Labrusca Research Articles

Mites associated with Vitis labrusca (Vitaceae) in southern Brazil: Population dynamics and ecology

Viticulture is one of the main economic activities in Rio Grande do Sul (RS), Brazil, with emphasis on the American grape varieties, Vitis labrusca L. (Vitaceae), used in producing juices and wines. The present work aimed to identify the mite species associated with American grapevines (V. labrusca), their possible natural enemies, and their population fluctuations. The selected varieties were: Bordô (Bd) and Couderc (Cc and Cd) in Dois Lajeados (RS), Bordô (Bi) in Imigrante (RS) and Bordô (Bp), in Putinga (RS). The study was conducted monthly between March 2017 and March 2018, evaluating 20 randomly selected plants from each municipality. We found 5,452 mites belonging to 13 families, distributed across 29 genera and 42 species, or belonging to the suborder Oribatida. Higher mite richness was observed on Cc (12 species) and higher abundance on Cd (2,812 specimens), Cc (868) and Bi (799). Among the predatory mite families, Stigmaeidae had the highest abundance (896 specimens), followed by Phytoseiidae (746). The most abundant species observed were Euseius mesembrinus (Dean), Agistemus riograndensis Johann & Ferla, Tydeus californicus (Banks), Polyphagotars-onemus latus (Banks) and Tarsonemus sp. This is the first study in southern Brazil that evaluates and reports the mite fauna and its ecology on American grape varieties, with high abundance and frequency of predatory mites. This work is important to assist in implementing management techniques that promote the maintenance of predatory mite species in these vineyards.

Damage on grapevine cv. Niagara Rosada leaves caused by the combined effect of temperature and Asian grapevine leaf rust (Neophysopella tropicalis)

AbstractAsian grapevine leaf rust (AGLR), caused by Neophysopella tropicalis, is a problem for viticulture, especially in latitudes lower than 25° S, which include the most significant production regions in Brazil. Climate change has raised new concerns in agriculture as temperature can affect the resistance of plants to pathogens. With the aim of understanding how air temperature rise affects the AGLR pathosystem, measurements of leaf gas exchange and epidemiological and histopathological analyses were carried out on control and inoculated leaves of Vitis labrusca ‘Niagara Rosada’ grown at 25°C and 30°C. The lesion density and rust severity were higher at 25°C than 30°C, and the ratio between adaxial surface necrosis and the abaxial surface area occupied by pustules was >1 only at 30°C, presenting a necrosis not associated to the pathogen lesion. In fact, leaf necrosis was identified on control plants kept at 30°C and associated with gerontoplasts, representing accelerated leaf senescence. The AGLR pathogen reduced gas exchange and photosystem II activities at 25°C, with no difference between control and inoculated plants at 30°C. Our results indicate that AGLR is sensitive to increasing air temperature. However, the accelerated leaf senescence caused by the combination of N. tropicalis infection and temperature on Niagara Rosada can lead to high leaf damage.

Determination of Rooting and Vine Sapling Rates of Single-Bud Cuttings Prepared from Vitis labrusca L. Grape Cultivars

Determination of Rooting and Vine Sapling Rates of Single-Bud Cuttings Prepared from Vitis labrusca L. Grape Cultivars

Antioxidant capacity and cytotoxic effect of an optimized extract of isabella grape (Vitis labrusca) on breast cancer cells

