Inflammatory bowel disease, which encompasses ulcerative colitis and Crohn’s disease, affects millions of people worldwide and is characterized by chronic, relapsing inflammation of the gastrointestinal tract. Current therapies, including corticosteroids, immunosuppressants, and biologics targeting tumor necrosis factor alpha, can be effective but often carry substantial side effects, high costs, and loss of efficacy over time. This therapeutic gap has driven intense interest in natural products, particularly polyphenol-rich plant extracts, that might modulate inflammation with fewer adverse consequences. Grapevine leaves have been used in traditional medicine across the Mediterranean for centuries, valued for their astringent and anti-inflammatory properties, but their potential in intestinal inflammation had remained largely unexplored in rigorous preclinical models.

The research team, led by Houssam Shaib with collaborators including Laura Dosh, Lara Diab, Rana Bou Khalil, and Abdo Jurjus, began by characterizing the phytochemical profile of grapevine leaves collected from Mount Lebanon. Using hydroethanolic extraction, a method that efficiently captures both water-soluble and alcohol-soluble compounds, they quantified the extract’s total phenolic content, condensed tannin levels, and antioxidant reducing power. The results were striking: the extract contained 63.3 milligrams of gallic acid equivalents per gram for total phenolics and 60.8 milligrams of catechin equivalents per gram for condensed tannins, both indicating a densely polyphenol-rich preparation. Reducing power activity, a measure of the extract’s capacity to donate electrons and neutralize reactive species, yielded an EC50 of 121.4 micrograms per milliliter, confirming substantial antioxidant capacity.

These measurements matter because oxidative stress is a central driver of intestinal inflammation. In colitis, infiltrating immune cells generate reactive oxygen species that damage epithelial cells lining the colon, breach the mucosal barrier, and allow luminal bacteria to trigger further immune activation. Polyphenols and condensed tannins can interrupt this cascade at multiple points, scavenging free radicals, chelating pro-oxidant metal ions, and modulating intracellular signaling pathways such as nuclear factor kappa B and mitogen-activated protein kinase, which orchestrate the transcription of inflammatory genes. The chemical profile of the Lebanese grapevine leaf extract therefore suggested it was well equipped to counter the oxidative and inflammatory damage characteristic of colitis.

To test this hypothesis, the researchers induced acute colitis in BALB/c mice using intrarectal administration of 2,4,6-trinitrobenzenesulfonic acid, or TNBS, a widely used haptenizing agent that provokes a T helper cell type 1 and type 17 driven inflammatory response closely mimicking aspects of human Crohn’s disease. TNBS damages the colonic epithelium and renders it immunogenic, unleashing a wave of inflammatory cytokines that recruit immune cells into the gut wall. Following induction, the mice received oral doses of the grapevine leaf extract at different concentrations, allowing the team to assess both efficacy and dose-response relationships.

The disease model performed as expected. TNBS-treated mice displayed marked intestinal inflammation, with increased colon weight reflecting edema and tissue thickening, dense infiltration of inflammatory cells, and visible epithelial damage. At the molecular level, the researchers observed significant upregulation of the genes encoding interleukin-17, interleukin-23, interferon gamma, and transforming growth factor beta, a cytokine signature that maps directly onto the IL-23/IL-17 axis now recognized as a pivotal pathway in inflammatory bowel disease. Biologic drugs targeting IL-17 and IL-23 have shown clinical benefit in patients, underscoring the relevance of this signaling axis as a therapeutic target.

Treatment with the grapevine leaf extract changed the picture dramatically. Mice receiving the extract showed significantly improved clinical signs and attenuated histopathological lesions, with reduced inflammatory cell infiltration and less epithelial injury compared with untreated colitic animals. Most notably, the 300 milligram per kilogram body weight dose demonstrated the strongest immunomodulatory effect, restoring inflammatory cytokine gene expression toward basal levels comparable to those of healthy control mice. This dose-dependent normalization of the IL-17, IL-23, IFN-gamma, and TGF-beta signature suggests that the extract does not merely mask symptoms but actively recalibrates the immune signaling underlying the disease process.

The authors analyzed parametric data using one-way analysis of variance with Tukey’s post hoc test, while non-parametric data such as disease scores and gene expression were evaluated with the Kruskal-Wallis test, providing statistical rigor appropriate to the mixed data types. All animal procedures were approved by the Institutional Animal Care and Use Committee of the American University of Beirut, and plant samples were collected from private land with the landowner’s explicit permission. The work was funded by the Farouk Jabre Grant at the American University of Beirut, and the authors declare no competing interests.

The implications extend beyond the laboratory. Grapevine leaves are an abundant agricultural residue generated in enormous quantities by the wine industry each pruning season, which means a therapeutic extract could be sourced sustainably and inexpensively from material that would otherwise be discarded. This aligns with growing interest in circular economy approaches to nutraceutical and pharmaceutical development, particularly in Mediterranean countries where both viticulture and inflammatory bowel disease intersect. A standardized grapevine leaf extract could, in principle, be developed as a complementary therapy for maintaining remission in inflammatory bowel disease patients or as a preventive agent in at-risk populations, though considerable work remains before such applications.

Important caveats temper the excitement. The study was conducted in an acute mouse model of chemically induced colitis, which, while valuable for dissecting inflammatory mechanisms, does not fully recapitulate the chronic, relapsing nature of human inflammatory bowel disease. Bioavailability of polyphenols and tannins in humans is often limited by poor absorption and rapid metabolism, and effective doses in mice do not translate directly to human dosing. Human clinical trials, chronic disease models, and detailed mechanistic studies identifying the specific active compounds within the extract will all be necessary. Nevertheless, the demonstration that a simple, traditionally used plant extract can restore a disease-driving cytokine profile to healthy baseline levels in vivo is a compelling proof of concept, and it adds grapevine leaves to the expanding pharmacopoeia of natural products under investigation for inflammatory disorders.

Subject of Research: Anti-inflammatory effects of grapevine leaf extract in a mouse model of TNBS-induced colitis

Article Title: Protective anti-inflammatory effects of Vitis vinifera leaf extract against TNBS-induced colitis in mice

Article References: Protective anti-inflammatory effects of Vitis vinifera leaf extract against TNBS-induced colitis in mice. (n.d.). https://doi.org/10.1186/s12906-026-05639-1

Image Credits: AI Generated

DOI: 10.1186/s12906-026-05639-1

Keywords: Vitis vinifera, grapevine leaf extract, colitis, TNBS, inflammatory bowel disease, cytokines, IL-17, IL-23, antioxidants, polyphenols, natural products, mouse model

The story of Tribidrag is itself a tale of scientific detective work. For decades, the identity of Zinfandel was one of the great mysteries of viticulture, with competing claims about whether the variety originated in Italy, where it thrives as Primitivo, or elsewhere in the Mediterranean. Genetic fingerprinting eventually traced the cultivar to Croatia, where it survives under its oldest recorded name, Tribidrag, and where old vines still cling to terraced slopes along the Adriatic coast. Because grapevines are propagated vegetatively, by cuttings rather than seeds, every plant of a given variety is in principle a genetic copy of its parent. Yet over centuries of cloning, somatic mutations accumulate, and growers have selected vines that differ in yield, berry size, sugar accumulation, and acidity. These selected lines, called clones, are the raw material of clonal selection programs that supply nurseries and vineyards worldwide.

The research team, led by Goran Zdunić of the Institute for Adriatic Crops and Karst Reclamation in Split and including collaborators at the University of Zagreb and Yunnan Agricultural University in Kunming, set out to bridge a persistent gap in clonal research. Although previous studies had documented variation among Tribidrag clones both in the vineyard and at the molecular level, no one had systematically connected the two. The question was deceptively simple: if two clones of the same variety look and behave differently, can we find the genetic differences responsible? To answer it, the researchers evaluated productive traits in eight clones over three consecutive growing seasons, measuring yield, yield components, and basic must chemistry, the sugar and acid parameters that determine the character of the resulting wine.

