Publications by authors named "Delrot S"

Sugar transport plays a pivotal role in determining the productivity of plants and their capacity to act as carbon sinks. In the major fruit crop grapevine (Vitis vinifera L.), the transporter gene V.

View Article and Find Full Text PDF

Most of the carbon found in fruits at harvest is imported by the phloem. Imported carbon provide the material needed for the accumulation of sugars, organic acids, secondary compounds, in addition to the material needed for the synthesis of cell walls. The accumulation of sugars during fruit development influences not only sweetness but also various parameters controlling fruit composition (fruit "quality").

View Article and Find Full Text PDF

Anthocyanin composition is responsible for the red colour of grape berries and wines, and contributes to their organoleptic quality. However, anthocyanin biosynthesis is under genetic, developmental and environmental regulation, making its targeted fine-tuning challenging. We constructed a mechanistic model to simulate the dynamics of anthocyanin composition throughout grape ripening in Vitis vinifera, employing a consensus anthocyanin biosynthesis pathway.

View Article and Find Full Text PDF

Anthocyaninless (white) instead of black/red (coloured) fruits develop in grapevine cultivars without functional VviMYBA1 and VviMYBA2 genes, and this conditions the colour of wines that can be produced. To evaluate whether this genetic variation has additional consequences on fruit ripening and composition, we performed comparisons of microenvironment, transcriptomics, and metabolomics of developing grapes between near-isogenic white- and black-berried somatic variants of Garnacha and Tempranillo cultivars. Berry temperature was as much as 3.

View Article and Find Full Text PDF

We elucidate grapevine evolution and domestication histories with 3525 cultivated and wild accessions worldwide. In the Pleistocene, harsh climate drove the separation of wild grape ecotypes caused by continuous habitat fragmentation. Then, domestication occurred concurrently about 11,000 years ago in Western Asia and the Caucasus to yield table and wine grapevines.

View Article and Find Full Text PDF

To optimize vineyard management practices to adapt viticulture to climate change, knowledge of the regulation mechanism of metabolite accumulation under carbon source limitation and abscisic acid (ABA) application in grapes should be deepened. Here, carbon source limitations were imposed by reducing leaf area from 12 to 2 leaves per vine (at pea sized stage, - 2L-P; or one week prior to veraison - 2L-V) and phloem girdling between the second and third leaf from bottom to top (one week prior to veraison - 12L-girdling) were compared for their effects on berry composition. All three modalities significantly reduced sugar, anthocyanin and ABA content in comparison with berries under sufficient carbon supply (12 leaves per vine - 12L), with 2L-V being the greatest.

View Article and Find Full Text PDF

In ripening grape (Vitis sp.) berries, the combination of rapid sugar import, apoplastic phloem unloading, and water discharge via the xylem creates a potential risk for apoplastic sugar to be lost from the berries. We investigated the likelihood of such sugar loss and a possible sugar retrieval mechanism in the pedicels of different Vitis genotypes.

View Article and Find Full Text PDF

Twelve polyphenols from three distinct families (dihydroflavonols, flavan-3-ols, and flavanones) were studied as potential substrates of anthocyanidin synthase from (ANS). Only flavan-3-ols of (2,3) configuration having either a catechol or gallol group on ring B are accepted as substrates. Only dihydroflavonols of (2,3) configuration are accepted as substrates, but a catechol or gallol group is not mandatory.

View Article and Find Full Text PDF

Perennial woody plants undergo a period of dormancy from the beginning of autumn until the end of spring. Whereas the molecular and physiological events that characterize dormancy release of buds have been described in detail, those occurring in woody tissues underneath the buds are mostly unknown. To bridge this gap, the mRNA populations of cane segments located underneath the bud were analyzed at bud dormancy (E-L 1) and at bud burst (E-L 4).

View Article and Find Full Text PDF

Auxin is a key phytohormone that modulates fruit formation in many fleshy fruits through the regulation of cell division and expansion. Auxin content rapidly increases after pollination and the manipulation in its levels may lead to the parthenocarpic development. ln Vitis vinifera L.

View Article and Find Full Text PDF
Article Synopsis
  • The study examines the anthocyanin accumulation patterns in two teinturier variants of the white-fleshed grape 'Gamay', revealing differences particularly in 'Gamay Fréaux'.
  • While most red grape varieties accumulate anthocyanins in the skin only, 'Gamay Fréaux' accumulates them early and in both skin and pulp, but with lower sugar levels.
  • The findings suggest a unique relationship between sugar and anthocyanin accumulation in 'Gamay Fréaux', providing insights into grape metabolism and potential mechanisms for further research.
View Article and Find Full Text PDF

Potassium (K) nutrition is of relevant interest for winegrowers because it influences grapevine growth, berry composition, as well as must and wine quality. Indeed, wine quality strongly depends on berry composition at harvest. However, K content of grape berries increased steadily over the last decades, in part due to climate change.

View Article and Find Full Text PDF

Background: Grapevine is a crop of major economic importance, yet little is known about the regulation of shoot development in grapevine or other perennial fruits crops. Here we combine genetic and genomic tools to identify candidate genes regulating shoot development in Vitis spp.