The phenolic profile of Isabella grape (Vitis labrusca) offers beneficial properties to human health and makes it a functional food product. In order to better understand the phenolic compounds found in this grape variety and the biological effect they induce on breast cancer cells, an ultrasound-assisted extraction was carried out. During the extraction of polyphenols from Isabella grapes organically grown in Antioquia (Colombia), parameters such as frequency (33 kHz and 40 kHz), time and solvent were optimized to finally obtain a crude extract with antioxidant properties (Oxygen Radical Absorbance Capacity, ORAC: 293.22 ± 34.73 μmol of Trolox/g of sample), associated with a total polyphenol content (TPC) of 43.14 ± 5.00 mg GAE/g sample and a total anthocyanin content composed of 17.69 ± 2.59 mg of malvidin-3-glucoside/100 g of sample. MCF-7 breast cancer cells were treated with different concentrations of the optimized extract, and results show a decrease in cell viability related to mitochondrial membrane depolarization, ROS increase, and chromatin condensation. To determine the possible death induction mechanism, molecular docking was simulated to predict the molecular interactions between the most abundant phenolic compounds in Isabella grape and the main apoptosis-related proteins. The results obtained from in silico and in vitro experiments were consistent with each other, suggesting that the phenolic compounds found in Isabella grape can be considered potential adjuvant chemopreventive agents for the treatment of breast cancer.

Potential role of exogenous melatonin involved in postharvest quality maintenance of Vitis labrusca × vinifera 'Kyoho'.

Melatonin is an endogenous free radical scavenger with antioxidant activity that preserves the commercial value of postharvest fruits and delays fruit senescence. To explore the effect of exogenous melatonin on antioxidants and aroma volatile compounds of grapes (Vitis labrusca × vinifera 'Kyoho'), the grapes were treated with distilled water (control), 50 μmol L-1 of melatonin (M50), and 100 μmol L-1 of melatonin (M100) for 30 min and were then stored at 4 °C for 25 days. Exogenous melatonin decreased the rachis browning index, the decay development, the weight loss rate, the berry abscission rate, and the respiration rate, promoted the accumulation of total phenolics and total flavonoids, and delayed the reduction of anthocyanins and total soluble solids. In volatile compounds, the accumulation of esters, aldehydes, and alcohols in grapes was promoted, and the terpenes content was reduced by exogenous melatonin. Exogenous melatonin had potentially positive effects on the postharvest life and quality maintenance of grapes. These findings provide theoretical support for the application of melatonin in grape storage and preservation. © 2023 Society of Chemical Industry.

Fungitoxic role of endogenous eugenol in the hybrid grapevine cultivar Baco blanc resistant to <i>Botrytis cinerea</i>

Eugenol (2-methoxy-4-(2-propenyl)-phenol), widely spread in various plants, notably clove, basil and bay, is a well-known antifungal and antibiotic molecule that is abundant in the hybrid grapevine cultivar Baco blanc (Vitis vinifera × Vitis riparia × Vitis labrusca). This variety, created by François Baco (19th century), is confirmed in this study as highly resistant to Botrytis cinerea by comparing fruit rot incidence and severity with two Vitis vinifera cultivars: Folle Blanche and Ugni Blanc. According to two major antibiosis modes of action, i.e., direct or volatile, this study demonstrated the efficiency of eugenol in vitro by also investigating precisely the effect on B. cinerea of small concentrations of eugenol, 3 to 4 ppm, corresponding to IC10. Moreover, the vapour-inhibiting effect was shown to be highly powerful. The total eugenol concentration peaked at the veraison stage, exceeding 1000 μg×kg-1 in the skin of Baco blanc berry under our conditions. At this point, leaf removal in the bunch zone induced a significant increase in eugenol (32 %), from 1118 to 1478 μg×kg-1, which was also associated with a significant decrease in B. cinerea infection in the vineyard. Thus, for the first time, eugenol, as an endogenous molecule of Baco blanc, was clearly demonstrated to be an inducible compound in the vineyard. Furthermore, significant intravarietal variability in eugenol concentrations according to the Baco blanc clone was demonstrated to be associated with significant differences in fruit susceptibility to the plant pathogen assessed in biotests. Interestingly, in keeping with fruit ontogenic resistance, a significant negative correlation was established between the technological maturity of berries and the total eugenol content in the berry skin. Finally, the time-progress study of the two biochemical forms of eugenol (bound vs. free eugenol) allowed us to hypothesise the effectiveness against the plant pathogen of some precursor forms of eugenol, and the corresponding biochemical structures are currently being investigated. Thus, eugenol appears to be a key biochemical marker of ontogenic resistance in the hybrid cultivar Baco blanc.

