Correction to: SNP genotyping elucidates the genetic diversity of Magna Graecia grapevine germplasm and its historical origin and dissemination.

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SNP genotyping elucidates the genetic diversity of Magna Graecia grapevine germplasm and its historical origin and dissemination.

BACKGROUND: Magna Graecia is the ancient name for the modern geopolitical region of South Italy extensively populated by Greek colonizers, shown by archeological and historical evidence to be the oldest wine growing region of Italy, crucial for the spread of specialized viticulture around Mediterranean shores. Here, the genetic diversity of Magna Graecia grape germplasm was assessed and its role in grapevine propagation around the Mediterranean basin was underlined. RESULTS: A large collection of grapevines from Magna Graecia was compared with germplasm from Georgia to the Iberian Peninsula using the 18 K SNP array. A high level of genetic diversity of the analyzed germplasm was determined; clustering, structure analysis and DAPC (Discriminant Analysis of Principal Components) highlighted the genetic relationships among genotypes from South Italy and the Eastern Mediterranean (Greece). Gene flow from east (Georgia) to west (Iberian Peninsula) was identified throughout the large number of detected admixed samples. Pedigree analysis showed a complex and well-structured network of first degree relationships, where the cultivars from Magna Graecia were mainly involved. CONCLUSIONS: This study provided evidence that Magna Graecia germplasm was shaped by historical events that occurred in the area due to the robust link between South Italian and Greek genotypes, as well as, by the availability of different thermal resources for cultivars growing in such different winegrowing areas. The uniqueness of this ampelographic platform was mainly an outcome of complex natural or human-driven crosses involving elite cultivars.

Classification of wine grape biotypes according to their variety and sanitary condition by fingerprinting untargeted analysis.

Grapes secondary metabolites content mainly depends on variety, but also on climate and cultural conditions, including sanitary status. This study aimed to use a metabolomic fingerprinting approach for grouping 72 wine grape biotypes, Negro amaro n. (N), Malvasia nera di Brindisi/Lecce n. (M), and Uva di Troia n. (U), on the basis of their cultivar and virological conditions. The skins were extracted and analysed by flow injection mass spectrometry; a one-way ANOVA/Principal Component Analysis (PCA) allowed to efficiently cluster the samples, recognizing M from N and U biotypes. Conversely, the clusterisation of the biotypes affected by different virus complexes was really more tough and a clear distinction among infected plants was not always observed. However, very interestingly, by applying ANOVA/PCA to the biotypes of each varieties, singularly, healthy biotypes were sharply separated in all the varieties and a relationship between anthocyanin compounds and Grapevine leafroll associated virus (GLRaV3) slightly appeared.

Effect of pre-harvest inactivated yeast treatment on the anthocyanin content and quality of table grapes.

Due to the global warming, more and more often the red-pink grape varieties grown in the Mediterranean basin reveal an insufficient accumulation of anthocyanins and thus a scarce coloration. Nowadays, this is becoming an important technological issue, which may result in the reduction of the fresh market value of table grape. This study aimed at assessing the effect of the pre-harvest treatment by specific inactivated yeasts (YE) on the qualitative parameters and anthocyanin pattern of three red table grape varieties, which typically present poor and/or incomplete coloration during warm years. An increment of anthocyanins level up to almost seven folds corresponding to an improvement of red skin appearance was observed in all the treated table grapes, which was preserved after cold storage, too. While, no significant influence on chemical composition and berry texture and dimensions was found, meaning that YE did not cause appreciable taste changes in grapes.

Effect of two exogenous plant growth regulators on the color and quality parameters of seedless table grape berries.

Some red-pink table grape varieties, cultivated in warm climates, can fail in achieving the right level of anthocyanins responsible for the intense and uniform red color of berries. Nowadays, this is becoming an important technological issue in the Mediterranean area, which may result in decreasing market acceptance and potential economic value of table grape. Usually, plant growth regulators or phytohormones, such as S-ABA, can overcome this problem because they drive the accumulation of anthocyanins over the ripening season. Harpin proteins (HrP), which enhance the plant disease resistance, may be supposed to stimulate the anthocyanins biosynthesis in grape skin if applied close to veraison. Therefore, this research aimed at comparing the effect of HrP and S-ABA over the anthocyanin and color improvement of Crimson Seedless table grape grown in Southern Italy. For the first time, the exogenous treatment with HrP showed as effective as the less sustainable S-ABA one in favoring the anthocyanin accumulation, leading to peonidin-3-O-glucoside, cyanidin-3-O-glucoside, and malvidin-3-O-glucoside values up to 4 folds higher than control grapes and giving rise to a greater concentration of the more stable acylated anthocyanins. Overall, the color of berries was improved but keeping high the other quality characteristics.

