Prospect on Ionomic Signatures for the Classification of Grapevine Berries According to Their Geographical Origin

The Application of High-Resolution Melting Analysis to trnL (UAA) Intron Allowed a Qualitative Identification of Apple Juice Adulterations

Food authenticity plays a pivotal role in the modern age since an increased consumers awareness has led them to pay more attention to food commodities. For this reason, it is important to have reliable and fast techniques able to detect possible adulterations in food, which affect qualitative and economic value. Therefore, the aim of this study was to detect possible adulterations in apple juice from others fruit species (i.e., pear, peach, and kiwi) combining DNA barcoding approach, using trnL (UAA) intron, with high resolution melting analysis (HRMA). A preliminary phylogenetic analysis, using sequences retrieved by the GenBank, confirmed the discriminatory power of trnL (UAA) intron among the four fruit species examined. Moreover, the sequencing of the trnL (UAA) fragments obtained from apple, pear, peach, and kiwi, demonstrated the suitability of an inner shorter sequence, P6 loop, to differentiate the considered species. The HRMA coupled with trnL (UAA) intron allowed discrimination among the four fruits but provided incomplete results for juices. Whereas the HRMA targeting the P6 loop amplicons confirmed the suitability of the technique to qualitatively distinguish fruit juices composed by the combination of apple/pear and apple/peach. However, the impossibility of discriminating apple/kiwi juices from the pure kiwi sample highlighted limitations, most likely related to the DNA extraction process. This hypothesis was further confirmed by analyzing DNA blends obtained by combining nucleic acids extracted from pure matrixes (i.e., apple and kiwi fruits). In this specific case, the application of HRMA allowed both qualitative and quantitative assessment of the samples.

Region, vintage, and grape maturity co-shaped the ionomic signatures of the Cabernet Sauvignon wines

The ionic elements in wine and in vineyards are gaining attention due to characterization of the wine traits, wine origin tracing, and vine nutrient judging. In this experiment, 19 elements were detected by inductively coupled plasma mass spectrometry (ICP-MS) in 69 wine samples from 4 regions, 3 vintages, and 3 grape maturity levels. Furthermore, the elements related to vine development, such as N, P, K, Ca, Mg, Cu, Fe, Zn and Cu in the vineyard soil and petioles were determined. Two orthogonal partial least squares discriminant analysis (O2PLS-DA) showed that K, Mn, Co, Sr, B, Si, Pb, Ni, Cu, and Zn were important elements in distinguishing the regions. High-temperature vintages can bring wines with high levels of Sr in wine. Na, Ca, K, Mg, Rb, Al, Rb, Pb and Fe can be used as signature elements to distinguish wines made from 2 grape maturities. And Cu, Zn, and Mn were the key elements used to differentiate the petioles in the 4 regions. Partial square regression (PLSR) analysis showed that soil pH was positively correlated with Al, B, Ba, K, Pb, Mn, Sr and Rb in wine, and K in wine was significantly positively correlated with element K in the soil. In conclusion, the elemental contents in wine are shaped by the combination of origin, vintage and grape maturity, while some key elements can be used as indicators of origin traceability.

Transcriptomic and metabolomic integration as a resource in grapevine to study fruit metabolite quality traits

Transcriptomics and metabolomics are methodologies being increasingly chosen to perform molecular studies in grapevine (Vitis vinifera L.), focusing either on plant and fruit development or on interaction with abiotic or biotic factors. Currently, the integration of these approaches has become of utmost relevance when studying key plant physiological and metabolic processes. The results from these analyses can undoubtedly be incorporated in breeding programs whereby genes associated with better fruit quality (e.g., those enhancing the accumulation of health-promoting compounds) or with stress resistance (e.g., those regulating beneficial responses to environmental transition) can be used as selection markers in crop improvement programs. Despite the vast amount of data being generated, integrative transcriptome/metabolome meta-analyses (i.e., the joint analysis of several studies) have not yet been fully accomplished in this species, mainly due to particular specificities of metabolomic studies, such as differences in data acquisition (i.e., different compounds being investigated), unappropriated and unstandardized metadata, or simply no deposition of data in public repositories. These meta-analyses require a high computational capacity for data mining a priori, but they also need appropriate tools to explore and visualize the integrated results. This perspective article explores the universe of omics studies conducted in V. vinifera, focusing on fruit-transcriptome and metabolome analyses as leading approaches to understand berry physiology, secondary metabolism, and quality. Moreover, we show how omics data can be integrated in a simple format and offered to the research community as a web resource, giving the chance to inspect potential gene-to-gene and gene-to-metabolite relationships that can later be tested in hypothesis-driven research. In the frame of the activities promoted by the COST Action CA17111 INTEGRAPE, we present the first grapevine transcriptomic and metabolomic integrated database (TransMetaDb) developed within the Vitis Visualization (VitViz) platform (https://tomsbiolab.com/vitviz). This tool also enables the user to conduct and explore meta-analyses utilizing different experiments, therefore hopefully motivating the community to generate Findable, Accessible, Interoperable and Reusable (F.A.I.R.) data to be included in the future.