Comparison of Phenolic Profile and Antioxidant Properties of Pulp and Seeds of Two Different Grapes Types (Vitis vinifera L. and Vitis labrusca L.) Grown in Anatolia

Comparison of Phenolic Profile and Antioxidant Properties of Pulp and Seeds of Two Different Grapes Types (Vitis vinifera L. and Vitis labrusca L.) Grown in Anatolia

Biosorption of bioactive compounds in bacterial nanocellulose: Mechanisms and physical-chemical properties

Bacterial cellulose (BC) is a biomaterial produced by Gluconacetobacter xylinus, with wide applicability in different areas, such as biomedical, pharmaceutical, and food. BC production is usually carried out in a medium containing phenolic compounds (PC), such as teas, however, the purification process leads to the loss of such bioactive. Thus, the innovation of this research consists of the reincorporation of PC after the purification of the BC matrices through the biosorption process. In this context, the effects of the biosorption process in BC were evaluated to maximize the incorporation of phenolic compounds from a ternary mixture of hibiscus (Hibiscus sabdariffa), white tea (Camellia sinensis), and grape pomace (Vitis labrusca). The biosorbed membrane (BC-Bio) showed a great concentration of total phenolic compounds (TPC = 64.89 mg L−1) and high antioxidant capacity through different assays (FRAP: 130.7 mg L−1, DPPH: 83.4 mg L−1, ABTS: 158.6 mg L−1, TBARS: 234.2 mg L−1). The physical tests also indicated that the biosorbed membrane presented high water absorption capacity, thermal stability, low permeability to water vapor and improved mechanical properties compared to BC-control. These results indicated that the biosorption of phenolic compounds in BC efficiently increases bioactive content and improves physical membrane characteristics. Also, PC release in a buffered solution suggests that BC-Bio can be used as a polyphenol delivery system. Therefore, BC-Bio is a polymer with wide application in different industrial segments.

Life history traits of spotted lanternfly (Hemiptera: Fulgoridae) when feeding on grapevines and tree of heaven.

The invasive planthopper, spotted lanternfly (SLF), Lycorma delicatula (White) (Hemiptera: Fulgoridae), feeds on a broad range of plants including species of economic importance such as grape. Although SLF feeds on wild and cultivated grape, the effect of grapevines on the insect's life history traits is unknown. This study examined the effect of cultivated Concord grapevines (Vitis labrusca) and the insect's preferred host tree of heaven (TOH), Ailanthus altissima, on SLF development, survival, reproduction, and body mass. Newly emerged nymphs were allowed to feed on either TOH, Concord grapevines or a mixed diet of Concord grapevines plus TOH through adulthood until death. Development, mortality, and oviposition of paired adults were tracked daily to calculate the SLF rate of development, survival, and reproduction among treatments. When feeding exclusively on Concord grapevines, SLF was able to develop and reproduce but had higher mortality, slower development, and produced fewer eggs. SLF fed on the mixed diet of grapevines plus TOH exhibited faster nymphal development, laid more eggs, and had higher body mass compared with those fed only on grape or TOH. SLF had greater survival when fed on either the mixed diet or on TOH alone. We conclude that Concord grapevines are a poor-quality host for SLF, but when combined with TOH, SLF fitness increases above that of feeding on TOH alone. This study supports the elimination of TOH as a part of SLF vineyard management practices.

Candidate gene discovery of Botrytis cinerea resistance in grapevine based on QTL mapping and RNA-seq.

