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Abstract: BACKGROUND: Cultivated pepper is a rich source of diverse bioactive compounds with potential properties related to the prevention of major degenerative and proliferative diseases. In the present study, 15 sweet pepper varieties, highly appreciated on the Italian market, were assessed for variation in the content of ascorbic acid, isoprenoids and flavonoids, as well as morpho‐agronomic performances and molecular diversity. RESULTS: The collection under study showed a wide variability for all traits considered. Traditional cultivars, although less productive, were characterized by a high content of β‐carotene and ascorbic acid, reaching maximum concentrations of 230.5 mg kg–1 fresh weight (fw) and 2750 mg kg–1 fw, respectively. Strong correlations were demonstrated between neoxanthin and luteolins. Fruit weight was positively correlated with α‐tocopherol content and negatively correlated with luteolins content. The genotyping by sequencing platform allowed the identification of 1833 single nucleotide polymorphism, which better defined the relationships among cultivars, based on provenance and improvement rate. CONCLUSIONS: The present study provides an overview of the variability in the expression of fruit nutritional traits in a collection of horn‐shaped pepper cultivars, integrating agronomic and molecular data. The impact for breeding and consumers is discussed. © 2017 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

In eukaryotic cells, the non-proteinogenic amino acid ornithine is the precursor of arginine and polyamines (PAs). The final step of ornithine biosynthesis occurs in plants via a cyclic pathway catalyzed by N2-acetylornithine:N-acetylglutamate acetyltransferase (NAOGAcT). An alternative route for ornithine formation, the linear pathway, has been reported for enteric bacteria and a few other organisms; the acetyl group of N2-acetylornithine is released as acetate by N2-acetylornithine deacetylase (NAOD). NAOD activity has never been demonstrated in plants, although many putative NAOD-like genes have been identified. In this investigation, we examined the effect of down-regulation of the putative Arabidopsis thaliana NAOD gene by using AtNAOD-silenced (sil#17) and T-DNA insertional mutant (atnaod) plants. The ornithine content was consistently reduced in sil#17 and atnaod plants compared with wild-type plants, suggesting that in addition to NAOGAcT action, AtNAOD contributes to the regulation of ornithine levels in plant cells. Ornithine depletion was associated with altered levels of putrescine and spermine. Reduced AtNAOD expression resulted in alterations at the reproductive level, causing early flowering and impaired fruit setting. In this regard, the highest level of AtNAOD expression was observed in unfertilized ovules. Our findings suggest that AtNAOD acts as a positive regulator of fruit setting and agree with those obtained in tomato auxin-synthesizing parthenocarpic plants, where induction of SlNAOD was associated with the onset of ovary growth. Thus, here we have uncovered the first hints of the functions of AtNAOD by connecting its role in flower and fruit development with the regulation of ornithine and PA levels. [ABSTRACT FROM AUTHOR]

Gene exchanges between Solanum melongena and its allied relative Solanum aethiopicum are a crucial prerequisite for introgression of useful traits from the allied species into the cultivated eggplant. In order to evaluate the extent of genetic recombination between the 2 species, biochemical and molecular markers were employed. A dihaploid population obtained through anther culture of the corresponding tetraploid somatic hybrids was genetically analyzed. The extent of disomic/ tetrasomic inheritance and segregation ratios of 3 isozyme systems and intersimple sequence repeat (ISSR) markers were evaluated. The dihaploids, being derived from microspores, allowed for simple, complete, and accurate analyses. The segregation of 280 ISSR markers (110 aethiopicum-specific, 104 melongena -specific, and 66 monomorphic) were evaluated in 71 dihaploids. According to the genetic constitution (simplex/duplex/triplex), almost 64% of the fragments revealed the tetrasomic and/or disomic inheritance. With regard to the assigned species-specific fragments, 68% and 4% were unambiguously the result of tetrasomic and disomic inheritance, respectively. Twenty-four of the 66 monomorphic ISSRs were inherited according to random chromatid segregation. The phenotypes of glucose-6-phosphate dehydrogenase (G-6 -PDH), 6-phosphogluconate dehydrogenase (6-PGDH), and shikimate dehydrogenase (SKDH) were studied in 70 dihaploids and inferences were made about the allelic state of their 5 loci. The isozyme markers segregated in the dihaploids in a distorted manner, their segregations did not fit in with any of the expected segregation ratios. However, tetrasomic inheritance might be suggested for G-6-PDH 2 and SKDH 1 loci. Our results demonstrated that gene exchanges occurred readily in the somatic hybrids between S. melongena and S. aethiopicum gr. Gilo. [ABSTRACT FROM AUTHOR]