The field data told a clear story of phenotypic divergence. The eight clones varied significantly in productivity and showed significant phenotypic plasticity, meaning their performance shifted from year to year depending on growing conditions. Statistical analysis revealed a significant clone-by-year interaction, confirming that no single clone dominates in every season. Two clones maintained under the Foundation Plant Services collection in California, designated FPS03 and FPS06 and known as Primitivo selections, consistently showed lower productivity, smaller berries, higher sugar content, and lower total acidity in the 2021 and 2022 seasons compared with the Zinfandel 1–24 clone. That latter clone displayed greater productivity in all three years of the study, making it the most reliable performer in the trial. For winemakers, these differences matter enormously: smaller berries with concentrated sugars tend to produce more structured, intense wines, while higher-yielding clones favor volume and freshness.

With the phenotypic landscape mapped, the team turned to the genome. Using short-read whole-genome resequencing, they generated high-coverage sequence data for each of the eight clones and called variants across the entire reference genome of grapevine. The scale of the variation was remarkable. Each sample carried approximately 3.8 million single nucleotide polymorphisms, or SNPs, which are positions where a single DNA letter differs from the reference, along with roughly 300,000 insertions and deletions, known as InDels, where short stretches of sequence are present or absent. That level of variation within a single vegetatively propagated cultivar underscores how much somatic mutation and historical mixing of plant material can accumulate over centuries of clonal transmission. Most of the structural variants were located in intergenic regions, the stretches of DNA between genes, which is consistent with the expectation that purifying selection keeps functional gene sequences relatively stable while neutral variation piles up elsewhere in the genome.

To hunt for signatures of clonal selection, the researchers took a windowed approach, dividing the genome into 100-kilobase segments and counting pairwise SNP differences among the eight clones within each window. This method highlights genomic neighborhoods where particular clones stand out from the rest, suggesting that a mutation or set of mutations arose on a specific vine lineage and was then propagated along with it. The analysis revealed candidate regions that distinguish individual clones, providing a catalog of genomic intervals that future studies can mine for genes influencing berry size, sugar transport, acid metabolism, and other traits of viticultural interest. Because the windows are small enough to pinpoint candidate loci but large enough to be robust to sequencing noise, the approach offers a practical middle ground between whole-genome association studies and targeted candidate-gene sequencing.

Then came the twist. When the researchers performed a principal component analysis on the genome-wide SNP data, the eight clones resolved into three principal genetic clusters. If clonal selection had driven the phenotypic differences, one might expect the low-yielding, sugar-rich Primitivo clones to group together genetically, apart from the productive Zinfandel selections. Instead, the genetic groupings showed no clear geographic association among the samples and, more strikingly, no direct association with the phenotypic or productive traits of individual clones. The clones that look most different in the vineyard are not necessarily the ones that are most different in their DNA, at least not at the resolution of genome-wide SNP patterns. Measurable genetic differentiation is real, but it is not a simple mirror of measurable phenotypic divergence.

This disconnect is not a failure of the study; it is arguably its most valuable finding, and it echoes a pattern seen in other clonally propagated crops. Phenotypic differences among clones can arise from a small number of mutations with large effects, from epigenetic changes such as DNA methylation that whole-genome resequencing of the kind performed here does not capture, from structural rearrangements too large or too complex for short-read sequencing to resolve, or from interactions between genotype and environment that three field seasons, however carefully measured, only begin to sample. The significant clone-by-year interaction observed in the trial reinforces this last point: the same clone can rank differently for yield and must composition depending on the season, so any attempt to link genes to traits must account for environmental noise. The candidate SNP signatures identified in 100-kilobase windows now provide a starting list of genomic regions where deeper investigation, including long-read sequencing, epigenomic profiling, and functional validation, is most likely to pay off.

For the wine industry, the implications are practical as well as scientific. Clonal selection programs rely on the assumption that the clones they distribute are genetically distinct and predictably different in performance. The new study confirms that Tribidrag clones carry abundant genomic variation and that some of it marks individual clonal lineages, which strengthens the case for DNA-based tools to authenticate and track clonal material. At the same time, the weak link between genome-wide differentiation and field performance is a caution against assuming that a genetic profile alone can predict how a clone will behave in a given vineyard. Growers choosing between the consistently productive Zinfandel 1–24 and the smaller-berry, higher-sugar Primitivo selections FPS03 and FPS06 will still need multi-season field data, but they now have a far richer genomic map to guide the search for the mutations that ultimately matter in the glass.

The work also carries a conservation message. Tribidrag survives in Croatia as a heritage cultivar of limited distribution, and the study was supported by the Croatian Science Foundation through the RemainGrape project, which is dedicated to the prospection and genomic analysis of endangered Croatian grapevine cultivars and wild grapevine. By documenting both the phenotypic richness and the genomic depth of variation within a single ancient variety, the research makes the case that preserving old vineyards and clonal collections preserves an irreplaceable archive of somatic evolution. Every century-old vine carries mutations accumulated over generations of vegetative transmission, and each clone is a living record of both natural mutation and human selection. Sequencing eight clones has revealed how much of that record remains to be read, and how much of the connection between the grapevine genome and the wine in the bottle is still waiting to be decoded.

Subject of Research: Whole-genome sequencing and phenotypic analysis of clonal variation in the grapevine cultivar Tribidrag (Zinfandel)

Article Title: Whole-genome sequencing of eight grapevine clones of cv. Tribidrag (Vitis vinifera L.) reveals measurable differentiation not linked directly to phenotypic divergence

Article References: Zdunić, G., Duan, S., Wang, C., Lukšić, K., Marinov, L., Mucalo, A., Ozretić Zoković, M., Maletić, E., Pejić, I., & Chen, W. (2026). Whole-genome sequencing of eight grapevine clones of cv. Tribidrag (Vitis vinifera L.) reveals measurable differentiation not linked directly to phenotypic divergence. BMC Plant Biology. https://doi.org/10.1186/s12870-026-10110-x

Image Credits: AI Generated

DOI: 10.1186/s12870-026-10110-x

Keywords: Tribidrag, Zinfandel, grapevine, clonal variation, whole-genome sequencing, somatic mutation, Vitis vinifera, viticulture, SNP, phenotypic plasticity, plant genetics, clonal selection

Researchers loaded gibberellic acid into biodegradable polymeric nanoparticles and applied the formulation to grapevines in field trials. Compared with conventional applications of the free hormone, the nanoparticle treatment increased grape cluster weight by 104 percent and cluster length by 67 percent. At the level of individual berries, the gains were more modest but still meaningful: berry weight rose by 15 percent, berry length by 4 percent, and berry width by 13 percent. In an industry where cluster size and berry uniformity translate directly into market value, improvements of this magnitude are far from trivial.

The logic behind the approach draws on one of the most active frontiers in agricultural science: controlled-release delivery systems. Nanocarriers, typically built from biodegradable polymers, act as microscopic protective shells that encapsulate active ingredients and release them gradually as the polymer matrix breaks down. This serves two purposes at once. First, it shields sensitive molecules like gibberellic acid from the environmental stressors, principally ultraviolet radiation and elevated temperatures, that would otherwise destroy them. Second, it extends the window of biological activity, so the plant receives a steadier supply of the hormone rather than a single pulse that fades within hours.

As the study’s authors put it, nanocarrier systems ensure more efficient delivery of active substances such as plant growth regulators compared with traditional products. That efficiency matters for reasons that go beyond yield. When a large fraction of an applied agrochemical degrades or drifts before it can act, growers must compensate by applying more, which raises costs and increases the chemical load entering soil and waterways. A delivery system that keeps more of the active ingredient biologically available for longer allows lower doses to achieve the same or better agronomic outcomes, a central goal of sustainable intensification in farming.

Gibberellic acid itself has a storied history in crop science. Identified in the mid-twentieth century as the compound behind the so-called foolish seedling disease of rice, in which infected plants grow abnormally tall, the gibberellin family of hormones was quickly harnessed for agriculture. Today, manufactured gibberellic acid is used worldwide to enlarge grapes, particularly seedless table varieties, to promote malting in barley, to trigger flowering in some crops, and to improve fruit set under unfavorable conditions. In viticulture, its ability to loosen and elongate grape clusters also has a practical side: less densely packed clusters dry faster after rain and are less prone to fungal rot.