Grape gray mold disease (Botrytis cinerea) is widespread during grape production especially in Vitis vinifera and causes enormous losses to the grape industry. In nature, the grapevine cultivar 'Beta ' (Vitis riparia × Vitis labrusca) showed high resistance to grape gray mold. Until now, the candidate genes and their mechanism of gray mold resistance were poorly understood. In this study, we firstly conducted quantitative trait locus (QTL) mapping for grape gray mold resistance based on two hybrid offspring populations that showed wide separation in gray mold resistance. Notably, two stable QTL related to gray mold resistance were detected and located on linkage groups LG2 and LG7. The phenotypic variance ranged from 6.86% to 13.70% on LG2 and 4.40% to 11.40% on LG7. Combined with RNA sequencing (RNA-seq), one structural gene VlEDR2 (Vitvi02g00982) and three transcription factors VlERF039 (Vitvi00g00859), VlNAC047 (Vitvi08g01843), and VlWRKY51 (Vitvi07g01847) that may be involved in VlEDR2 expression and grape gray mold resistance were selected. This discovery of candidate gray mold resistance genes will provide an important theoretical reference for grape gray mold resistance mechanisms, research, and gray mold-resistant grape cultivar breeding in the future.

Phosphorus critical levels in soil and grapevine leaves for South Brazil vineyards: A Bayesian approach

In South Brazil, grapevines (Vitis vinifera L.) have been grown in acid sandy soils, increasing phosphorus (P) need for fertilization. However, current fertilizer guidelines for growers are based on Vitis labrusca grown in clay soils. Therefore, there is a clear need to provide new recommendations on fertilization in vineyards. This study aimed to: (i) establish critical levels (CL) for P in the soil and grape leaves at flowering and veraison growth stages; and (ii) propose P maximum technical efficiency (MTE) rates for white and red grapevines grown in sandy soils based on a Bayesian approach. The study was carried out in sandy soil in South Brazil, with six P fertilization rates (0, 10, 20, 40, 60, and 100 kg P2O5 ha−1) applied annually from 2011 to 2015. Grape yield, P concentration in both soil and leaves (at flowering and veraison), and grape composition were measured during three growing seasons (2016, 2017, and 2018). The CL of P in the soil was 37 mg dm−3. This study is the first to propose CL for grapevine leaves at flowering (1.63 g kg−1) and at veraison for white (1.12 g kg−1) and red (1.38 g kg−1) grapevine cultivars in Brazil. Lastly, we proposed MTE rates for ‘Chardonnay’ (42 kg P2O5 ha−1) and ‘Pinot Noir’ (66 kg P2O5 ha−1). This new information provides foundational knowledge to reduce the rate of P fertilization up to 60 % for ‘Chardonnay’ vineyards. The utilization of this Bayesian approach has relevant implications for defining the optimal P management to be applied to vineyards around the globe.

The impact of host plant species on instar duration and body weight of nymphal Lycorma delicatula.

The spotted lanternfly, Lycorma delicatula (White) (Hemiptera: Fulgoridae), is an invasive species of planthopper that was introduced to North America and is a threat to multiple industries. Nymphs and egg masses were collected to assess each instar's rate of development at a constant temperature of 25°C on the following hosts: Ailanthus altissima (Miller) (Sapindales: Simaroubaceae), Vitis labrusca (L.) (Vitales: Vitaceae), Salix babylonica (L.) (Malpighiales: Salicaceae), Acer rubrum (L.) (Sapindales: Sapindaceae), Celastrus orbiculata (Thunberg) (Celastrales: Celastraceae), Ocimum basilicum (L.) (Lamiales: Lamiaceae), and Rosa multiflora (Thunberg) (Rosales: Rosaceae). Host plant species was found to have a significant effect on developmental time for nymphs in the first through third instars, as well as on nymphal survival. Nymphs failed to develop through the second instar on O. basilicum and the third and fourth instars on A. rubrum. Host plant species also had a significant effect on the mean weight of nymphs in the first, second, and fourth instars (but not in the third instar), and on the hind tibia length and forewing width of adult nymphs. This variability in L. delicatula developmental time by host plant species can potentially impact phenology models, which should be updated to reflect these new insights. Rearing practices should also be refined to account for host plant influences on the physiology of L. delicatula.

