Centennial Seedless Research Articles

Agrobiological reaction of Centennial Seedless grape variety to changes in the numberof shoots and bunches on bushes

Agrobiological reaction of Centennial Seedless grape variety to changes in the numberof shoots and bunches on bushes

МЕТОДОЛОГИЯ УПРАВЛЕНИЯ АГРОБИОЛОГИЧЕСКОЙ, АДАПТИВНОЙ И ПРОДУКЦИОННОЙ УСТОЙЧИВОСТЬЮ НАСАЖДЕНИЙ ВИНОГРАДА В НЕСТАБИЛЬНЫХ ПОГОДНЫХ УСЛОВИЯХ И ТЕХНОГЕННОЙ ИНТЕНСИФИКАЦИИ ПРОИЗВОДСТВА

The article presents the results of agrobiological and physiological-biochemical studies to ensure the stability of grape plantations in unstable weather conditions and anthropogenic intensification of production. Studies in the agroecological conditions of the Krasnodar region on the southern chernozems revealed the most productive norm of loading of grape bushes with shoots for the technical varieties Kurchanskiy, Dmitriy, Vladimir, Granatovyi, Antaris and Alkor, on leached chernozems – for the table seedless variety Centennial Seedless. According to the results of electrophoretic separation of peroxidases in polyacrylamide gel and an increased content of ascorbic acid, increased frost resistance was established in the varieties Kristall, Vostorg, Krasnostop AZOS. The Vostorg and Zarif varieties proved to be more adaptive to the stresses of the summer period in terms of leaf hydration, bound water content, the ratio of chlorophylls and carotenoids, the amount of proline and water-soluble sugars, membrane permeability. The role of physiologically active substances in increasing the adaptive potential of grape plants has been established. The treatment of Merlot vines with methyl jasmonate and epibrassinolide during deep dormancy period, as well as proline, salicylic acid and epibrassinolide during induced dormancy period had a positive effect on the condition of the vine: there was a decrease in electrolyte yield. Sustainable grape cultivation is achieved with the systemic use of the «Bioconcentrate-Z» effluent by the non-root method. Against the background of nonroot treatments of Merlot and Cabernet Sauvignon varieties, a higher level of plant water supply, an increase in potassium content, green pigments, organic acids and grape yields were established. Physiologically active compounds and the preparation Turinbash have a positive effect in intensive own-root plantations of native and promising introduced grape varieties against the background of phylloxera infection in the southern part of Dagestan. The created yield forecasting method based on the NDVI of the grape plant and the actual data of multispectral images of the phenophases of flowering and growth allows to increase the accuracy of the calculated yield capacity to the actual one with a deviation from 0 to 0.8 kg per bush, the accuracy of the forecast increases by 2 times by the end of the growth phase and by the beginning of the maturation phase. Key words: GRAPES, METHODS, MANAGEMENT, SUSTAINABILITY, PRODUCTIVITY, QUALITY, FORECASTING

РЕАКЦИЯ СОРТА CENTENNIAL SEEDLESS НА НАГРУЗКУ КУСТОВ ПОБЕГАМИ И ГРОЗДЯМИ В УСЛОВИЯХ ЦЕНТРАЛЬНОЙ АГРОЭКОЛОГИЧЕСКОЙ ЗОНЫ ВИ-НОГРАДАРСТВА ПО ФИЗИОЛОГИЧЕСКИМ КРИТЕРИЯМ

The article considers the issue of the influence of the different loads of bushes with shoots and bunches on the physiological state of the leaves of Centennial Seedless grape variety in the agroecological conditions of the Central viticul-ture zone of the Krasnodar region. The Centen-nial Seedless variety is cultivated in a covering and grafted culture on a SO4 rootstock, drip irrigation. Climate is moderately continental, the soils are low-humus, leached powerful cherno-zems. The assessment of the physiological state of Centennial Seedless grape plants was carried out according to the variants of differentiated load by shoots and bunches (high, medium and low) according to the following parameters: quantum yield of photosynthesis, chlorophyll a and b content, carotenoids, relative water con-tent in leaves, water content in leaves and elec-trolyte leakage. In the studied summer months, the average air temperature was +24.3 °C, which is 0.4 °C above the climatic norm, the maximum temperatures rose to +35 °C. The total precipita-tion was 132 mm higher than normal due to heavy rains in some decades. The physiological and biochemical parameters of the leaves of the Centennial Seedless grape variety during the summer period were within the normal range – the quantum yield was above 0.7, the relative water content in the leaves was above 85 %, the water content was above 70 % except in Au-gust, the amount of chlorophylls a and b was above 1 except for the variant with the average load in July, the electrolyte leakage varied from 7.3 % to 17.3 %. In August, during the period of the greatest temperature stress for the leaves, the variant with a high load of bushes with shoots and bunches proved to be the best.