Results: An F2 population from an interspecific cross between V.

View Article and Find Full Text PDF

Background: Grape berry ripening is influenced by climate, the main component of the "terroir" of a place. Light and temperature are major factors in the vineyard that affect berry development and fruit metabolite composition.

Results: To better understand the effect of "place" on transcript abundance during the late stages of berry ripening, Cabernet Sauvignon berries grown in Bordeaux and Reno were compared at similar sugar levels (19 to 26 °Brix (total soluble solids)).

View Article and Find Full Text PDF

Climate change scenarios predict an increase in mean air temperatures and in the frequency, intensity, and length of extreme temperature events in many wine-growing regions worldwide. Because elevated temperature has detrimental effects on berry growth and composition, it threatens the economic and environmental sustainability of wine production. Using Cabernet Sauvignon fruit-bearing cuttings, we investigated the effects of high temperature (HT) on grapevine berries through a label-free shotgun proteomic analysis coupled to a complementary metabolomic study.

View Article and Find Full Text PDF

Anthocyanidin synthase from Vitis vinifera ( VvANS) catalyzes the in vitro transformation of the natural isomer of leucocyanidin, 2 R,3 S,4 S- cis-leucocyanidin, into 2 R,4 S-flavan-3,3,4-triol ([M + H], m/ z 323) and quercetin. The C-hydroxylation product 2 R,4 S-flavan-3,3,4-triol is first produced and its C,C-dehydration product is in tautomeric equilibrium with (+)-dihydroquercetin. The latter undergoes a second VvANS-catalyzed C-hydroxylation leading to a 4-keto-2 R-flavan-3,3-gem-diol which upon dehydration gives quercetin.

View Article and Find Full Text PDF

Grafting has been utilised for at least the past 7000 years. Historically, grafting has been developed by growers without particular interest beyond the agronomical and ornamental effects, and thus knowledge about grafting has remained largely empirical. Much of the commercial production of fruit, and increasingly vegetables, relies upon grafting with rootstocks to provide resistance to soil-borne pathogens and abiotic stresses as well as to influence scion growth and performance.

View Article and Find Full Text PDF

The growth of fleshy fruits is still poorly understood as a result of the complex integration of water and solute fluxes, cell structural properties, and the regulation of whole plant source-sink relationships. To unravel the contribution of these processes to berry growth, a biophysical grape (Vitis vinifera L.) berry growth module was developed and integrated with a whole-plant functional-structural model, and was calibrated on two varieties, Cabernet Sauvignon and Sangiovese.

View Article and Find Full Text PDF

The elucidation of the molecular mechanisms of starch synthesis and mobilization in perennial woody tissues is of the utmost scientific and agricultural importance. Starch is the main carbohydrate reserve in plants and is fundamental in human nutrition and several industrial processes. In leaves, starch accumulated during the day is degraded throughout the night and the resulting sugars, glucose and maltose, are exported to the cytosol by the specialized transmembrane translocators pGT and MEX, respectively.

View Article and Find Full Text PDF
Article Synopsis
  • Anthocyanin biosynthesis in plants is influenced by environmental factors like light and water, as well as nutrient availability, particularly nitrogen levels.
  • Research has shown that low nitrogen can boost anthocyanin production, suggesting that a high carbon-to-nitrogen ratio may lead to an excess of energy in plant cells.
  • Using grapevine cells as a model, a study demonstrated that under low nitrogen conditions, central metabolic fluxes decreased while those in the flavonoid pathway increased, supporting the idea that anthocyanin production helps plants manage energy excess.
View Article and Find Full Text PDF

The intra-varietal genetic diversity of grapevine (Vitis vinifera L.) may be exploited to maintain grape quality under future warm conditions, which may alter grape berry development and composition. The present study assesses the effects of elevated temperature on the development of berry, grape composition and anthocyanins:sugars ratio of thirteen clones of V.

View Article and Find Full Text PDF

Background And Aims: Predicting both plant water status and leaf gas exchange under various environmental conditions is essential for anticipating the effects of climate change on plant growth and productivity. This study developed a functional-structural grapevine model which combines a mechanistic understanding of stomatal function and photosynthesis at the leaf level (i.e.

View Article and Find Full Text PDF

How rootstocks contribute to the control of scion transpiration under drought is poorly understood. We investigated the role of root characteristics, hydraulic conductance and chemical signals (abscisic acid, ABA) in the response of stomatal conductance (gs) and transpiration (E) to drought in Cabernet Sauvignon (Vitis vinifera) grafted onto drought-sensitive (Vitis riparia) and drought-tolerant (Vitis berlandieri × Vitis rupestris 110R) rootstocks. All combinations showed a concomitant reduction in gs and E, and an increase in xylem sap ABA concentration during the drought cycle.

View Article and Find Full Text PDF

In many fruit species, including grapevine, grafting is used to improve scion productivity and quality and to adapt the plant to environmental conditions. However, the mechanisms underlying the rootstock control of scion development are still poorly understood. The ability of rootstocks to regulate nitrogen uptake and assimilation may contribute to this control.

View Article and Find Full Text PDF