Determination of some quality properties and antimicrobial activities of kombucha tea prepared with different berries

Kombucha is a slightly sweet, acidic, carbonated, fermented beverage obtained by fermenting sugared tea (Camellia sinesis) with symbiotic bacteria. In the present study, kombucha was produced from black tea (Camellia sinensis), black grape (Vitis labrusca), black mulberry (Morus nigra), and rosehip (Rosa canina) fruits. Its physicochemical, microbiological, sensory properties and antimicrobial effects were investigated. During the fermentation, pH, Brix (%), viscosity, total antioxidant, and phenolic substance values decreased (p < 0.05). Total aerobic mesophilic bacteria (TAMB) and yeast/mold, Lactococcus/Streptococcus counts decreased, while the osmophilic yeast, acetic acid, and lactic acid bacterial counts increased (p < 0.05). The samples produced using black mulberry had the highest antibacterial activity (26.58 mm zone diameter), lowest minimum inhibitory concentration (MIC) (0.012 mg·L$^{-1}$), and minimum bactericidal concentration (MBC) (0.008 mg·L$^{-1}$) on Staphylococcus aureus. The highest antifungal activity was in the rosehip on Mucor racemosus (p < 0.05). The a* values increased during fermentation, while L* and b* values decreased. Based on the sensory analysis, black mulberry was the most preferred sample concerning all assessment criteria.

Performance of ‘BRS Magna’ vines grown under different training systems, rootstocks and production cycles

Over the past decade, the business of producing juice from grapes (Vitis labrusca L. and hybrids) has been expanding in response to increasing consumption encouraged by campaigns promoting the benefits grape juice can have on health. This study aimed to determine the effect of the production cycle, vine training system, and rootstock on the yield and physical and physical-chemical characteristics of ‘BRS Magna’ grapes grown in the Vale do Submédio São Francisco in the northeastern region of Brazil. The study was conducted in Petrolina, Pernambuco, over eight production cycles (2017 to 2020). The grapevines were trained in three vine training trellis systems: espalier, lyre, and pergola; and grafted onto two rootstocks: IAC 572 and IAC 766. The production cycle, training system, and rootstocks affected the yield components, vigor, and physical characteristics of the BRS Magna grapes. The combination of the pergola training system and rootstock IAC 766 stood out from the others, providing mean yields estimated at 26 t ha –1 per production cycle. The soluble solids content (SS), titratable acidity (TA), and SS TA –1 ratio were affected neither by the training system nor the rootstock, and higher values for SS and lower values for TA were obtained in the first, second, fourth and eighth production cycles. Thus, the pergola training system and rootstock IAC 766 are recommended for promoting yield gains in the ‘BRS Magna’ grape in the Vale do Submédio São Francisco.