РЕАКЦИЯ СОРТА КИШМИШ СТОЛЕТИЕ НА НАГРУЗКУ КУСТОВ ПОБЕГАМИ И ГРОЗДЯМИ В УСЛОВИЯХ ЦЕНТРАЛЬНОЙ АГРОЭКОЛОГИЧЕСКОЙ ЗОНЫ ВИНОГРАДАРСТВА ПО КАЧЕСТВЕННЫМ КРИТЕРИЯМ

The presence of organic acids and cations, amino acids, sugars and other substances in grapes and products of its processing affects their taste and nutritional properties. The pools of these substances were studied in grapes of the Centennial Seedless variety with different bush load with shoots and bunches. To determine the composition and content of these substances in grape juice, classical instrumental methods and a capillary electrophoresis system, “Kapel-104T” and “Kapel-105M”, OOO NPF “LUMEX”, were used. Tartaric, acetic and malic acids have been identified in the juice. Significant contents of resveratrol, ascorbic, chlorogenic, nicotinic, orotic acids, proline, valine, and α-alanine were also found. The highest concentrations were observed in the variant with an average bush load with shoots and bunches.

The Impact of High Temperatures in the Field on Leaf Tissue Structure in Different Grape Cultivars

Global warming will significantly affect grapevine growth and development. To analyze the effects of high temperature on the leaf tissue structure of grapevines in the field, 19 representative cultivars were selected from the grapevine germplasm resources garden in Turpan Research Institute of Agricultural Sciences, XAAS. Twelve tissue structure indexes of grapevine leaves, including the thickness of the upper epidermis (TUE), the thickness of palisade tissue (TPT), leaf vein (LV), the thickness of spongy tissue (TST), the thickness of the lower epidermis (TLE), stoma (St), guard cell (GC), cuticle (Cu), leaf tissue compactness (CTR) and leaf tissue porosity (SR), were measured during the natural high-temperature period in Turpan. The results showed significant differences in the leaf tissue structure of the 19 grapevine cultivars under natural high temperature. Based on the comprehensive comparative analysis of the leaf phenotype in the field, we identified that the leaves of some cultivars, including ‘Zaoxia Wuhe’, ‘Centennial Seedless’ and ‘Kyoho’ showed strong heat tolerance, whereas grapevine cultivars ‘Golden Finger’, ‘Shine Muscat’, ‘Flame Seedless’, ‘Bixiang Wuhe’ and ‘Thompson Seedless’ showed sensitivity to high temperature. We further evaluated the heat tolerance of different grapevine cultivars by principal component analysis and the optimal segmentation clustering of ordered samples. These findings provide a theoretical basis for adopting appropriate cultivation management measures to reduce the effect of high temperatures and offer fundamental knowledge for future breeding strategies for heat-tolerant grapevine varieties.

Preparation technology and preservation mechanism of γ-CD-MOFs biaological packaging film loaded with curcumin

To prevent food spoilage caused by microbial infection, the development of an environmentally friendly antimicrobial preservation material is crucial. Here, the microporous γ-CD-MOFs was utilized to encapsulate the hydrophobic active substance curcumin, resulting in the preparation of a non-toxic antimicrobial material (Cur-CD-MOFs). The results revealed that curcumin encapsulation in Cur-CD-MOFs occurred primarily in the carbonyl group, benzene ring, and enolic side ring of curcumin. The Cur-CD-MOFs had a 100% bactericidal effect on Escherichia coli and Staphylococcus aureus at 4 h and 8 h, and a strong inhibitory effect on aerial mycelium of Penicillium expansum and Botrytis cinerea. Furthermore, the incorporation of Cur-CD-MOFs improved the Pul/Tre film barrier and mechanical properties. The effectiveness of Cur-CD-MOFs-Pul/Tre in retaining fruit freshness was validated using Centennial Seedless grapes. This study confirmed that Cur-CD-MOFs is a promising antibacterial material, and Cur-CD-MOFs-Pul/Tre will be a potent candidate for food preservation.