What makes the new findings notable is that they were demonstrated under real field conditions rather than in the greenhouse or laboratory, where nano-delivery research often stalls. Translating laboratory formulations into agronomic practice is notoriously difficult. Field environments expose nanoparticles to rain, wind, temperature swings, and microbial communities that can alter their stability and release behavior. Demonstrating that a biodegradable nanocarrier can outperform the conventional formulation in a working vineyard is therefore a significant step toward practical adoption, and it provides a template that could be adapted to other plant growth regulators and crop systems.

The choice of a biodegradable polymer carrier is also significant for the environmental calculus. Unlike some engineered nanomaterials that raise questions about persistence and accumulation in soils, biodegradable polymers are designed to break down into naturally occurring degradation products, limiting long-term residue concerns. This aligns with the broader push in agricultural technology toward materials that perform their function and then disappear. If nano-encapsulation allows growers to use less active ingredient per hectare while achieving larger yield responses, the combined effect could be a genuine reduction in the chemical footprint of high-value horticulture.

The reported effects on berry dimensions and cluster architecture hint at the underlying physiology. Gibberellins promote cell elongation and division, and in grapes this manifests as larger berries and elongated clusters. By maintaining a sustained presence of the hormone at the plant surface and in the vascular system, the nanoparticle formulation appears to have amplified these developmental programs beyond what a single conventional spray can achieve. The study’s authors also report enhancements related to pedicel strength, the structural connection between berry and stem, which influences how well fruit holds on the vine through harvest, an attribute with direct implications for handling and shelf life.

For the grape industry, the implications are immediate and tangible. Table grapes compete in global markets on appearance, size, and uniformity, and growers invest heavily in plant growth regulator programs to meet exacting retail standards. A delivery technology that more than doubles the cluster weight response of the same active ingredient could reshape those programs, reducing both input costs and the number of applications needed through a season. Wine grape production, where cluster compactness and berry size are managed more delicately, could also benefit from the precision that controlled-release systems offer, allowing targeted interventions without the overshoot that conventional sprays sometimes produce.

More broadly, the study adds to a growing body of evidence that nanotechnology, often associated with electronics and medicine, has a serious role to play in feeding a changing world. Encapsulation platforms are being explored for fertilizers that release nutrients on demand, for pesticides that target pests with less collateral exposure, and for the delivery of biologicals such as beneficial microbes and RNA-based crop protection agents. The present work, published with the article title Polymeric Nano-Delivery of Gibberellic Acid Enhances Fruit Quality, Yield, and Pedicel Strength in Grapevine (Vitis vinifera L.), stands out because it pairs a fully biodegradable carrier with a natural plant hormone and validates the combination in the field. As the authors suggest, nanocarrier systems represent a promising and environmentally friendly route to sustainable agricultural production, and if subsequent studies replicate these yield gains across seasons, regions, and crops, the humble nanoparticle may soon become as standard a tool in the orchard and vineyard as the sprayer itself.

Subject of Research: Biodegradable polymeric nanoparticle delivery of gibberellic acid to improve grapevine yield and quality

Article Title: Biodegradable nanoparticle–technology may improve agricultural production

Article References: Biodegradable nanoparticle–technology may improve agricultural production. (n.d.). Original publication

Image Credits: AI Generated

DOI: Not provided

Keywords: gibberellic acid, nanoparticles, biodegradable polymers, grapevine, plant growth regulators, sustainable agriculture, nano-delivery, crop yield, fruit quality, Vitis vinifera, agricultural nanotechnology, Biodegradable

The study was conducted in 2024 at the Tekirdağ Viticulture Research Institute, in a rainfed vineyard whose elevation ranges from roughly 47.45 to 55.46 meters above sea level. The researchers divided the block into three slope positions—lower, middle, and upper—and examined vines grafted onto 5BB rootstock and trained in a bilateral cordon system. Because the vineyard receives no irrigation, every vine depends entirely on rainfall and soil water reserves, making the site a natural laboratory for observing how water availability, which typically declines upslope, translates into physiological and biochemical change.

Across the growing season, the team measured net photosynthesis, stomatal conductance, transpiration, and two measures of water use efficiency on eleven separate occasions, under climatic conditions spanning air temperatures of 30 to 38 degrees Celsius, relative humidity of 26 to 50 percent, and photosynthetically active radiation from 600 to 1800 micromoles per square meter per second. These repeated field measurements captured how the vines responded to genuinely fluctuating Mediterranean summer conditions rather than a single snapshot, giving the dataset unusual ecological realism for a physiological study.

The results revealed a clear stress gradient running up the hill. Vines at the upper slope position showed lower rates of photosynthesis and stomatal conductance than their lower-slope counterparts, but they achieved higher water use efficiency—both in terms of carbon gained per unit of water lost through stomata and per unit transpired. In other words, the upslope vines were running a conservative water-use strategy, keeping their stomata tighter to conserve moisture at the cost of slower carbon assimilation. This is a classic drought-avoidance signature, and its emergence along a purely topographic gradient underscores how strongly slope position governs vine water status even within a single, seemingly uniform vineyard.

Biochemical analyses reinforced the physiological picture. Chlorophyll a, chlorophyll b, and total chlorophyll contents all decreased as one moved upslope, consistent with stress-impaired pigment metabolism, while the ratio of chlorophyll a to b increased—a shift often associated with acclimation to harsher light and water conditions. Meanwhile, the stress-signaling hormone abscisic acid, total phenolics, and tannins all rose with slope position. Abscisic acid is the plant hormone that orchestrates stomatal closure under drought, so its upslope accumulation dovetails neatly with the observed reduction in stomatal conductance and the shift toward water conservation.

Perhaps the most striking results came from high-performance liquid chromatography profiling of individual phenolic compounds. Gallic acid, vanillic acid, syringic acid, caftaric acid, chlorogenic acid, caffeic acid, catechin, epicatechin, rutin, and kaempferol all accumulated more abundantly in vines at the middle and upper slope positions. These compounds are not merely metabolic byproducts; they form a chemically diverse defensive shield, scavenging reactive oxygen species generated when photosynthesis is stressed, reinforcing cell walls, and deterring pathogens. Their upslope enrichment suggests that vines facing tighter water budgets invest more heavily in secondary metabolism, effectively trading growth and carbon gain for chemical resilience.

To test whether these patterns were statistically robust rather than incidental, the researchers applied principal component analysis and hierarchical clustering to the full dataset. Both multivariate approaches cleanly separated the three slope positions, with the upper slope clustering alongside the key stress markers—elevated abscisic acid, phenolics, tannins, and water use efficiency, and depressed chlorophyll and photosynthesis. Bivariate correlation analysis added a further layer: photosynthesis was negatively linked with abscisic acid, intrinsic water use efficiency, and phenolic concentrations, exposing an explicit trade-off between carbon assimilation and defense investment. A vine cannot maximize both at once, and the slope dictates where along that continuum each plant sits.

Proline, a compatible osmolyte that helps cells maintain turgor under water deficit, was also measured, along with antioxidant capacity assessed by the TEAC assay. Together with the hormone and pigment data, these measurements sketch a coherent portrait of ‘Adakarası’ as a cultivar with genuine drought resilience. Rather than collapsing under upslope stress, the vines reprogrammed their physiology and secondary metabolism in an apparently coordinated fashion—closing stomata, signaling with abscisic acid, accumulating osmoprotectants, and ramping up phenolic defenses. Such integrated plasticity is precisely the trait profile that breeders and growers seek as climate zones for quality viticulture shift poleward and upward.

The work also speaks to the concept of terroir, the oft-invoked idea that place imprints itself on wine. While terroir is usually discussed in terms of soil, mesoclimate, and tradition, this study demonstrates that within-vineyard topography alone can generate measurable gradients in leaf chemistry and gas exchange. Slope-driven differences in soil water content, erosion, and solar exposure appear sufficient to push vines into distinct physiological and metabolic states—states that plausibly influence berry composition and, ultimately, wine character. For precision viticulture, the message is that slope position deserves attention not just at the scale of hillsides and valleys, but within individual blocks.

For the Turkish wine industry, the stakes are concrete. ‘Adakarası’ is a heritage variety native to Thrace, and preserving its cultivation under a warming, drying climate depends on understanding where it thrives and why. By identifying the upper slope as a zone of conservative water use and heightened phenolic defense, and the lower slope as one of freer gas exchange, the study offers growers a physiological rationale for vineyard design, rootstock and scion matching, and future irrigation decisions. More broadly, it shows that a humble hillside, read carefully through the language of pigments, hormones, and polyphenols, can teach us how one of humanity’s oldest crops negotiates the stress of a changing world.