VvAGAMOUS Affect Development of Four Different Grape Species Ovary

Grape pistil has an important influence on fruit size and quality. However, there were few studies on grape ovary, and the development process of the ovary is still unclear. Therefore, in this paper, four different grape varieties with different lengths of small inflorescences, namely ‘Musct Hambourg’ grape (Vitis vinifera), ‘Concord’ grape (Vitis labrusca), ‘ShanPuTao’ grape (Vitis amurensis) and ‘GongNiang2Hao’ grape (Vitis amurensis × Vitis vinifera) were used as test materials. Four varieties ovary were significant differences by means of stereomicroscope, paraffin section. The expression of ovary determining gene VvAGAMOUS (VvAG) and its development related genes VvCRABS CLAW (VvCRC) and VvAGAMOUS-LIKE 11 (VvAGL11) with similar functions during the development of different grape varieties were preliminarily explored using fluorescence quantitative test. The relationship between VvAG and VvCRC, VvAG and VvAGL11 were analyzed using Y1H assay. Our results showed that there were obvious abdominal sutures on the surface of expect for ‘Musct Hambourg’ grape, and existing poly carpels. The ovary development of ‘ShanPuTao’ and ‘GongNiang2Hao’ grape was completed when the inflorescence length was less than 1 cm, while the ‘Concord’ and ‘Musct Hambourg’ grape were fully developed when the length of inflorescence was 3–4 and 4–5 cm, respectively. VvAG and VvCRC began to express in large quantities after the formation of stamen primordia, while VvAGL11 during the forming of ovule primordia. Therefore, VvAG and VvCRC mainly regulated the development of stamens and carpels and also promote the development of ovules, while VvAGL11 major regulated the development of ovules. The promoters of VvCRC and VvAGL11 were bound by VvAG. This study provides an important theoretical basis for further research on the molecular mechanism of grape ovary development.

Metabolic engineering of Rhodotorula toruloides for resveratrol production

BackgroundResveratrol is a plant-derived phenylpropanoid with diverse biological activities and pharmacological applications. Plant-based extraction could not satisfy ever-increasing market demand, while chemical synthesis is impeded by the existence of toxic impurities. Microbial production of resveratrol offers a promising alternative to plant- and chemical-based processes. The non-conventional oleaginous yeast Rhodotorula toruloides is a potential workhorse for the production of resveratrol that endowed with an efficient and intrinsic bifunctional phenylalanine/tyrosine ammonia-lyase (RtPAL) and malonyl-CoA pool, which may facilitate the resveratrol synthesis when properly rewired.ResultsResveratrol showed substantial stability and would not affect the R. toruloides growth during the yeast cultivation in flasks. The heterologus resveratrol biosynthesis pathway was established by introducing the 4-coumaroyl-CoA ligase (At4CL), and the stilbene synthase (VlSTS) from Arabidopsis thaliana and Vitis labrusca, respectively. Next, The resveratrol production was increased by 634% through employing the cinnamate-4-hydroxylase from A. thaliana (AtC4H), the fused protein At4CL::VlSTS, the cytochrome P450 reductase 2 from A. thaliana (AtATR2) and the endogenous cytochrome B5 of R. toruloides (RtCYB5). Then, the related endogenous pathways were optimized to affect a further 60% increase. Finally, the engineered strain produced a maximum titer of 125.2 mg/L resveratrol in YPD medium.ConclusionThe non-conventional oleaginous yeast R. toruloides was engineered for the first time to produce resveratrol. Protein fusion, co-factor channeling, and ARO4 and ARO7 overexpression were efficient for improving resveratrol production. The results demonstrated the potential of R. toruloides for resveratrol and other phenylpropanoids production.

Polyphenols, organic acids, and their relationships in red grapes of Vitis vinifera and Isabella (Vitis labrusca) under arid conditions

Polyphenols, organic acids, and their relationships in red grapes of Vitis vinifera and Isabella (Vitis labrusca) under arid conditions

Application of different pre-fermentation techniques in the winemaking using Guankou table grape (Vitis vinifera × Vitis labrusca)

The study produces white wines with the table grape (Guankou grape, Vitis vinifera × Vitis labrusca) using different pre-fermentation techniques to reduce bitterness and enhance aroma. Pre-fermentation techniques included pressing levels, low-temperature maceration, ultralow temperature freezing, hyperoxidation, and their different combinations. The compounds were analyzed by ultraperformance liquid chromatography (UPLC) and solid-phase microextraction (SPME) coupled with gas chromatography-mass spectrometric (GC-MS) analysis. The results shown that different pre-fermentation techniques influence the extraction of phenolic and aroma compounds, further forming different sensory qualities. The more damaging process increases the bitter phenols and unpleasant aroma compounds. Flavonoids, tartaric acid esters, and gallic acid esters caused bitterness, and 2,5-bis(1,1-dimethylethyl)-phenol mainly generated aromas of stone fruits. Finally, the results of the comprehensive evaluation of the sensory analysis suggested that after destemming and maceration (4 ± 1 °C, for 24 h), the most aromatic wines are fermented with pressed juice (pressure from 0.5 to 1.0 bar),and the most harmonious wines are fermented with free juice. The study provides a strong basis for winemaking with table grapes.