ВЛИЯНИЕ РАЗЛИЧНОЙ НАГРУЗКИ КУСТОВ ПОБЕГАМИ И ГРОЗДЯМИ НА УВОЛОГИЧЕСКИЕ ПОКАЗАТЕЛИ СОРТА ВИНОГРАДА CENTENNIAL SEEDLESS

The article considers the issue of the influence of the different loads of bushes with shoots and bunches on the uvological indicators of bunches of Centennial Seedless grapevine variety in the agroecological conditions of the Central viticulture zone of the Krasnodar region. The Centennial Seedless variety is cultivated in a covering and grafted culture on a SO4 rootstock. Drip irrigation. The soils are low-humus, leached powerful chernozems. The average air temperature of the winter months (December-February) of the studied 2021/2022 was 2.3 °C higher than the climatological norm of 1991‒2020. The absolute minimum was observed in the third decade of December and amounted to 13 °C. The transition of air temperature through +10 °C occurred on March 31. The average temperature of the growing season (April-September) was +20.1 °C, 0.1 °C less than climatological norm. The absolute maximum air temperature was observed in the second decade of September – +38 °C, which is extremely atypical for this area. The total precipitation was 77 mm more than climatological norm and amounted to 427 mm. Uvological assessment of bunches was carried out in three variants of the bush load with shoots and bunches: variant 1 (control) – the maximum load with shoots (36 pcs./bush) and bunches (27 pcs./bush); variant 2 – the average load with shoots (23 pcs./bush) and bunches (15 pcs./bush); variant 3 – minimum load of shoots (13 pcs./bush) and bunches (8 pcs./bush). During the uvological analysis of grape bunches a variant with an average bush load with shoots (23 pcs./bush) and bunches (15 pcs./bush) highlighted according to the following parameters: length and width of the bunch, average berry weight, proportion of berries and stalks in the bunch, number of berries per 100 g of bunch, average weight of 100 berries, pulp weight in 100 berries. The variant with the maximum load of bushes with shoots (36 pcs./bush) and bunches (27 pcs./bush) highlighted by weight of bunches, the weight of pulp and rudiments in a bunch, the number and weight of rudiments in a berry, the average weight of rudiments in 100 berries. The variant with the least load of bushes with shoots (13 pcs./bush) and clusters (8 pcs./bush) highlighted by weight and the proportion of skin and pulp.

Genetic differences as estimators of osmotic adjustment and source-sink balance in grapevine hybrid elites

This study deals with the best responses of a diverse collection of grapevine genotypes to osmotic stress associated with source-sink balance responses given by an estimator such as leaf area to fruit ratio. ‘Centennial Seedless’, a drought tolerant cultivar, was selected as control. The cultivars, ‘Victoria’ and ‘Argessis’, were chosen as a repetition from previous research dealing with pollen grain test, two years ago. Ten genotypes were hybrid elites in first and second hybrid generations. Three cultivars ‘Victoria’, ‘Centennial Seedless’, and ‘Argessis’ were grown under field conditions in containers, and in the soil under greenhouse conditions. Significant differences were found between genotypes for both responses to osmotic stress and source-sink balance. ‘Centennial Seedless’ and ‘BP9’ hybrid showed the best responses of induced osmotic adjustment; results confirmed the compensatory potassium uptake theory. ‘Victoria’ and ‘Argessis’ had almost the same average values as ‘Centennial Seedless’ osmotic estimator for induced osmotic adjustment. ‘Victoria’ and ‘HR7’ hybrid showed an increase in osmotic stress in the cell, after application of polyethylene glycol solutions without potassium cation and a lower source-sink ratio, which could be associated with higher photosynthesis rates. No correlations were identified between the mechanisms expressed by the analyzed estimators, indicating that they are activated and functional separately from each other, sometimes only compensatory.