Subject of Research: Slope-induced abiotic stress effects on leaf phenolics and physiological activity in the grapevine cultivar Vitis vinifera 'Adakarası'

Article Title: Leaf phenolics, physiological activity and abiotic stress relationship induced by slope in grapevine: Vitis vinifera ‘Adakarası’

Article References: Candar, S., Alço, T., Seçkin, G. U., Şahin, E., Demirağ, O., Güngör, T. A., Bahar, E., & Korkutal, İ. (2026). Leaf phenolics, physiological activity and abiotic stress relationship induced by slope in grapevine: Vitis vinifera ‘Adakarası’. Plant Biosystems, 160(4), Article 217. https://doi.org/10.1007/s44473-026-00228-z

Image Credits: AI Generated

DOI: 10.1007/s44473-026-00228-z

Keywords: grapevine, Vitis vinifera, Adakarası, drought stress, phenolic compounds, abscisic acid, photosynthesis, water use efficiency, chlorophyll, slope gradient, viticulture, climate change

The research team, led by Yuanqian Ni and supervised by Zhaosen Xie and Youmei Li, took advantage of a natural contrast between two grapevine cultivars. ‘Einset Seedless’, abbreviated ENT in the study, tends to produce inflorescences at the lower tendril nodes of its lateral shoots, while ‘Pinot Noir’, or PN, overwhelmingly produces true tendrils at the equivalent positions. By comparing these two varieties node by node, the researchers could ask a precise question: when the same meristem faces the same choice, what is different inside the cells of a plant that flowers versus a plant that climbs?

The homology of tendrils and inflorescences in grapevine is well established. Classical anatomical work showed that both organs arise from the same uncommitted primordia on lateral shoots, and earlier molecular studies found that floral meristem identity genes are expressed even in developing tendrils, as if the tendril were an inflorescence that never quite committed to flowering. Decades ago, pioneering experiments by Srinivasan and Mullins demonstrated that isolated tendrils could even be coaxed into forming inflorescences in vitro, hinting that the switch between the two fates is chemically malleable. What the new study adds is a genome-wide, node-resolved map of the transcriptional landscape in which that switch is thrown.

The team first quantified the anatomical difference, confirming that ENT achieved a markedly higher flowering rate at tendril nodes one through four than PN did. They then harvested tissue from specific tendril nodes in both cultivars and performed RNA sequencing, using an intersection and exclusion strategy to isolate 549 differentially expressed genes that distinguish inflorescence-prone from tendril-prone tissue. When those genes were subjected to Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis, two signaling systems rose to the top: plant hormone signal transduction and mitogen-activated protein kinase cascades. In other words, the decision between flower and tendril appears to be broadcast through the cell by hormonal and phosphorylation-based communication channels rather than by a single master switch.

To move beyond a static snapshot, the researchers applied Mfuzz clustering, a computational method that groups genes according to the shape of their expression trajectories across a developmental series. This revealed that multiple expression programs rise and fall in patterns that track the flowering gradient running along the shoot, from the most inflorescence-prone basal nodes to the tendril-dominated upper nodes. Across every dynamic cluster, plant hormone signal transduction emerged as the predominantly enriched pathway, underscoring that phytohormones are not merely participants in this process but sit at its very center.

Guided by that transcriptional evidence, the team measured the endogenous levels of two key hormones directly in the nodal tissues: zeatin, the classic cytokinin that generally promotes reproductive meristem activity and flowering, and gibberellin GA3, which is more often associated with stem elongation and vegetative growth. The striking result was that the ratio between the two, rather than the absolute level of either hormone alone, paralleled the flowering gradient across nodes and correlated with the gene expression trajectories identified by clustering. A high zeatin-to-GA3 ratio accompanied the inflorescence-prone state, while a lower ratio accompanied tendril formation. This provides concrete physiological support for a cytokinin-gibberellin interaction model in which the balance between these two antagonistic hormones helps determine whether a lateral meristem matures into a flower-bearing branch or an elongating, climbing tendril.

The hormone story dovetails with a long history of viticultural observation. Growth retardants that suppress gibberellin synthesis have been known since the 1960s to influence fruitfulness in grapes, and cytokinin treatments have been shown to convert tendril primordia into inflorescences, with the success of that conversion depending on the genotype. The famous ‘green revolution’ dwarfing mutation in grapevine, which links reduced gibberellin response with enhanced floral induction, fits the same pattern. What the new transcriptomic work contributes is the mechanistic scaffolding: it shows that the endogenous hormone ratio in the organ itself, not just externally applied chemicals, tracks the developmental outcome, and that the downstream transcriptional response is organized into coherent, flowering-correlated trajectories.

Within the pool of differentially expressed transcription factors, one gene stood out. A MADS-box gene named FRUITFULL-LIKE, or VvFUL-L, was markedly upregulated in PN tendrils compared with inflorescence-prone ENT tissue. MADS-box transcription factors are the celebrated architects of floral development, and the FRUITFULL lineage in particular is known from arabidopsis and tomato to regulate meristem identity, flowering time, and inflorescence architecture. To probe what VvFUL-L might be doing, the team overexpressed it heterologously in arabidopsis. The transgenic plants flowered earlier than normal and produced inflorescences with reduced branching, phenotypes consistent with a role in steering lateral meristem development. The authors suggest that VvFUL-L may help tip the uncommitted grapevine lateral meristem toward the tendril program, although confirming that function in grapevine itself will require further work in the crop.

The agronomic implications are immediate and tangible. Excessive tendril growth increases vineyard management costs because tendrils must be removed or redirected by hand or machine, and they can girdle shoots and interfere with canopy machinery. If the cytokinin-to-gibberellin ratio and regulators like VvFUL-L can be manipulated, whether through breeding, targeted gene editing, or growth regulator programs, growers could eventually favor inflorescence formation at the basal nodes where fruit is wanted and suppress the runaway tendril production that wastes the vine’s resources. The study’s authors frame their findings as a foundation for future molecular and breeding studies aimed at managing tendril growth, and the identification of a small set of hormone-responsive genes and a candidate transcriptional regulator is exactly the kind of entry point such efforts require.

There is also a broader evolutionary resonance in the result. Across the grape family, the Vitaceae, tendrils and inflorescences are thought to be variations on a single ancestral organ, and expression studies of APETALA1, FRUITFULL, FLOWERING LOCUS T, and LEAFY orthologs throughout the family support that homology. The Yangzhou study now supplies a quantitative, node-by-node account of how that shared developmental potential is partitioned within a single plant, showing that the fate of each primordium is written in the language of hormone ratios and read out by MADS-box transcription factors. A curling tendril on a Pinot Noir vine, in this light, is not a failed flower but an alternative interpretation of the same instructions, and researchers are learning to read, and perhaps one day to rewrite, the grammar behind that choice.

Subject of Research: Molecular regulation of tendril versus inflorescence development in grapevine lateral shoots

Article Title: Comparative transcriptomics reveals hormone signaling and MADS-box genes in divergent development of inflorescences and tendrils in grapevine lateral shoots

Article References: Ni, Y., Bian, Y., Xie, Z., & Li, Y. (2026). Comparative transcriptomics reveals hormone signaling and MADS-box genes in divergent development of inflorescences and tendrils in grapevine lateral shoots. Plant Cell Reports, 45(9), Article 270. https://doi.org/10.1007/s00299-026-03957-9

Image Credits: AI Generated

DOI: 10.1007/s00299-026-03957-9

Keywords: grapevine, Vitis vinifera, tendrils, inflorescences, cytokinin, gibberellin, MADS-box, VvFUL-L, transcriptomics, hormone signaling, flowering, viticulture

The investigation, published in BMC Complementary Medicine and Therapies, was led by pharmacognosy researcher Amal M. El-Feky, together with Noha E. Ibrahim and Wael Mahmoud Aboulthana, all based at the National Research Centre in Giza. The team collected leaves from a private farm in Wadi El-Natron, in Egypt’s El-Behera Governorate, with the farm owner’s permission and in accordance with local regulations. Rather than sampling a single moment in the growing season, the researchers deliberately built a temporal comparison into the experimental design, reasoning that a grapevine leaf is not a static repository of chemicals but a living tissue whose metabolic output shifts as the plant moves through budbreak, flowering, fruit set, and ripening. That seasonal logic proved correct in striking fashion.