Water-, salt-, alcohol- and alkali-soluble seed storage proteins, extracted from 21 “cipolla bianca di Pompei” landraces (Allium cepaL.), were analyzed by anionic exchange-high performance liquid chromatography (AE-HPLC). Chromatographic elution profiles (time range 0-40 min) at 280 nm of water-soluble seed proteins evidenced the presence of 21 peaks, which allowed all the landraces studied to be distinguished from each other. The differences detected were both qualitative (presence/absence of one or more peaks) and quantitative; the water-soluble proteins were useful in differentiating landraces and cultivars while the other seed protein fractions only showed a weak polymorphism. The cluster analysis, based on HPLC data, showed that the landraces clustered with a genetic similarity degree ranging between 69% and 94%. The possibility of discriminating among closely related onion landraces during the course of breeding programmes could allow the identification of biochemical markers linked to useful agronomical traits. As observed by chromatographic analysis, the globulin composition of onion water-soluble seed protein appears to be independent of environmental growth conditions. The biochemical characterization of the available typical onion germplasm may contribute to obtain a community recognition and denomination, such as Denomination of Protected Origin (D.O.P.), Indication of Protected Origin (I.G.P.) or Specificity Attestation (A.S.). The biochemical method here developed resulted of high resolution, cost-effective and time-saving for characterization and genetic purity assessment of the landraces studied. [ABSTRACT FROM AUTHOR]

Phaseolin (PHAS) and phytohemagglutinin (PHA) represent the main seed protein fractions in common bean. Currently, several ecotypes of common bean cultivated in marginal areas exist, above all in Southern Italy regions. Such germplasm could be lost due to the genetic uniformity of new cultivars. Moreover, the first step to obtain community recognition and denomination requires the full characterization of the available germplasm. In the present study, PHAS and PHA extracted in saline solutions from nine ecotypes of common bean `di Controne' (Campania region) were analysed by anionic and cation exchange-high performance liquid chromatography (AE- and CE-HPLC), SDS-PAGE and IEF. The results obtained by AE-HPLC have allowed us either to standardize a high resolution, cost-effective and time-saving biochemical methodology or to compare the studied ecotypes with some cultivars of common bean most widely grown in Italy. The elution profiles of the nine ecotypes, already analyzed at the morpho-physiological and molecular levels, allowed us to differentiate the ecotypes either from a qualitative point of view (presence/absence of one or more peaks) or a quantitative one. For instance, the ecotypes of common bean `di Controne' could be clearly differentiated from some commercial cultivars of dwarf and/or climbing bean. In contrast, the analysis of the electrophoresis patterns supplied less information. [ABSTRACT FROM AUTHOR]

In tomatoes, grafting onto resistant rootstocks represents an effective strategy to control several soil-borne diseases that reduce crop profitability, especially for landraces with little or no resistance to multiple pathogens/pests. In this study, the high-value 'Corbarino' tomato landrace was grafted onto seven commercial Solanum interspecific rootstocks to evaluate graft compatibility, yield performance, and qualitative characteristics under greenhouse healthy conditions. Three rootstocks were the most effective in improving fruit yield without negatively affecting the carpometric, technological, and health-related traits of the traditional tomato. 'Dinafort' rootstock increased fresh and dry yield, harvest index, and fruit/clusters, while mean fruit weight, shape index, total and soluble solid content, simple sugars, organic acids, flavonoids, ascorbic acid, and trans -lycopene content did not differ with respect to the ungrafted 'Corbarino'. 'Interpro' rootstock also showed promising results for the overall yield and quality traits, although it reduced the trans -lycopene content in the fruit. 'Silex' rootstock showed the highest harvest index as result of decreased vigour. The fruit quality induced by 'Silex' was satisfactory and high levels of simple sugars, flavonoids, ascorbic acid, and trans -lycopene were also observed. However, graft success, especially for 'Dinafort' and 'Silex', needs to be improved by investigating more suitable methods for seedling production, grafting, acclimatization, etc. [ABSTRACT FROM AUTHOR]

Arabidopsis thaliana At4g17830 codes for a protein showing sequence similarity with the Escherichia coli N-acetylornithine deacetylase (EcArgE), an enzyme implicated in the linear ornithine (Orn) biosynthetic pathway. In plants, Nacetylornithine deacetylase (NAOD) activity has yet to be demonstrated; however, At4g17830-silenced and mutant (atnaod) plants display an impaired reproductive phenotype and altered foliar levels of Orn and polyamines (PAs). Here, we showed the direct connection between At4g17830 function and Orn biosynthesis, demonstrating biochemically that At4g17830 codes for a NAOD. These results are the first experimental proof that Orn can be produced in Arabidopsis via a linear pathway. In this study, to identify the role of AtNAOD in reproductive organs, we carried out a transcriptomic analysis on atnaod mutant and wild-type flowers. In the atnaod mutant, the most relevant effects were the reduced expression of cysteine-rich peptidecoding genes, known to regulate male-female cross-talk during reproduction, and variation in the expression of genes involved in nitrogen:carbon (N:C) status. The atnaod mutant also exhibited increased levels of sucrose and altered sensitivity to glucose. We hypothesize that AtNAOD participates in Orn and PA homeostasis, contributing to maintain an optimal N:C balance during reproductive development. [ABSTRACT FROM AUTHOR]