QTL-seq analysis of the seed size trait in grape provides new molecular insights on seedlessness

Seedlessness in grape (Vitis vinifera) is an important commercial trait for both the fresh and drying markets. However, despite numerous studies, the mechanisms and key genes regulating grape seedlessness are mostly unknown. In this study, we sequenced the genomes of the V. vinifera seeded cultivar ‘Red Globe’, the seedless cultivar 'Centennial Seedless’, and the derived hybrids. Nonsynonymous single nucleotide polymorphisms (SNPs) were identified by genome sequencing and analyzed using published transcriptome data. Nonsynonymous SNPs occurred in genes related to seed development, which were identified as protein kinases, transcription factors, and cytochrome P450s and showed differential expression during ovule development in both seeded and seedless grapes. These nonsynonymous SNP-associated genes were mainly involved in biological processes such as hormone balance, seed coat and endosperm development, reproductive organ development, oxidation and reduction, senescence and cell death. A potential quantitative trait locus (QTL) region associated with seed size was characterized based on the SNP-index, and expression analysis of candidate genes in the QTL region during ovule development in multiple seeded and seedless grape cultivars were conducted. Three SNPs were further subjected to SNaPshot analysis and one SNP in G8 showed 67.5% efficiency in the grape progeny validation. Overall, the data obtained in this study shed light on the differences in seed development between seeded and seedless progeny at the genomic level, which provides valuable resources for future functional studies and grape breeding.

Comparison of sugars, organic acids and aroma components of five table grapes in Xinjiang

The sugar, organic acid and aroma Components are very important quality characteristics of fruits. In this study, sugars, organic acids and volatile substances in five varieties of Xinjiang table grape pulp were determined by high-performance liquid chromatography and gas chromatography-mass spectrometry. The results showed that among the five varieties of table grapes in Xinjiang, fructose and glucose were the main sugars, accounting for 46.53-48.82% and 49.35-51.49% of the total sugar content, respectively. Tartaric acid and malic acid were the main organic acids, accounting for 55.72-60.07% and 28.54-39.52% of the total organic acids, respectively. The composition of sugars and organic acids ratio plays a significant role in the taste of table grapes. The sweetness of Red Globe was the highest while the acidity of Centennial Seedless was the highest. In addition, 87 varieties of volatile compounds were identified in table grape pulp with aldehydes as the major compounds (30.93-71.83%). In particular, trans-2-hexenal accounted for 19.33-44.56% of the total volatiles. Analysis of active odorants showed that nerol, geraniol, (Z)-3-hexenal, trans-2-hexenal, phenylacetaldehyde, citral and β-myrcene had great contributions to the flavors of Centennial Seedless and Muscat Hamburg, providing flowery, fruity, green and grassy flavors. Hexanol, trans-2-hexen-1-ol, damascone and ethyl butyrate had great contributions to the flavors of Rizamat, providing flowery, green and fruity flavors. Nonanal and 1-octen-3-one had great contributions to the flavors of Manaizi, providing mushroom and fruity flavors. The results provided the complete chemical characteristics of sugar, organic acids and volatile compounds of five varieties of table grapes in Xinjiang, China.

Drying Treatments Change the Composition of Aromatic Compounds from Fresh to Dried Centennial Seedless Grapes.

Raisin aroma is a vital sensory characteristic that determines consumers’ acceptance. Volatile organic compounds (VOCs) in fresh grapes, air-dried (AD), pre-treated air-dried (PAD), sun-dried (SD), and pre-treated sun-dried (PSD) raisins were analyzed, with 99 and 77 free- and bound-form compounds identified in centennial seedless grapes, respectively. The hexenal, (E)-2-hexenal, 1-hexanol, ethyl alcohol, and ethyl acetate in free-form while benzyl alcohol, β-damascenone, gerenic acid in bound-form were the leading compounds. Overall, the concentration of aldehydes, alcohols, esters, acids, terpenoids, ketones, benzene, and phenols were abundant in fresh grapes but pyrazine and furan were identified in raisin. Out of 99 VOCs, 30 compounds had an odour active value above 1. The intensity of green, floral, and fruity aromas were quite higher in fresh grapes followed by AD-raisins, PAD-raisins, SD-raisins, and PSD-raisins. The intense roasted aroma was found in SD-raisins due to 2,6-diethylpyrazine and 3-ethyl-2,5-dimethylpyrazine. Among raisins, the concentration of unsaturated fatty acid oxidized and Maillard reaction volatiles were higher in SD-raisins and mainly contributed green, fruity and floral, and roasted aromas, respectively.