The analytical work began with the most visible layer of leaf chemistry: the photosynthetic pigments. Total chlorophyll peaked in the May harvest, coinciding with the vine’s peak vegetative vigor, while carotenoids—the accessory pigments that help plants dissipate excess light energy—were comparatively higher in the September and March samples. This split is biologically meaningful. Chlorophyll accumulation tracks the leaf’s investment in photosynthetic machinery during active growth, whereas elevated carotenoid levels in the shoulder seasons may reflect protective responses to cooler temperatures and changing light regimes. For anyone hoping to extract pigments or pigment-derived compounds from vine leaves, the data imply that the target molecule should dictate the calendar: chlorophyll seekers should head for the vineyard in late spring, while carotenoid-focused work might do better in early autumn.

Pigments, however, were only the opening act. The heart of the study lay in the secondary metabolites—the phenolic compounds, flavonoids, and tannins that plants synthesize not for photosynthesis but for defense, signaling, and stress tolerance. Using methanolic extracts of the leaves, the researchers quantified total polyphenols, flavonoids, and tannins at each harvest point and found a consistent pattern: the May samples dominated all three categories. This matters because phenolic compounds are the principal drivers of the antioxidant and anti-inflammatory effects attributed to grape leaf extracts in traditional medicine and in modern nutraceutical research. A harvest window that concentrates these molecules effectively multiplies the value of an agricultural stream that would otherwise be discarded.

To move beyond bulk measurements, the team turned to high-performance liquid chromatography, a technique that separates a crude extract into its individual constituents and allows each to be identified and quantified. The HPLC profiles confirmed what the totals had hinted at: the May extract carried a markedly richer load of phenolic and flavonoid constituents than the March or September samples. Among the predominant compounds were chlorogenic acid, rosmarinic acid, gallic acid, and naringenin—a chemically diverse quartet spanning hydroxycinnamic acids, hydroxybenzoic acids, and a flavanone. Each of these molecules has an established research pedigree. Chlorogenic acid is a well-known antioxidant and glucose-modulating agent, rosmarinic acid carries anti-inflammatory credentials, gallic acid is a reference-standard radical scavenger, and naringenin has been studied for effects ranging from lipid metabolism to cytoprotection. The researchers went a step further by isolating the major compounds and structurally identifying them, anchoring the chromatographic assignments in purified material.

With the chemistry mapped, the study pivoted to function. The extracts were subjected to antioxidant and radical-scavenging assays, which measure a sample’s capacity to neutralize reactive oxygen species—unstable molecules that damage lipids, proteins, and DNA and are implicated in aging, inflammation, and chronic disease. Here the May extract again led the field, an outcome that tracks directly with its superior phenolic content, since phenolic hydroxyl groups donate electrons or hydrogen atoms to quench radicals. The correlation between total polyphenol content and antioxidant capacity is one of the most reproducible relationships in natural products research, and this study adds another clean data point to that canon.

The therapeutic screening went considerably further than antioxidant chemistry. In antidiabetic assays, the extracts were tested for their ability to inhibit the carbohydrate-digesting enzymes that determine post-meal glucose spikes, a mechanism shared by several licensed antidiabetic drugs. In anti-Alzheimer’s assays, the focus shifted to enzymes such as acetylcholinesterase, whose inhibition can help preserve the neurotransmitter signaling that degenerates in dementia. Anti-inflammatory and anti-arthritic assays probed the extracts’ capacity to blunt protein denaturation and inflammatory mediators relevant to joint disease, while cytotoxicity testing evaluated the extracts against human cancer cell lines—work conducted under the approval of the Medical Research Ethics Committee of the National Research Centre, under protocol number 04431024. Across this entire panel, the May extract delivered the strongest inhibitory effects, outperforming the March and September samples in every category.

The coherence of the results is what gives the study its force. It is one thing for a single assay to favor one extract; it is another for pigment data, bulk phytochemical quantification, chromatographic profiling, and six distinct bioactivity screens to converge on the same conclusion. That convergence suggests a genuine biological phenomenon rather than a statistical fluke: the vine leaf in May is, in chemical terms, a different object from the same leaf in March or September. The likely drivers are seasonal shifts in the plant’s physiology—peak photosynthetic activity, active growth, and the metabolic demands of flowering and early fruit development—which channel carbon into phenylpropanoid and flavonoid biosynthesis. Environmental variables such as temperature, solar radiation, and water availability in the Wadi El-Natron region during late spring plausibly reinforce this metabolic surge.

The practical implications extend well beyond the laboratory bench. Grape leaves are an abundant, low-cost by-product of viticulture, generated in large volumes during canopy management and harvest worldwide. If processors know that a May harvest—or, more realistically, leaf material collected around the equivalent phenological stage in any given climate—yields extracts with maximal bioactive content, vineyard waste becomes a feedstock for nutraceuticals, cosmeceuticals, and functional food ingredients. The authors frame this explicitly as a valorization opportunity: converting an underused residue into value-added products. The finding also carries a methodological lesson for the wider field of medicinal plant research, where studies routinely report phytochemical data without specifying harvest timing, or compare extracts from batches collected at inconsistent times. If composition can swing this widely within a single growing season, harvest date belongs alongside species, organ, and extraction solvent as a non-negotiable variable in any serious phytochemical study.

Caveats remain, and the authors are careful about scope. All of the bioactivity findings are in vitro—performed in test tubes, enzyme solutions, and cell cultures—so they demonstrate mechanistic potential rather than clinical efficacy. Whether May-harvested grape leaf extracts translate into meaningful antioxidant, antidiabetic, or anti-inflammatory effects in humans will require bioavailability studies, safety profiling, and eventually controlled trials. Dose, formulation, and the identity of the active compounds in vivo all remain open questions. Still, as a piece of applied natural products chemistry, the study lands cleanly: it identifies a specific, actionable harvest window, backs it with layered analytical and bioactivity evidence, and points the way toward turning one of agriculture’s most familiar leftovers into a genuinely useful resource. For the grapevine, it seems, the calendar is not just a farming tool—it is a chemistry lesson.

Subject of Research: Seasonal variation in the phytochemistry and in vitro bioactivities of grapevine (Vitis vinifera) leaves

Article Title: Harvest-Time–Dependent variations in phytochemistry and in vitro bioactivities of Vitis vinifera Leaves

Article References: Harvest-Time–Dependent variations in phytochemistry and in vitro bioactivities of Vitis vinifera Leaves. (n.d.). https://doi.org/10.1186/s12906-026-05578-x

Image Credits: AI Generated

DOI: 10.1186/s12906-026-05578-x

Keywords: Vitis vinifera, grape leaves, polyphenols, flavonoids, harvest time, phytochemistry, antioxidant activity, antidiabetic, anti-inflammatory, cytotoxicity, HPLC, viticulture by-products

The story begins with a systematic census. Scanning the reference genome of the wine grape cultivar Pinot Noir, the researchers cataloged 23 members of the VvCAD family, the genes encoding cinnamyl alcohol dehydrogenase, an enzyme that catalyzes a late, decisive step in lignin biosynthesis by reducing cinnamyl aldehydes into cinnamyl alcohols, the monomeric building blocks that later get stitched into the lignin polymer. Lignin is not merely structural scaffolding; in recent years, plant biologists have increasingly recognized it as an adjustable component of stress responses, with thicker or modified lignin deposits helping plants withstand drought, pathogen attack, and freezing. Among the 23 family members, one gene stood out: VvCAD15-like, a member of the Group II CADs, whose expression was clearly induced when the plants were exposed to cold. That cold-responsive expression pattern made it the prime candidate for functional testing.