Evidences for an alternative genealogy of 'Sangiovese'.

Two different hypothesis for the parentage of 'Sangiovese', the most important and widespread Italian winegrape, have been proposed by some previous studies. We screened our grapevine collection, mostly comprising south Italian cultivars collected to preserve biodiversity, to asses kinships. Surprisingly we found two previously unreported candidate parents for 'Sangiovese'. The first putative parent is 'Ciliegiolo' a well know variety already addressed as relative of 'Sangiovese'; the second putative parent is 'Negrodolce', an old local variety we recovered and was considered lost during the last century. In order to obtain a stronger statistical support for this new kinship, we tested seventy different microsatellite markers but only 57 were found reliable. The new proposed parentage stood well even with such a in depth molecular analysis whereas only one discrepancy was found in one of the 57 microsatellite marker analyzed. This discrepancy is certainly due to a null-allele and therefore it should not impair our hypothesis but it points out limits of the microsatellites profiling as a pedigree research method considering that this is the third different kinship proposed so far for 'Sangiovese'. Thus in this article, by means of detailed molecular fingerprinting, we provide a completely new strong evidence for a south Italian origin of 'Sangiovese' and we discuss our findings comparing our data with those previously reported by other authors.

Sangiovese and its offspring in southern Italy.

This paper demonstrates the importance of different approaches such as ampelography, historical researches, and molecular analysis to reveal direct parent-child relationship. The aim of this paper was to highlight the degree of relationship to five varieties spread in southern Italy, through ampelographic and molecular characterization: Sangiovese, Mantonico di Bianco, Gaglioppo di Cirò, Mantonicone, and Nerello Mascalese. Molecular characterization was carried out through 52 SSR molecular markers, showing that Sangiovese and Mantonico di Bianco are the parents of Gaglioppo di Cirò, Mantonicone, and Nerello Mascalese. Ampelographic description was performed using the method developed by the Organisation Internationale de la Vigne et du Vin. This analysis identifies three distinct groups: the first brings together Sangiovese and the two offspring Nerello Mascalese and Gaglioppo di Cirò, while Mantonico di Bianco and Mantonicone are positioned at a distance from the first and between them. Using molecular characterization, supported by the ampelographic one, we showed that Gaglioppo di Cirò, Mantonicone, and Nerello Mascalese, three varieties recovered in the southern regions of Italy, such as Calabria and Sicily, originated by the cross between a nationally spread grape variety as Sangiovese and a Calabria autochthonous vine as Mantonico di Bianco.

Validation assay of p3_VvAGL11 marker in a wide range of genetic background for early selection of stenospermocarpy in Vitis vinifera L.

DNA markers technology, derived from research in molecular biology and genomics, offers great promise for plant breeding, allowing the "molecular breeding" via marker-assisted selection. Grapevine genomic resources allowed, in recent years, the characterization at molecular level of genes involved in interesting phenotypes such as stenospermocarpic seedlessness, a trait really appreciated by consumers. Recent studies in table grapes revealed that the VvAGL11 gene, member of the D-lineage MADS-box family, controls the ovule identity, and thus potentially playing an important role in stenospermocarpy. Intragenic markers of VvAGL11 have been found and tested for breeding purposes. In the present paper, we describe an in deep assay on a total of 475 genotypes derived by our own grape germplasm and seeded × seedless crosses F1 offspring, to evaluate and verify the "diagnostic" power of VvAGL11 in marker-assisted selection. We found only 8/475 that were seeded and carried the seedless-associated allele in the STS p3_VvAGL11. However, and most importantly, there were no seedless varieties without such allele. We validated the marker as a 100 % effective tool for early negative selection of stenospermocarpy in Vitis vinifera L. crosses.