Candidate resistance genes selection and transcriptome analysis for the early responses to Plasmopara viticola infection in grape cultivars

Grape downy mildew (Plasmopara viticola) is one of the most destructive diseases of grapevine worldwide. In order to better understand the cellular processes involved in resistance to downy mildew, leaves of Vitis vinifera cv. ‘Centennial Seedless’ (susceptible) and Vitis labrusca×Vitis riparia cv. ‘Beta’ (resistant) were inoculated with Plasmopara viticola, and were used in the Illumina HiSeq™2000 platform for deep transcriptome sequencing. We performed transcriptome analysis and identified a total of 1091 differentially expressed genes (DEGs) in the disease-resistant cultivar and 849 in the susceptible cultivar. To increase understanding of the DEGs, the datasets were analyzed using Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genome (KEGG) database. Most of them were found to be associated with plant–pathogen interaction, flavonoid synthesis, phenylpropanoid synthesis metabolism and phytohormone signal transduction. Moreover, transcription factors ERF, MYB, WRKY, and bHLH associated with disease resistance were screened. A total of 196 genes were identified as the candidate resistant genes. The expression of 18 differentially expressed genes was detected by RT-qPCR. Finally, the pattern of differentially expressed genes was consistent with the result of transcriptome sequencing. The present study identified several candidate resistance genes and signal transduction pathways that may contribute to downy mildew resistance in grapes.

Crude garlic extract significantly inhibits replication of grapevine viruses

Efforts to control viral diseases of grapevine include the production of certified material and development of virus‐resistant transgenic grapevines. However, effective antiviral agents, once the viruses have infected the plants, are still lacking. This study shows that a crude garlic extract has significant antiviral activity against grapevine viruses. Replication of grapevine leafroll‐associated virus 2 (GLRaV‐2) was obviously inhibited in grapevine cv. Cabernet Sauvignon calli treated with diluted (1:100) garlic extract. The relative RNA levels of GLRaV‐2 and grapevine fleck virus (GFkV) in cv. Summer Black grapevine in in vitro‐grown plantlets 10 days after treatment with diluted (1:100) garlic extract were about 22% and 20%, respectively, of that in controls. The viral RNA accumulation of GLRaV‐2, GFkV, grapevine virus A (GVA), grapevine fanleaf virus (GFLV) and grapevine rupestris stem pitting‐associated virus (GRSPaV) in field‐grown grapevine cv. Centennial Seedless plants sprayed with diluted (1:100) garlic extract were about 31–40%, 26–38%, 18–31%, 17–42% and 15–18%, respectively, of that in controls. Moreover, the garlic extract treatment led to a significant decrease in viral RNA accumulation of GLRaV‐3, GLRaV‐2, GVA, GFkV, GFLV, GRSPaV and grapevine Pinot Gris virus in pot‐grown grapevine cv. Shine Muscat plants, and viral disease symptoms in these plants were obviously attenuated. In addition, this extract significantly induced expression of pathogenesis‐related protein genes and stimulated activity of antioxidant enzymes in grapevines. Taken together, these results indicate that the crude garlic extract acts as a significant inhibitor against a broad range of grapevine viruses.

Green Grape Detection and Picking-Point Calculation in a Night-Time Natural Environment Using a Charge-Coupled Device (CCD) Vision Sensor with Artificial Illumination.

Night-time fruit-picking technology is important to picking robots. This paper proposes a method of night-time detection and picking-point positioning for green grape-picking robots to solve the difficult problem of green grape detection and picking in night-time conditions with artificial lighting systems. Taking a representative green grape named Centennial Seedless as the research object, daytime and night-time grape images were captured by a custom-designed visual system. Detection was conducted employing the following steps: (1) The RGB (red, green and blue). Color model was determined for night-time green grape detection through analysis of color features of grape images under daytime natural light and night-time artificial lighting. The R component of the RGB color model was rotated and the image resolution was compressed; (2) The improved Chan–Vese (C–V) level set model and morphological processing method were used to remove the background of the image, leaving out the grape fruit; (3) Based on the character of grape vertical suspension, combining the principle of the minimum circumscribed rectangle of fruit and the Hough straight line detection method, straight-line fitting for the fruit stem was conducted and the picking point was calculated using the stem with an angle of fitting line and vertical line less than 15°. The visual detection experiment results showed that the accuracy of grape fruit detection was 91.67% and the average running time of the proposed algorithm was 0.46 s. The picking-point calculation experiment results showed that the highest accuracy for the picking-point calculation was 92.5%, while the lowest was 80%. The results demonstrate that the proposed method of night-time green grape detection and picking-point calculation can provide technical support to the grape-picking robots.