A Multidisciplinary Fingerprinting Approach for Authenticity and Geographical Traceability of Portuguese Wines

The interest in developing reliable wine authenticity schemes is a hot-topic, especially for wines with recognized added-value. In order to accomplish this goal, two dimensions need to be considered: the grapevine variety determination and the geographical provenance. The aim of this study was to develop a multidisciplinary approach applicable to wines from the sub region Melgaço and Monção of the demarcated Vinho Verde region and from the demarcated Douro region. The proposed scheme consists on the use of DNA-based assays to detect Single Nucleotide Polymorphisms (SNPs) on three genes of the anthocyanin pathway (UFGT, F3H and LDOX) coupled with High-resolution melting (HRM) analysis aiming the varietal identification. The Alvarinho wines revealed to have the same haplotype using this marker set, demonstrating its applicability for genetic identification. In addition, to assess their geographical provenance, a multi-elemental approach using Sr and Pb isotopic ratios of wine, soil and bedrock samples was used. The isotopic data suggest a relation between Sr and Pb uptake by vine roots and soil's texture and clay content, rather than with the whole rock's isotopic ratios, but also highlights the potential of a discriminating method based on the combination of selected isotopic signatures.

Ionomic variation in leaves of 819 plant species growing in the botanical garden of Hokkaido University, Japan

Ionomics is the measurement of total metal, metalloid, and nonmetal accumulation in living organisms. Plant ionomics has been applied to various types of research in the last decade. It has been reported that the ionome of a plant is strongly affected by its evolution and by environmental factors. In this study, we analyzed the concentration of 23 elements in leaves of 819 plant species (175 families) growing in the Botanic Garden of Hokkaido University, Japan. Relative variation estimated by the coefficient of variation in foliar concentrations of essential elements among various plant species tended to be low, whereas nickel concentration showed exceptionally large relative variation. By contrast, the relative variation in nonessential elements was high, particularly in sodium, aluminum, and arsenic. The higher relative variations in these element concentrations can be explained by the occurrence of plants that are hyperaccumulators for these elements. Differences in life forms such as herbaceous/woody species, deciduous/evergreen woody species and annual/perennial herbaceous species affected the concentration of several elements in the leaves. These differences were considered to be due to the combined factors including differences in lifespan, growth rate, and cell wall thickness of the leaves. Results of principal component analyses (based on concentration data of essential and nonessential elements in leaf samples) indicated phylogenetic influences on plant ionomes at the family level in Polypodiales, Pinales, Poales, and Ericales. Furthermore, when analyzing correlations among concentrations of all elements in each order and comparing among different orders, the results also suggested that Polypodiales, Pinales, and Poales each had a specific ion homeostasis network.

Geographical origin of Vitis vinifera cv. Cannonau established by the index of bioaccumulation and translocation coefficients

Geochemical fingerprints in grape require an identification of major and trace elements that show correlations between concentrations in soil and in plant tissues: these correlations are relevant to discriminate grapes according to geographical origin. The Vitis vinifera cultivar Cannonau is used to produce the renowned Italian controlled designation of origin (DOC) wine "Cannonau" from Sardinia. Two Cannonau vineyards located in Sardinia Region were studied to establish the relationship between geochemical features of vineyard soil and chemical composition of leaves and grape berries. Major and trace elements were determined by X-ray fluorescence and inductively coupled plasma-mass spectrometry in soil, leaf, and grape berry samples. The index of bioaccumulation and the translocation coefficients were also calculated for all elements. Data from the two study areas were compared by a non-parametric test and multivariate statistics (principal component analysis). The results showed a specific assimilation of these elements in leaf and grape berry from vine in two different soils. Moreover, geochemical characterization and statistical analysis enabled to discriminate the cultivar "Cannonau" according to geographical origin. The results showed that the elements that could establish a reliable correlation between the soil vineyard and leaves and grape berries from the two study areas were B, Sr, and Zr. These elements may therefore be used as geochemical fingerprints to identify the geographic origin of V. vinifera cv. Cannonau in the two study areas.