To probe what the gene actually does, the team turned to transient expression systems, using Agrobacterium-mediated delivery to temporarily overexpress VvCAD15-like in grape callus tissue and young plantlets. The results were striking and consistent across both systems. Cells and seedlings carrying the extra copies of the gene accumulated more lignin than controls, and their physiological profile shifted in ways that are classic hallmarks of improved stress tolerance. Activities of the three frontline antioxidant enzymes, catalase, peroxidase, and superoxide dismutase, rose, as did levels of proline, a compatible osmolyte that helps cells retain water and stabilize proteins under stress. At the same time, the overexpressing tissues showed reduced malondialdehyde, a breakdown product that signals damage to cell membranes, lower accumulation of hydrogen peroxide, and decreased membrane permeability, indicating that their cellular membranes had suffered less cold-induced injury.

These physiological shifts tell a coherent mechanistic story. Freezing temperatures wreak havoc on plant cells largely through oxidative stress: cold disrupts electron transport in chloroplasts and mitochondria, causing reactive oxygen species such as hydrogen peroxide to accumulate to toxic levels. Those radicals attack membrane lipids, producing malondialdehyde and making membranes leaky, which is why frost-damaged tissue turns water-soaked and collapses. By boosting the antioxidant enzyme arsenal and proline reserves while simultaneously laying down more lignin, VvCAD15-like appears to attack the problem from two directions at once. The lignin reinforces the cell wall itself, providing a physical barrier that helps the cell maintain its shape and integrity as ice crystals form and expand outside the membrane, while the enhanced antioxidant capacity mops up the radicals that would otherwise corrode the cell from within.

Perhaps the most intriguing finding, however, lies deeper in the regulatory hierarchy. When the researchers examined the expression of cold-signaling genes in the overexpressing tissues, they found that VvCAD15-like upregulated VvCBF1 and VvCBF3, along with VvICE1a. The CBF pathway is the canonical cold-response cascade in plants: ICE1 transcription factors activate CBF genes, and the CBF proteins in turn switch on a large battery of genes that prepare the plant for freezing, a process known as cold acclimation. That a lignin-biosynthesis gene would feed into this pathway was unexpected. It suggests VvCAD15-like is not simply a downstream bricklayer adding wall material, but a participant in the signaling conversation that tells the whole plant winter is coming, amplifying the acclimation program rather than merely executing one of its outputs.

Transcriptome sequencing reinforced this picture of a gene with far-reaching influence. The global expression data pointed to potential connections between VvCAD15-like and the phenylpropanoid pathway, the metabolic highway that supplies lignin precursors, as well as flavonoid biosynthesis and hormone signaling, all of which are implicated in cold responses. Flavonoids can act as antioxidants and cryoprotectants, and hormones such as abscisic acid and jasmonates are well-established modulators of stress tolerance. While the transcriptomic evidence is correlative, it sketches a network in which a single CAD gene could coordinate wall reinforcement, secondary metabolism, and hormonal tuning, a level of integration that would explain the breadth of physiological changes observed in the overexpression experiments.

The team then asked the reverse question: what switches VvCAD15-like on when temperatures drop? Using yeast one-hybrid screening and dual-luciferase reporter assays, two complementary techniques for detecting transcription factors that bind and activate a target promoter, they identified three regulators capable of binding the VvCAD15-like promoter under cold treatment: VvbHLH112, VvbHLH95, and VvNF-YA7. The bHLH family is of particular interest here because ICE1, the famous upstream activator of the CBF cascade, is itself a bHLH transcription factor. Among the three candidates, VvbHLH112 showed transcriptional activation activity in its own right, and VvbHLH95 is closely related to AtICE1 from Arabidopsis, hinting that the cold induction of VvCAD15-like may be wired into the same regulatory machinery that governs the broader cold acclimation response.

This regulatory architecture suggests a possible feed-forward loop: cold activates bHLH factors, which turn on both the CBF pathway and VvCAD15-like, and VvCAD15-like in turn further boosts VvCBF1/3 expression while thickening the wall. If confirmed, such a loop would explain how a relatively modest change in one wall-building enzyme could produce a coordinated, whole-cell shift toward freezing readiness. It also places VvCAD15-like in a growing family of case studies. Recent work in pepper identified a CAD1 module that increases lignin accumulation and cold resistance, and studies in banana and poplar have similarly linked cell-wall remodeling enzymes to abiotic stress performance, indicating that the non-canonical stress roles of lignin-pathway genes are emerging as a general theme across the plant kingdom.

The authors are careful to flag the limits of their system. All of the functional evidence came from transient expression in calli and plantlets, not from stable transgenic vines, so the conclusions, while strongly supported at the cellular level, still await confirmation in whole plants carrying the gene permanently through their lifecycle. Transient assays are fast and powerful for screening gene function in grapevine, a species notorious for slow and laborious stable transformation, but they cannot capture developmental effects, long-term fitness consequences, or possible trade-offs, such as whether extra lignin deposition might compromise growth, fruit quality, or wood flexibility. Stable overexpression lines and, ideally, knockout or knockdown lines will be needed to establish whether VvCAD15-like is genuinely sufficient and necessary for cold tolerance in the field.

Even with those caveats, the practical implications are considerable. Grapevine is one of the world’s most economically important fruit crops, and cold is a defining constraint on where vineyards can thrive; late spring frosts alone cause recurring, multimillion-dollar losses. A validated cold-tolerance gene with a known regulatory network would give breeders a molecular target, whether through marker-assisted selection for favorable alleles, genome editing to tune expression, or transgenic approaches in rootstocks. The study also adds a conceptual twist to plant stress biology: it demonstrates that a canonical cell-wall biosynthesis gene can double as a signaling node in the CBF cold-response pathway, blurring the line between structural and regulatory defenses. As climate volatility brings sharper frosts to traditional and emerging wine regions alike, understanding and harnessing genes like VvCAD15-like may prove essential to keeping vines, and the industries built on them, productive in a colder-than-comfortable world.

Subject of Research: The role of the grape lignin biosynthesis gene VvCAD15-like in enhancing cold tolerance in Vitis vinifera

Article Title: Functional characterization of the grape VvCAD15-like gene in enhancing cold tolerance via regulation of lignin biosynthesis

Article References: Sun, X., Wang, H., Zeng, F., Wang, N., Zeng, B., Zhao, J., Gao, J., Lu, S., Liang, G., Mao, J., & Chen, B. (2026). Functional characterization of the grape VvCAD15-like gene in enhancing cold tolerance via regulation of lignin biosynthesis. Plant Cell Reports, 45(10), Article 316. https://doi.org/10.1007/s00299-026-03977-5

Image Credits: AI Generated

DOI: 10.1007/s00299-026-03977-5

Keywords: grapevine, VvCAD15-like, cold tolerance, lignin biosynthesis, cinnamyl alcohol dehydrogenase, CBF pathway, VvCBF1, VvICE1a, reactive oxygen species, cell wall reinforcement, transcription factors, Vitis vinifera

The study, published in the American Journal of Enology and Viticulture, found that consumers showed no consistent bias against the color of wines made from hybrid grape varieties. When evaluated alongside pinot noirs from Burgundy, Oregon and the Finger Lakes, several hybrid wines ranked among the most visually appealing in the entire panel. More striking still, color, regardless of variety, turned out to be a weak predictor of whether drinkers actually enjoyed what was in the glass. The statistical relationship between how much panelists liked a wine’s appearance and how much they liked it after tasting explained only about eight percent of the variation in their responses, leaving taste and aroma to dominate the verdict.

For Anna Katharine Mansfield, associate professor of enology at Cornell AgriTech and lead author of the work, the question had been nagging at her for years. Prior to coming to Cornell, she worked with breeders at the University of Minnesota, where there was a persistent assumption that consumers would reject a wine if its color did not look sufficiently Vitis vinifera-like. Yet, as she notes, no one had ever actually studied that question directly. The research was also motivated by wine chemistry, according to co-author Catherine Dadmun, a food science doctoral student. In Europe, historic restrictions govern certain chemical color compounds that appear uniquely in hybrid grapes, and that regulatory history has fed an assumption that the compounds must produce low-quality color. The team set out to clarify what is and is not important for consumer perception of color quality from a chemical composition standpoint.