Changes of free-form volatile compounds in pre-treated raisins with different packaging materials during storage

The aroma profiles of volatile compounds (VOCs) were analyzed by GC/MS in pre-treated air-dried (PAD) and sun-dried (PSD) raisins during storage. Total 98, 94 and 81 VOCs were identified in Zixiang Seedless raisins (ZSRs), Centennial Seedless raisins (CSRs) and Thompson Seedless raisins (TSRs), respectively. During storage, the overall concentrations of VOCs of PSD raisins were higher in plastic bag (PB) compared to those in woven bag (WB). Regarding fruity and floral aromas, the effect of PAD and PB was significant throughout the storage periods (3, 6 and 9 months), however, fatty aroma was higher in PSD raisins due to the major contribution of 2,3-butanedione. The main fruity and floral aroma contributors were β-damascenone, limonene, rose oxide, geraniol and ethyl hexanoate. This study showed that compounds came from unsaturated fatty acid oxidation, glycosidically-derived and grape-derived source were contributed to fruity, floral or herbaceous aromas, but Maillard reaction-derived VOCs imparted fatty and roasted aromas.

Chemical composition, bioactive compounds, and volatiles of six table grape varieties (Vitis vinifera L.)

Six table grape cultivars (Centennial Seedless, Chasselas, Italia, Italia Rubi, Alphonse Lavallée, and Muscat de Hambourg) were analyzed for their levels of soluble solids, titratable acidity, sugars, organic acids, vitamin C and E, carotenoids, polyphenolics and volatile compounds during two successive years. Descriptive sensory analyses of the six table grape varieties were also performed. Mainly due to anthocyanins, black cultivars had the highest total phenolic contents. Alphonse Lavallée had also both the highest levels of trans-resveratrol and piceid, and Muscat de Hambourg the highest levels of α-tocopherol, β-carotene and monoterpenols, well-known key aroma compounds in Muscat varieties having also interesting pharmacological properties. This study shows that the two traditional black French cultivars, Muscat de Hambourg and Alphonse Lavallée, are particularly rich in bioactive compounds and have a great potential for human health. Finally, Muscat de Hambourg was significantly rated sweeter, juicier and more aromatic than the others cultivars.

A SNP in the promoter region of theVvmybA1 gene is responsible for differences in grape berry color between two related bud sports of grape

The VvmybA1 gene in grape (Vitis vinifera) plays a key role in the biosynthesis of anthocyanin. The grape cultivars, ‘Benitaka’ (red color) and ‘Brazil’ (black color) were the result of a bud mutation. ‘Benetika’ was derived from ‘Italia’ (green color) and ‘Brazil’ was developed from ‘Benetika’. Single sequence repeat (SSR) molecular marker analysis was performed in order to demonstrate that the three cultivars have a common pedigree. A sequence analysis of the promoter region and coding sequence of VvmybA1 revealed a base substitution between ‘Benitaka’ and ‘Brazil’ in the promoter region and a deletion of a large DNA fragment in the promoter region of ‘Italia’. Anthocyanin content and expression of the VvmybA1 and UFGT genes in ‘Brazil’ were higher than in ‘Benitaka’ and barely detectable in ‘Italia’. A transient expression system was used to introduce VvmybA1 driven by the three different promoters present in ‘Italia’, ‘Brazil’, and ‘Benitaka’ into somatic embryos of ‘Centennial Seedless’ (Vitis vinifera L.) by Agrobacterium-mediated transformation. This resulted in the production of red cells in the embryos transformed with the constructs of VvmybA1 from ‘Brazil’ and ‘Benitaka’ and no color production in embryos transformed with the VvmybA1 construct from ‘Italia’. In addition, the embryos transformed with the ‘Brazil’ construct had more red color than the embryos transformed with the ‘Benitaka’ construct. These results suggested that a SNP mutation in the promoter region of VvmybA1 in ‘Benitaka’ (red color) was responsible for the color change displayed by ‘Brazil’ (black color).