Rootstock effects on scion phenotypes in a 'Chambourcin' experimental vineyard

Understanding how root systems modulate shoot system phenotypes is a fundamental question in plant biology and will be useful in developing resilient agricultural crops. Grafting is a common horticultural practice that joins the roots (rootstock) of one plant to the shoot (scion) of another, providing an excellent method for investigating how these two organ systems affect each other. In this study, we used the French-American hybrid grapevine 'Chambourcin' (Vitis L.) as a model to explore the rootstock-scion relationship. We examined leaf shape, ion concentrations, and gene expression in 'Chambourcin' grown ungrafted as well as grafted to three different rootstocks ('SO4', '1103P' and '3309C') across 2 years and three different irrigation treatments. We found that a significant amount of the variation in leaf shape could be explained by the interaction between rootstock and irrigation. For ion concentrations, the primary source of variation identified was the position of a leaf in a shoot, although rootstock and rootstock by irrigation interaction also explained a significant amount of variation for most ions. Lastly, we found rootstock-specific patterns of gene expression in grafted plants when compared to ungrafted vines. Thus, our work reveals the subtle and complex effect of grafting on 'Chambourcin' leaf morphology, ionomics, and gene expression.

Greek Graviera Cheese Assessment through Elemental Metabolomics-Implications for Authentication, Safety and Nutrition

This study presents the comprehensive elemental profile of Greek Graviera (Gruyère) cheeses. In total, 105 samples from nine different geographic regions produced from sheep, goat and cow milk and their mixtures were assessed. Elemental signatures of 61 elements were investigated for determination of geographic origin and milk type. Regional and milk type classification through Linear Discriminant Analysis was successful for almost all cases, while a less optimistic cross validation exercise presented lower classification rates. That points to further research using a much larger sample set, increasing confidence for cheese authentication utilizing also bioinformatics tools under development. This is the first study reporting signatures of 61 elements in dairy products including all sixteen rare earth elements and all seven precious metals. Safety and quality were assessed regarding toxic and nutritive elements. According to both EU and USA regulations and directives, Graviera is a nutritional source for trace and macro elements with low levels of toxic elements.

Geochemical caper fingerprints as a tool for geographical origin identification

The identification of geographical origin of food products is important for both consumers and producers to ensure quality and avoid label falsifications. The caper plant (Capparis spinosa L., Brassicales Capparidaceae), a xerophytic shrub common in the Mediterranean area, produces buds and fruits that are commercialized in brine at high price. Those grown in Italy in the Aeolian Islands are renowned for their high quality. This study is aimed to establish a correlation between the geological and geochemical features of soil and the chemical composition of caper buds grown in two Aeolian Islands, Lipari and Salina. Major and trace elements were investigated by X-ray fluorescence and inductively coupled plasma-mass spectrometry in soil and caper samples from three localities in Lipari and Salina, and data from the three sites were compared by a nonparametric test, a correlation test and multivariate statistics (principal component analysis). The results allowed to discriminate soils according to geolithological characteristics of each area and detect a statistically significant correspondence between soil and caper samples for the elements Co, Fe, Mg and Rb, identifying thus possible geochemical caper fingerprints of origin. These results may also be useful to protect the high quality of Aeolian caper products by a suitable "Made in Italy" trademark and avoid falsifications and frauds.

Geochemical fingerprints of "Prosecco" wine based on major and trace elements

The terroir can be defined as interactive ecosystem that includes climate, geology, soil and grapevine, and it is used to explain the hierarchy of high quality of wine. In order to understand the terroir functions, it is necessary to analyse the interactions among the geology, soil and wine. To define a geochemical fingerprint, the relationship between geochemistry of vineyard soil and chemical composition of wine from Veneto Italian Region was studied. The vineyards tested belonged to four distinct wineries located in the Veneto alluvial plain, included in the Controlled Designation of Origin (DOC) area of Prosecco. We investigated the relationship between major and trace elements in soil and their concentrations in Prosecco wine according to geographical origin. The detection of chemical composition in soil and wine were analysed by inductively coupled plasma mass spectrometry, and data were elaborated by nonparametric test and multivariate statistics Linear Discrimination Analysis. The geochemical and statistical analyses allowed to discriminate the vineyard soils according to geo-lithological characteristics of each area and to identify the geochemical "Prosecco" fingerprints, useful against fraudulent use of DOC wine labels.