The stakes extend well beyond academic curiosity. As winemaking regions across North America and Europe grapple with more erratic weather, late frosts and increasing fungal disease pressure, hybrid cultivars offer a compelling alternative to the European grapes that have dominated fine wine for centuries. Varieties such as marquette, Maréchal Foch and St. Croix can be grown with far fewer pesticide applications and can survive winters that would devastate conventional vineyards. For growers confronting shorter windows for spraying, shifting pest pressures and unseasonable cold, that resilience is not a niche advantage but an increasingly central part of vineyard economics. Commercial adoption, however, has been slowed by persistent doubts about whether consumers will accept the resulting wines, doubts that often center on appearance rather than flavor.

To test one of those doubts directly, the research team recruited 82 regular red wine drinkers through the Cornell Sensory Evaluation Center. Panelists were asked to evaluate eight commercial red wines: five made from hybrid cultivars sourced from New York, Wisconsin, Tennessee and Iowa, plus pinot noirs from three regions, all presented without any indication of which was which. The design separated three distinct judgments. First, panelists rated how much they liked each wine’s appearance. Second, they rated how much they expected to enjoy the wine based on color alone. Finally, after tasting, they rated how much they actually liked it. This structure allowed the researchers to disentangle the visual halo effect, in which appearance shapes expectation, from the lived experience of aroma, texture and flavor on the palate.

The results cut in two directions at once. Color did matter, but mostly as a prelude. Wines that appeared lighter or showed more yellow and brown tones scored lower for visual appeal and generated weaker expectations before tasting. Three wines clustered at the bottom of the visual rankings: a Finger Lakes pinot noir, a Norton from Tennessee and a corot noir from near Albany, New York. Notably, that bottom tier was not exclusively hybrid; a pinot noir from a prestigious viticultural region sat alongside the two hybrids, suggesting that pale or brown-tinged color is a general vulnerability rather than a hybrid-specific flaw. The critical finding came when panelists tasted all eight wines: color’s predictive power largely evaporated, and the wines that looked least promising did not consistently taste worst.

The chemistry behind wine color helps explain why the industry’s assumptions deserve scrutiny. Red wine color derives primarily from anthocyanins, the pigments extracted from grape skins during fermentation, and hybrid grapes carry distinctive anthocyanin profiles that differ from those of pure Vitis vinifera varieties. European regulators historically restricted certain of these compounds, and that regulatory posture hardened into a market prejudice: if the compounds are treated differently, the reasoning went, the color they produce must be inferior. The Cornell data challenge that chain of logic. When the researchers evaluated hue-liking and overall appearance-liking, Dadmun observed, the pinot noirs and hybrid grapes were largely in the same pool, meaning that consumers responded to the visual qualities of the wines themselves rather than to any detectable hybrid signature.

The finding holds an implicit challenge to long-standing wine industry assumptions. Darker wines have been associated with higher quality for so long that the bias has shaped marketing, criticism and even breeding priorities, making some winemakers reluctant to promote hybrids at all. But the Cornell data showed no meaningful correlation between color intensity and actual liking. What seemed to drive the lower visual scores for the three least-liked wines was not lightness per se, but a tendency toward brownish, yellow-tinged hues rather than the deep red-purple that consumers associate with a young, well-made red. In other words, drinkers are not reading depth of color as a quality signal so much as reading hue as a freshness signal, and a wine that leans brick or amber risks reading as old or oxidized regardless of what is actually in the bottle.

Mansfield also points to a practical wrinkle in how color judgments are made in the real world: evaluations typically happen in the glass, not the bottle. Because green glass is more protective against light damage, wine is rarely sold in clear bottles, which means most consumers never see the color until the wine is already poured. By that point, the purchase decision has been made, and the sensory experience of tasting is about to overtake any visual impression. Color, she suggests, is a non-issue in some ways, and her hope is that people breeding hybrids can simply worry less about it. That message lands at a pivotal moment, as breeders across cold-climate regions continue releasing new cultivars designed for sustainability as much as for style.

For an industry navigating climate disruption, the implications are considerable. If consumer acceptance of hybrid wines hinges far more on flavor than on hue, then growers and producers can invest in viticultural and enological quality, aroma development and site expression rather than chasing pigment targets bred from Vitis vinifera expectations. The study, conducted as an observational sensory trial with regular red wine drinkers rather than trained experts, offers a consumer-grounded counterweight to decades of anecdote. It suggests that the visual gatekeeping that has kept hybrid wines out of premium conversations rests on a shaky empirical foundation, and that the palette, in the end, matters far less than the palate.

Subject of Research: Consumer perception of red wine color and quality in interspecific hybrid grape varieties

Article Title: Hue cares? Cornell study says wine color isn't the whole picture

Article References: Hue cares? Cornell study says wine color isn't the whole picture. (n.d.). Original publication

Image Credits: AI Generated

DOI: Not provided

Keywords: wine color, hybrid grapes, Vitis vinifera, enology, anthocyanins, sensory evaluation, consumer perception, climate change, pinot noir, Cornell University, viticulture, American Journal of Enology and Viticulture

The research team used an in ovo experimental approach, meaning the work was carried out inside fertilized eggs rather than in living mammals. This model, widely used in developmental biology and nutrition research, allows scientists to observe how bioactive compounds influence embryonic growth in a controlled, ethically streamlined system. To provoke intestinal stress, the researchers applied dextran sulfate sodium, or DSS, a chemical well known for its ability to damage the intestinal lining and trigger inflammation. DSS is a standard tool in inflammatory bowel disease research, and its effects on mature gut tissue are extensively documented. Applying it in an embryonic context offered the team a way to test whether a natural phenolic extract could counteract inflammatory injury before birth.

Phenolic compounds are a broad family of plant secondary metabolites that include flavonoids, phenolic acids, tannins, and stilbenes such as resveratrol. Grape skins are particularly dense in these molecules because they serve as the fruit’s first line of chemical defense against ultraviolet radiation, pathogens, and mechanical injury. White grape varieties, though often assumed to be phenolically inferior to their red counterparts, still contain substantial quantities of these compounds, concentrated primarily in the skin. Because winemaking presses the juice away from the skins, the pomace left behind after processing represents an abundant and inexpensive reservoir of bioactive material that the food industry has increasingly sought to valorize.

In the study, the researchers extracted phenolics from white grape skins and administered the extract to developing embryos subjected to DSS-induced stress. The team then evaluated a battery of indicators reflecting intestinal health, including markers of oxidative stress, inflammatory signaling, and structural integrity of the gut tissue. The results indicated that embryos receiving the grape skin extract showed a dampening of the harmful responses triggered by DSS. In practical terms, the phenolic treatment appeared to buffer the developing intestine against the chemical insult, preserving tissue condition and moderating the biochemical cascade that DSS normally sets in motion.

The mechanism behind this protection likely rests on the dual antioxidant and anti-inflammatory capacities of grape phenolics. Oxidative stress arises when reactive oxygen species overwhelm the cell’s antioxidant defenses, damaging lipids, proteins, and DNA. DSS exposure accelerates this imbalance in intestinal tissue, while simultaneously activating inflammatory pathways that recruit immune signaling molecules and further degrade the epithelial barrier. Phenolic compounds interrupt this cycle at multiple points: they scavenge free radicals directly, chelate pro-oxidant metal ions, and modulate intracellular signaling pathways such as nuclear factor kappa B, a master regulator of inflammatory gene expression. By intervening on both fronts, the extract can reduce the amplification loop in which tissue damage and inflammation feed each other.

What makes the in ovo model particularly compelling is the developmental window it captures. The embryonic intestine undergoes rapid morphogenesis, with epithelial cells proliferating, differentiating, and organizing into the villi and crypts that will later absorb nutrients. Inflammatory stress during this period can have lasting consequences for gut function, immune programming, and even systemic health after hatching or birth. Demonstrating that a plant-derived extract can protect this vulnerable phase suggests that maternal or early-life nutritional interventions with polyphenol-rich foods might one day support gastrointestinal resilience from the very beginning of life. The researchers emphasize, however, that the study establishes a proof of concept in an experimental model rather than a direct clinical recommendation.

The work also carries significant implications for the food and agricultural industries. Grape pomace is generated in enormous quantities worldwide, and while some of it is repurposed for animal feed or compost, much of it is discarded, creating both an economic loss and an environmental burden. If phenolic extracts from white grape skins can be standardized and shown to deliver consistent bioactivity, they could become ingredients in functional foods, dietary supplements, or feed additives aimed at supporting gut health. The in ovo platform itself offers the industry a relatively fast and inexpensive screening tool for evaluating such ingredients before committing to more costly animal or human trials.