Free and glycosidically bound volatile compounds in sun-dried raisins made from different fragrance intensities grape varieties using a validated HS-SPME with GC-MS method.

The conditions of sample pretreatments and HS-SPME for extracting volatile compounds from raisins were optimized, and the method was validated in the study. Free and glycosidically bound volatile compounds in three different fragrance intensities raisins were analysed using this method. There were 91 compounds identified, and 72, 26 and 8 of these compounds came from fresh grapes, the auto-oxidation of unsaturated fatty acids (UFAO) and the Maillard reaction, respectively. The aroma profiles of Thompson Seedless raisins (TSRs) and Centennial Seedless raisins (CSRs) were similar, while the floral, fruity, green and roasted aromas of CSRs were higher than those of TSRs due to the contributions of benzeneacetaldehyde, 2-pentylfuran, (E)-2-nonenal and 3-ethyl-2,5-dimethyl pyrazine. Decanal, rose oxide, geraniol, linalool and β-damascenone made the floral and fruity aromas of Zixiang Seedless raisins (ZSRs) greater than those in TSRs and CSRs, but the green and roasted aroma intensities of ZSRs were lower.

Transcriptome analyses of seed development in grape hybrids reveals a possible mechanism influencing seed size.

BackgroundSeedlessness in grape (Vitis vinifera) is of considerable commercial importance for both the table grape and processing industries. Studies to date of grape seed development have been made certain progress, but many key genes have yet to be identified and characterized.ResultsIn this study we analyzed the seed transcriptomes of progeny derived from the V. vinifera seeded maternal parent ‘Red Globe’ and the seedless paternal parent ‘Centennial seedless’ to identify genes associated with seedlessness. A total of 6,607 differentially expressed genes (DEGs) were identified and examined from multiple perspectives, including expression patterns, Gene Ontology (GO) annotations, pathway enrichment, inferred hormone influence and epigenetic regulation. The expression data of hormone-related genes and hormone level measurement reveals the differences during seed development between seedless and seeded progeny. Based on both our results and previous studies of A. thaliana seed development, we generated network maps of grape seed-related DEGs, with particular reference to hormone balance, seed coat and endosperm development, and seed identity complexes.ConclusionIn summary, the major differences identified during seed development of seedless and seeded progeny were associated with hormone and epigenetic regulation, the development of the seed coat and endosperm, and the formation of seed identity complexes. Overall the data provides insights into the possible molecular mechanism controlling grape seed size, which is of great importance for both basic research and future translation applications in the grape industry.Electronic supplementary materialThe online version of this article (doi:10.1186/s12864-016-3193-1) contains supplementary material, which is available to authorized users.

Red and Blue Lights Significantly Affect Photosynthetic Properties and Ultrastructure of Mesophyll Cells in Senescing Grape Leaves

Light quality significantly affects photosynthetic efficiency in plants. The mechanisms for how light quality affects photosynthesis in grape is poorly understood. Therefore, to investigate the effects of different light qualities on chloroplast ultrastructure and photosynthesis efficiency, two grape cultivars ‘Italia’ (slower speed of leaf senescence) and ‘Centennial Seedless’ (faster speed of leaf senescence) grown under protected and delayed conditions were used. The three treatments, replicated three times, were control (no supplemental lighting), red light and blue light. Chlorophyll content, net photosynthetic rate, and the ratio of Fv/Fm significantly increased in red light relative to the control. The opposite trend was observed in blue light in the early phase of leaf senescence. At later stages, physiological indexes were gradually higher than that of control, resulting in a delay in leaf senescence. Compared to the control, red and blue light both significantly increased the chlorophyll a/b ratio. Electron microscopy showed that blue light caused severe damage to the fine structure of chloroplasts at early stages of leaf senescence, but effects at later stages of leaf senescence became less severe compared to the control. The degradation of chloroplast ultrastructure was apparently delayed in red light throughout the experimental timeframe compared to other treatments. In this experiment, ‘Italia’ showed higher chlorophyll content, net photosynthetic rate, ratios of Fv/Fm, chlorophyll a/b and better preserved chloroplast ultrastructure relative to ‘Centennial Seedless’, resulting in a slower rate of leaf senescence.