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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.

Tomato landraces, originated by adaptive responses to local habitats, are considered a valuable resource for many traits of agronomic interest, including fruit nutritional quality. Primary and secondary metabolites are essential determinants of fruit organoleptic quality, and some of them, such as carotenoids and phenolics, have been associated with beneficial proprieties for human health. Landraces' fruit taste and flavour are often preferred by consumers compared to the commercial varieties' ones. In an autumn-winter greenhouse hydroponic experiment, the response of three Southern-Italy tomato landraces (Ciettaicale, Linosa and Corleone) and one commercial cultivar (UC-82B) to different concentrations of sodium chloride (0 mM, 60 mM or 120 mM NaCl) were evaluated. At harvest, no losses in marketable yield were noticed in any of the tested genotypes. However, under salt stress, fresh fruit yield as well as fruit calcium concentration were higher affected in the commercial cultivar than in the landraces. Furthermore, UC-82B showed a trend of decreasing lycopene and total antioxidant capacity with increasing salt concentration, whereas no changes in these parameters were observed in the landraces under 60 mM NaCl. Landraces under 120 mM NaCl accumulated more fructose and glucose in the fruits, while salt did not affect hexoses levels in UC-82B. Ultra-performance liquid chromatography-tandem mass spectrometry analysis revealed differential accumulation of glycoalkaloids, phenolic acids, flavonoids and their derivatives in the fruits of all genotypes under stress. Overall, the investigated Italian landraces showed a different behaviour compared to the commercial variety UC-82B under moderate salinity stress, showing a tolerable compromise between yield and quality attributes. Our results point to the feasible use of tomato landraces as a target to select interesting genetic traits to improve fruit quality under stress conditions.

Tomato (Solanum lycopersicum L.) is a high value horticultural crop and an important dietary source of nutrients, vitamins and antioxidants. The cultivation is often subjected to drought, salinity and N-limited conditions. Thus, understanding the responses of tomato to salt and low N conditions will be instrumental to improve yields in stress-prone environments. In this study, physiological and molecular responses of three Italian landraces (TRPO0040, TRPA0130 and TRPO0670) to salt stress and low nitrate, alone or in combination were analysed. The experimental set up allowed four different treatments named: Control (13.5 mM NO3- - 0 mM NaCl), Salt stress (13.5 mM NO3- - 80 mM NaCl), N stress (3.4 mM NO3-- 0 mM NaCl) and Combined stress (3.4 mM NO3- - 80 mM NaCl). The treatments had different effects on plants: low N caused chlorosis, while salt stress inhibited growth causing loss of basal leaves. Leaf relative water content was affected by both salt and low nitrate, depending on the genotype, while proline content was dramatically increased by salt stress but not under combined stress. Growth parameters and fruit yield were reduced by single stress condition, and the highest reduction was observed in the combined stress. TRPO0040 genotype showed high Nitrogen Use Efficiency and Nitrogen Utilization Efficiency under salt, indicating that nitrogen allocation to fruits was not affected by this stress. We evaluated the impact of single and combined stresses on tomato transcriptome by performing RNAseq on roots and leaves of TRPO0040 after long-term exposure to the treatments. In leaves, a more extensive transcriptome reorganization was observed in response to N stress, while salt induced a significant variation in gene expression of a handful of genes. Parallel to the proline levels, expression of P5CS gene, encoding the rate limiting proline biosynthetic enzyme, was induced by salt, while the catabolic proline dehydrogenase was suppressed. Similarly, several genes encoding nitrate transporters were induced in N stress, including NRT2;2 and others. By contrast, in roots several thousands of differentially expressed genes (DEGs) DEGs in salt stress and only few hundreds in N stress were identified. Consistent with results gathered in Arabidopsis, SLAH1, a gene encoding a root specific anion transporter involved in the long distance transport of MOLECULAR MECHANISMS UNDERLYING MORPHO- PHYSIOLOGICAL ADAPTATION TO COMBINED SALT/LOW NUTRIENT STRESS IN TOMATO chloride ions, was upregulated in roots in salt stress condition, while a NRT2;4 like and AMT1 were induced by low nitrate. In the combined stress, a more extensive overlap of the DEGs was observed with the N stress rather than the salt stress for both roots and leaves. This indicates that nutrient availability may have a higher and longer- term impact on gene expression, compared to salt stress, which may induce rapid and transient responses, attenuated, particularly in leaves, when plant adaptation occurs. Altogether, we show that different cultivation regimes affect metabolic and transcriptomic profiles as well as growth in tomato, identifying a set of physiological and molecular targets specifically influenced by single or combined stress.