Microencapsulated phenolic-rich extract from juice processing grape pomace (Vitis labrusca. Isabella Var): Effects on oxidative stability of raw and pre-cooked bovine burger

Grape processing generates residues rich in bioactive compounds with potential application in the meat industry. However, these substances are unstable and needs to be treated to allow their action during the processing and storage of meat products. In this sense, a phenolic-rich extract from grape pomace was microencapsulated and evaluated for its potential to inhibit the oxidative process in raw and precooked beef burgers during cold storage. Three hamburger formulations containing lyophilized extract (LEB), microencapsulated extract (MEB) and synthetic antioxidant sodium erythorbate (SEB) were prepared, pre-cooked, and evaluated for lipid and protein oxidation. The microencapsulation, with 95.0% efficiency, provided a material with a crystalline structure, rich in phenolics and with high antioxidant potential, showing 377.4 ± 0.01, 1768.1 ± 0.07 and 1185.0 ± 0.20 μmol TEAC.100 g−1 for DPPH, ABTS and FRAP, respectively. Lower values of malonaldehyde were found in LEB and MEB (2.9 ± 0.3 and 1.4 ± 0.5 mg MDA.kg−1, respectively) at the end of storage, with emphasis on for the hamburgers that received the microencapsulated extract. Similar behavior was observed for the analysis of carbonyl compounds, with values of 11.1 ± 1.1, 8.7 ± 1.4 and 6.8 ± 1.0 nM carbonyl.mg−1 in SEB, LEB and MEB, respectively. Thus, the freeze-dried and microencapsulated grape extracts showed superior results when compared to the synthetic antioxidant, increasing the oxidative stability of hamburgers, and avoiding significant color changes during the cold storage. The results indicate the high potential of the microencapsulated material to be used as a natural antioxidant in the meat industry.

Phytochemical profile of Brazilian grapes (Vitis labrusca and hybrids) grown on different rootstocks.

Important factors may influence the bioactive compounds in grapes, including scion–rootstock interaction. Therefore, the bioactive compounds and antioxidant activity in grape skin and pulp fractions of ‘Isabel Precoce’, ‘BRS Carmem’, ‘BRS Cora’, ‘BRS Violeta’ and ‘IAC 138–22 Máximo’ were assessed. These cultivars, from genetic improvement programs in Brazil, have good adaptation to subtropical and tropical climate conditions, and can be widely used by winegrowers aiming at adding value to the grape. All grapevines were grafted onto ‘IAC 766’ and ‘IAC 572’ rootstocks under tropical conditions in Brazil. The highest concentration of bioactive compounds was found in skins of ‘BRS Violeta’, followed by ‘IAC 138–22 Máximo’, both grafted onto ‘IAC 766’. There was a strong correlation between phenolic content and antioxidant properties, since antioxidant activity also decreased in the sequence: ‘BRS Violeta’ > ‘IAC 138–22 Máximo’ > ‘BRS Cora’ > ‘BRS Carmem’ > ‘Isabel Precoce’. Skin from hybrid grapes (‘BRS Violeta’, ‘IAC 138–22 Máximo’, ‘BRS Cora’ and ‘BRS Carmem’) grafted in both rootstocks contains higher levels of (poly)phenolic compounds and antioxidant activity than ‘Isabel Precoce’ (V. labrusca). Skin from ‘BRS Violeta’ grafted onto ’IAC 766’ stand out from the others due to their high content of bioactive compounds.