 5 and constitutive photomorphogenic 1 acted synergistically to control grape berry coloration. Overall, these results provide a theoretical basis for the maturation mechanism in grape berries.   ********* In press - Online First. Article has been peer reviewed, accepted for publication and published online without pagination. It will receive pagination when the issue will be ready for publishing as a complete number (Volume 47, Issue 4, 2019). The article is searchable and citable by Digital Object Identifier (DOI). DOI link will become active after the article will be included in the complete issue. *********


Foods ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 896
Author(s):  
Ziwen Su ◽  
Xicheng Wang ◽  
Xuxian Xuan ◽  
Zilu Sheng ◽  
Haoran Jia ◽  
...  

In recent years, more and more reports have shown that the miR156-SPL module can participate in the regulation of anthocyanin synthesis in plants. However, little is known about how this module responds to hormonal signals manipulating this process in grapes. In this study, exogenous GA, ABA, MeJA, and NAA were used to treat the ‘Wink’ grape berries before color conversion, anthocyanin and other related quality physiological indexes (such as sugar, aroma) were determined, and spatio-temporal expression patterns of related genes were analyzed. The results showed that the expression levels of VvmiR156b/c/d showed a gradually rising trend with the ripening and color formation of grape berries, and the highest expression levels were detected at day 28 after treatment, while the expression level of VvSPL9 exhibited an opposite trend as a whole, which further verifies that VvmiR156b/c/d can negatively regulate VvSPL9. Besides, VvmiR156b/c/d was positively correlated with anthocyanin content and related genes levels, while the expression pattern of VvSPL9 showed a negative correlation. Analysis of promoter cis-elements and GUS staining showed that VvmiR156b/c/d contained a large number of hormone response cis-elements (ABA, GA, SA, MeJA, and NAA) and were involved in hormone regulation. Exogenous ABA and MeJA treatments significantly upregulated the expression levels of VvmiR156b/c/d and anthocyanin structural genes in the early stage of color conversion and made grape berries quickly colored. Interestingly, GA treatment downregulated the expression levels of VvmiR156b/c/d and anthocyanin structural genes in the early color-change period, but significantly upregulated in the middle color-change and ripening stages, therefore GA mainly modulated grape berry coloring in the middle- and late-ripening stages. Furthermore, NAA treatment downregulated the expression levels of VvmiR156b/c/d and anthocyanin structural genes and delayed the peak expression of genes. Meanwhile, to further recognize the potential functions of VvmiR156b/c/d, the mature tomato transient trangenetic system was utilized in this work. Results showed that transient overexpression of VvmiR156b/c/d in tomato promoted fruit coloring and overexpression of VvSPL9 inhibited fruit coloration. Finally, a regulatory network of the VvmiR156b/c/d-VvSPL9 module responsive to hormones modulating anthocyanin synthesis was developed. In conclusion, VvmiR156b/c/d-mediated VvSPL9 participated in the formation of grape color in response to multi-hormone signals.


2021 ◽  
Vol 9 (1) ◽  
Author(s):  
Mathilde Tiennot ◽  
Davide Iannuzzi ◽  
Erma Hermens

AbstractIn this investigation on the mechanical behaviour of paint films, we use a new ferrule-top nanoindentation protocol developed for cultural heritage studies to examine the impact of repeated relative humidity variations on the viscoelastic behaviour of paint films and their mechanical properties in different paint stratigraphies through the changes in their storage and loss moduli. We show that the moisture weathering impact on the micromechanics varies for each of these pigment-oil systems. Data from the nanoindentation protocol provide new insights into the evolution of the viscoelastic properties dsue to the impact of moisture weathering on paint films.


Insects ◽  
2021 ◽  
Vol 12 (2) ◽  
pp. 169
Author(s):  
Federico Lessio ◽  
Alberto Alma

This paper reviews the existing predictive models concerning insects and mites harmful to grapevine. A brief conceptual description is given on the definition of a model and about different types of models: deterministic vs. stochastics, continuous vs. discrete, analytical vs. computer-based, and descriptive vs. data-driven. The main biological aspects of grapevine pests covered by different types of models are phenology, population growth and dynamics, species distribution, and invasion risk. A particular emphasis is put on forecasting epidemics of plant disease agents transmitted by insects with sucking-piercing mouthparts. The most investigated species or groups are the glassy-winged sharpshooter Homalodisca vitripennis (Germar) and other vectors of Xylella fastidiosa subsp. fastidiosa, a bacterium agent of Pierce’s disease; the European grape berry moth, Lobesia botrana (Denis and Schiffermuller); and the leafhopper Scaphoideus titanus Ball, the main vector of phytoplasmas agents of Flavescence dorée. Finally, the present and future of decision-support systems (DSS) in viticulture is discussed.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Annette Reineke ◽  
Alberto Pozzebon ◽  
Olivia Herczynski ◽  
Carlo Duso

AbstractThe grape berry moth Eupoecilia ambiguella (Lepidoptera: Tortricidae) is causing significant damage to grape berries, however, little is known on population genetics of this lepidopteran pest insect, hindered so far by the lack of suitable molecular markers. Here we report on the development of ten microsatellite markers of which six were used to characterise 21 E. ambiguella populations obtained from two viticultural regions in Germany and Italy. Moths were sampled during two subsequent generations (flights) in the same vineyard as well as in vineyards surrounded by different landscape types. German and Italian populations were genetically differentiated and a significant isolation by distance was evident. No significant divergence was observed among the populations from first or second flight moths, however, inbreeding was higher in first than in second flight populations. Moreover, inbreeding was influenced by habitat composition and complexity of landscape around vineyards, being positively associated with the percentage of area covered by grapevine. Population genetics of E. ambiguella could thus be affected by the presence of alternative host plants in viticultural landscapes, which is important in the light of both insecticide resistance management and sustainable pest management.


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