Background and Aims: Grapevine (Vitis vinifera L.) is one of the earliest domesticated crops, dating back 6000 years ago in the Near East before spreading into Europe. Despite the abundance of historical, archaeological and genetic records, until now secondary domestication events in European regions are not well demonstrated. Here, a genetic characterisation of grape germplasm from Calabria in Southern Italy, a crucial area of the Mediterranean Basin, aims to validate this area as a secondary centre of crop domestication. Methods and Results: True-to-type cultivar classification of 72 accessions was carried out by using microsatellite loci (simple sequence repeat) along with the main Organisation Internationale de la Vigne et du Vin ampelographic descriptors. The classification highlighted a high level of genetic diversity (He = 0.83) among native cultivars from Calabria. A decay of genetic diversity moving from southern Italy to north-western Mediterranean regions was observed, probably because of repeated founder effects during the grapevine expansion from the Mediterranean Basin to Europe. Single nucleotide polymorphism analysis showed an admixture genetic structure at K = 7, clarifying a complex network of pedigree relationships generated by crosses among cultivars. Parentage analysis underlined a high proportion of parent-offspring relationships (76%) in Mantonico Bianco and Pecorello, hypothesising their key role in the pedigree of many native cultivars from the southern Mediterranean area. Conclusion: Overall, our results appear to indicate a pivotal role of cultivars from Calabria in the grape genetic diversity of southern Italy. Furthermore, genetic analysis of grape wild accessions from Calabria should be of value in a discussion of a secondary centre of grape domestication. Significance of the Study: A large grape collection from Calabria was for the first time characterised through ampelographic and genetic analysis.

Increased interest towards traditional tomato varieties is fuelled by the need to rescue desirable organoleptic traits and to improve the quality of fresh and processed tomatoes in the market. In addition, the phenotypic and genetic variation preserved in tomato landraces represents a means to understand the genetic basis of traits related to health and organoleptic aspects and to breed them in modern varieties. In the frame of Horizon 2020, the TRADITOM project "Traditional tomato varieties and cultural practices: a case for agricultural diversification with impact on food security and health of European population" (http://traditom.eu/) aims to the collection, characterization and valorisation of European traditional tomato germplasm. The project has the long-term objective to understand biochemical and molecular factors underlying the typicality of traditional tomatoes, in the perspective to genetically improve them without losing quality traits and to eventually breed quality alleles into modern genetic backgrounds. As a part of the whole project collection of over 1500 accessions, this presentation describes the characterization of the main collections preserved in Italy, listing a total of over 430 samples. In two different phenotypic trials, the material has been scored for 18 qualitative variables and measured for further eight plant and fruit traits. Image analysis was conducted with the Tomato Analyzer software allowing for 15 morphometric and nine colorimetric parameters to be detected. A subset of the collection was subjected to metabolic profiling. The accessions showed a wide variability for most scored traits, including, for example, a 90-fold variation for fruit weight, 8-fold for locule number and >4-fold for the soluble solid and carotenoid content. Correlation and ANOVA statistics indicated distinctive differences among groups of accessions belonging to recognized typologies. The classification based on morphology was compared with genotypic data collected through 'genotyping by sequencing'.