Critical questions remain before any such translation can occur. The dose, timing, and bioavailability of grape skin phenolics in a developing organism are not yet fully resolved, and the specific compounds responsible for the protective effect have not been isolated from the complex mixture. Phenolic extracts are chemically heterogeneous, and their activity can depend on synergies among dozens of molecules. Moreover, absorption and metabolism of polyphenols differ substantially between an embryonic environment and a mature digestive system, so the effective dose in humans or livestock could differ considerably from what works in ovo. Follow-up studies will need to identify the active fractions, characterize dose-response relationships, and confirm safety across developmental stages.

Nevertheless, the study strengthens a broader scientific narrative: that the boundary between nutrition and medicine is increasingly porous, and that compounds once dismissed as mere plant pigments can act as genuine modulators of physiology. The intestine is not simply a digestive tube but a dynamic interface between the organism and its environment, housing the majority of the body’s immune cells and communicating constantly with the nervous system and the microbiome. Protecting this organ during development may therefore ripple outward into lifelong health outcomes, a hypothesis that research on early nutrition continues to support.

For now, the image of a winemaking waste product shielding an embryonic gut from inflammatory injury is a striking illustration of how food science, developmental biology, and sustainability can converge. The study, published in npj Science of Food, demonstrates that nature’s chemical arsenal, even in varieties of grape long overshadowed by their red-skinned cousins, contains molecules capable of defending the most delicate stages of life. As researchers refine the extraction methods, identify the active compounds, and test the findings in more complex models, white grape skins may find a second life not in the glass but in the clinic, the nursery, and the feed mill.

Subject of Research: Effects of white grape skin phenolic extract on DSS-induced embryonic intestinal stress in an in ovo model

Article Title: White grape (Vitis vinifera) skin phenolic extract impacts DSS-induced embryonic intestinal stress (in ovo)

Article References: Huang, M. Y., & Tako, E. (2026). White grape (Vitis vinifera) skin phenolic extract impacts DSS-induced embryonic intestinal stress (in ovo). npj Science of Food. https://doi.org/10.1038/s41538-026-01130-w

Image Credits: AI Generated

DOI: 10.1038/s41538-026-01130-w

Keywords: grape skin phenolics, Vitis vinifera, DSS, in ovo, intestinal stress, antioxidants, anti-inflammatory, embryonic development, gut health, polyphenols, food byproducts, White

The team began by charting where and when VvbHLH10 switches on. Under laboratory conditions, its transcription was rapidly and strongly induced by both salt and alkali treatments, a pattern consistent with a gene recruited into the front line of the stress response. Intriguingly, the gene is also predominantly expressed in actively growing tissues, including latent buds, young stems and young tendrils, placing it at the intersection of stress defense and development. Using a VvbHLH10-GFP fusion protein, the researchers confirmed that the protein localizes to the nucleus, the expected working address for a transcription factor that binds promoter regions and orchestrates the expression of downstream target genes.

To test function rather than mere correlation, the researchers deployed two complementary experimental systems. The first was homologous overexpression in grape callus cultures, an in vitro system derived from the plant itself. When grape calli engineered to overexpress VvbHLH10 were challenged with salt and alkali stress, they survived and grew significantly better than control calli. Biochemical assays pointed to the mechanism behind that resilience: the engineered tissues accumulated markedly lower levels of reactive oxygen species (ROS) and malondialdehyde (MDA), two classic signatures of oxidative damage. Because salt and alkali stress disrupt photosynthesis and electron transport, plants typically respond with bursts of ROS that damage membranes, proteins and DNA; reducing that oxidative burden is a central goal of stress-resilience breeding.

The second system took the gene out of grapes altogether. In a heterologous expression approach, the team introduced VvbHLH10 into tomato, a widely used surrogate that allows plant scientists to ask whether a gene’s function is conserved across species. The answer was a clear yes. Transgenic tomato lines overexpressing VvbHLH10 showed markedly improved tolerance to salt-alkali treatment compared with wild-type controls, again with reduced oxidative damage and better overall growth. Cross-species validation of this kind matters for breeders because it suggests the underlying regulatory module is not a grape-specific quirk but a portable stress-protection circuit that could, in principle, be engineered into other horticultural crops facing the same soil chemistry problems.

Then came the surprise. Beyond its protective function, ectopic expression of VvbHLH10 in tomato promoted axillary bud outgrowth and altered the plants’ vegetative architecture. Axillary buds are the embryonic shoots that sit in the angle between leaf and stem, and whether they remain dormant or break out into branches is governed by a tight hormonal and transcriptional network involving strigolactones, auxin and cytokinin. A transcription factor that simultaneously modulates this developmental switch and the stress response is unusual, and it hints that VvbHLH10 belongs to a growing group of bHLH proteins whose roles have diversified beyond single functions. In practical terms, the same gene that helps a vine survive degraded soil could also be tuned to change how the plant allocates its growth, a lever for shaping canopy structure and productivity.

The dual identity of VvbHLH10 fits into a broader emerging picture of the bHLH family. With hundreds of members in most plant genomes, bHLH transcription factors have been implicated in everyone’s favorite processes, from iron uptake and flavonoid biosynthesis to light signaling and hormone crosstalk. Group 9 bHLH factors, the subclass to which VvbHLH10 belongs, have drawn particular interest for their roles in abiotic stress responses. What this study adds is evidence that in a woody perennial crop of global economic importance, one group 9 member can be rapidly mobilized by salinity and alkalinity cues, act in the nucleus to dampen oxidative injury, and at the same time remodel shoot architecture by freeing axillary buds from dormancy.

For viticulture, the implications are concrete. Salt-alkali soils are expanding in many grape-growing regions as irrigation, climate change and intensive cultivation push pH and sodium levels upward, and vineyards on marginal land often suffer stunted vines, poor bud break and yield losses. A gene that improves survival under both saline and alkaline conditions, verified in both homologous and heterologous systems, offers a candidate target for marker-assisted selection or genome editing. Because VvbHLH10 is naturally expressed in latent buds, breeders could also exploit its developmental role to improve bud fertility and branching in varieties where shy bud break limits yield. The authors position VvbHLH10 as a promising candidate for the genetic improvement of both salt-alkali tolerance and plant architecture in grapevine.

The research, led by Rui Xu and Huiping Liu as co-first authors and corresponding author Ke Li, was published open access on 12 September 2026 after acceptance on 9 September, and was supported by the Key Research and Development Project of Shandong Province, the National Natural Science Foundation of China, the Shandong Provincial Natural Science Foundation and several programs at the Shandong Academy of Agricultural Sciences. The team also released transcriptomic datasets from VvbHLH10-overexpressing tomato as supplementary material, giving the community a resource to trace which downstream pathways the transcription factor rewires, from antioxidant defenses to branching hormones.

What remains to be resolved is the direct target repertoire of VvbHLH10 and how its stress-protective and developmental outputs are mechanistically linked. If the same set of bound promoters underlies both ROS quenching and bud release, that would suggest an elegant coupling in which growth resumption under stress is actively licensed rather than merely permitted. If the two functions run through separate downstream circuits, breeders may be able to dial in salt tolerance without unwanted changes in vine shape. Either outcome broadens understanding of the functional diversification of bHLH transcription factors in horticultural crops and brings grape growers one gene closer to vines that thrive where the soil fights back.

Subject of Research: Functional characterization of the VvbHLH10 transcription factor in grapevine salt-alkali stress tolerance and axillary bud growth regulation

Article Title: VvbHLH10 promotes axillary bud growth and salt-alkali tolerance in grapevine

Article References: Xu, R., Liu, H., Mu, Q., Li, A., Wang, F., & Li, K. (2026). VvbHLH10 promotes axillary bud growth and salt-alkali tolerance in grapevine. BMC Plant Biology. https://doi.org/10.1186/s12870-026-09949-x

Image Credits: AI Generated

DOI: 10.1186/s12870-026-09949-x

Keywords: grapevine, VvbHLH10, bHLH transcription factor, salt-alkali stress, axillary bud growth, reactive oxygen species, abiotic stress tolerance, Vitis vinifera, plant architecture, viticulture, plant molecular biology, transgenic plants