Tomato (Solanum lycopersicum L.) is an important horticultural crop and a significant source of antioxidants in our diet. Yields suffer losses due to environmental stresses, including drought and salinity, which are among the most significant challenges for the future of global food production. Reduction of fertilizer inputs, including nitrate is also a priority in plant research, and it is aimed at minimizing pollution caused by agricultural activities, while obtaining fruits of high quality and long storability. In this study, we analysed vegetative and molecular responses of three tomato landraces (TRPO0040, TRPA0130 and TRPO0670) challenged with salt stress and low nitrate, alone or in combination, and their effects on fruit yield, quality and storability. The experiment was setup in a closed soilless system, in greenhouse, using four different conditions: N1S0: 13.5 mM NO3- - 0 mM NaCl; N1S1: 13.5 mM NO3- - 80 mM NaCl; N0S0: 3.4 mM NO3-- 0 mM NaCl; N0S1: 3.4 mM NO3- - 80 mM NaCl. Several parameters were monitored during the vegetative phase, including stomatal conductance, leaf relative water and proline content, expression of selected ion transporter genes. Relative water content was affected by both salt and nitrate concentration, while proline content was dramatically increased by salt stress in high nitrate condition only. Growth parameters as well as fruit yield were reduced in the presence of stress, with the highest reduction observed in plants exposed to the combined stress. Highest yields were obtained in N1S0, however fruits harvested from low nutrient-treated plants were virtually all marketable, regardless the presence of NaCl. Soluble solids content was highly affected by salt, as expected. The cultivation regime also affected fruit shelf life of the three genotypes over the 90-day period monitored. High salt in the nutrient solution improved fruit shelf life regardless of genotype and nitrate concentration. In the absence of NaCl, NO3- supply in the nutrient solution did not affect fruit shelf life in TRPO0670 and TRPA0130, while TRPO0040 fruits showed an extended shelf life at low nitrate compared to high nitrate supply. Fruit firmness and weight declined in all genotypes and treatments during post-harvest; hence, they were not ?? RUGGIERO A.*, BATELLI G.*, VENEZIA A. ??NURCATO R.*, COSTA A.*, ?? discriminating parameters between treatments. Nitrogen Use Efficiency (NUE) evaluation in all treatments and landraces revealed that TRPO0040 maintained high NUE under salt stress, indicating that N allocation to fruits was not inhibited by salt in this genotype. Altogether, we have verified that different cultivation regimes affect fruit shelf life and quality in tomato, and identified a set of vegetative parameters specifically influenced by single or combined stress. In addition, RNAseq and qRT-PCRs analyses are being pursued in order to get further insights into the molecular basis of fruit shelf life under different cultivation regimes.

Tomato (Solanum lycopersicum L.) shows a noteworthy morphological diversification in different geographical regions. Particularly, Italy and Spain have been recognized as secondary centres of diversification being tomato cultivation characterized by a wealth of landraces with different fruit sizes and shapes. Among the germplasm collections, long shelf-life (LSL) tomatoes typical of the Mediterranean region, the so-called tomato 'da serbo', form a group of drought tolerant landraces that can grow without irrigation. The mutant phenotype is characterized by small round tomatoes with excellent nutritional properties due to the elevated concentration of sugars and antioxidant substances. The valorisation of this ancient tomato germplasm is important to extend the genetic basis of the tomato genome and to limit the genetic erosion caused by the employment of modern cultivars, thus conserving an important source of biodiversity. The present study provided a Genome-Wide Association Study using an important LSL tomato collection from south Italy and Spain, in order to identify SNPs associated to genome of the analysed collection. Genome-wide SNP genotyping was performed using the Infinium assay that was developed by the Solanaceae Coordinated Agricultural Project (SolCAP). The data obtained from the assays were analysed using the Genotyping Module of the GenomeStudio software (Illumina Inc.). The SNP dataset was accurately inspected and properly modified according to the following criteria: i) samples with low SNP call quality (p50GC

Genetic diversity among 70 "scarlet eggplant" (Solanum aethiopicum L.) entries from different geographical origins was assessed. Entries were firstly evaluated for the main morphologic traits and chlorogenic acid content. Standard statistics and multivariate analyses were utilized to assess the phenotypic diversity and grouping the entries. In addition, amplified fragment length polymorphism (AFLP) and simple sequence repeat (SSR) analyses were used to evaluate genetic relationships among entries. Differences between entries are highly significant for all descriptors. Principal component analysis (PCA) revealed that the first three components accounted for 74% of the total variance. Morphologic traits were associated with the first two components, while the third one was moderately correlated with the chlorogenic acid content. The observed similarity allowed identifying only three main groupings. The clusters obtained did not show any relationships with geographic origins and/or botanical groups. Matrices of genetic similarity from AFLP and SSR data were utilized in order to obtain a dendrogram. A large cluster included several entries from South America with limited rate of genetic variation was observed. On the contrary, higher amount of variation was observed in the cluster with entries from Africa, in which are also present in the accessions collected in Italy. These entries appeared always morphologically and genetically distinguishable from the others. These results provided additional information for the conservation, improvement and legal protection of the ecotype 'melanzana rossa di Rotonda', cultivated in Italy.