Lectins, phytic acid and condensed tannins exert major antinutritional effects in common bean when grains are consumed as a staple food. In addition, phaseolin, i.e., the major storage protein of the bean seed, is marginally digested when introduced in the raw form. Our breeding target was to adjust the nutrient/antinutrient balance of the bean seed for obtaining a plant food with improved nutritional value for human consumption. In this study, the seeds of twelve phytohaemagglutinin-E-free bean lines carrying the mutations low phytic acid, phytohaemagglutinin-L-free, α-Amylase inhibitors-free, phaseolin-free, and reduced amount of condensed tannins, introgressed and differently combined in seven genetic groups, were analyzed for their nutrient composition. Inedited characteristics, such as a strong positive correlation (+0.839 **) between the genetic combination "Absence of phaseolin + Presence of the α-Amylase Inhibitors" and the amount of "accumulated iron and zinc", were detected. Three lines carrying this genetic combination showed a much higher iron content than the baseline (+22.4%) and one of them in particular, achieved high level (+29.1%; 91.37 µg g−1) without any specific breeding intervention. If confirmed by scientific verification, the association of these genetic traits might be usefully exploited for raising iron and zinc seed content in a bean biofortification breeding program. [ABSTRACT FROM AUTHOR]

Grafting of fruiting vegetables is an effective technique to overcome pests and diseases in modern cropping systems and it is often used to improve yield and fruit quality. Eggplant is an important vegetable crop that benefits significantly from grafting. In this regards, the exploitation, valorization and breeding of new rootstock genotypes as possible substitute to those commonly used ( Solanum torvum and tomato hybrids) would permit an intensive eggplant crop system in those situations where a rootstock rotation is required. In the present article, we study the effects of several potential rootstocks including both wild/allied species of eggplant [ S. torvum (STO), S. macrocarpon (SMA), S. aethiopicum (accession SASI), S. aethiopicum (accession SASa2), S. paniculatum (jurubeba) (SPA) and S. indicum (SIN)] and Msa 2/2 E7 and 460 CAL. eggplant hybrids on plant vigor, yield and fruit characteristics of eggplant F 1 hybrid (‘Birgah’), in two spring-summer growing seasons (2014 and 2015). SPA and the hybrids Msa 2/2 E7 and 460 CAL. displayed a high percentage of grafting success. ‘Birgah’ scion grafted onto the two above-mentioned rootstocks showed a notable vigour and yield. Both rootstocks did not promote any unfavorable effects on apparent fruit quality traits and overall fruit composition. Furthermore, the concentration of glycoalkaloids in the fruit remained below the recommended safety value (200 mg/100 g of dw). These results suggest that SPA and Msa 2/2 E7 and 460 CAL. eggplant hybrids might represent a potential rootstock alternative to S. torvum . [ABSTRACT FROM AUTHOR]

Landraces are an important resource for crop breeding, due to their resilience and content of quality traits. However, genetic and phenotypic variability needs to be carefully characterized for proper direct and indirect use. In the present study, a multidisciplinary approach was carried out to assess the Italian sweet pepper landrace ‘Friariello’. A total of 18 traditional accessions were compared with five hybrids and two ecotypes with similar fruit typology. Genetic and morpho-agronomic characterization allowed us to distinguish five different group types of ‘Friariello’. Accessions showing two/three lobes at the blossom end of the fruit were found to be the most productive, whereas the genotypes showing one/two lobes at the blossom end were the most homogeneous. A total of 167 volatile organic compounds (VOCs) were identified in the collection analysed. Moreover, of the 37 targeted VOCs, 29 showed significant differences in content among the pepper genotypes studied. Of such VOCs related to main flavours described for pepper in the literature, ten were found to be the major determinants of variability among the derived ‘Friariello’ groups. A slightly negative, albeit not significant, correlation was observed between ascorbic acid (AsA) content and agronomic traits, suggesting a better quality for less productive accessions, but also the possibility to improve yield without significantly reducing the AsA levels. The approach used allowed us to define how the different typologies can be used for different breeding purposes, integrating the peculiar properties in order to establish a desirable landrace ideotype. Furthermore, valuable sources for improving quality traits in pepper breeding were identified. [ABSTRACT FROM PUBLISHER]

Physico-chemical traits of three eggplant genotypes (“Tunisina”, “Buia” and “L 305”) were evaluated before and after two cooking treatments (grilling and boiling). Different genotypes revealed different changes after cooking, with “Tunisina” showing a better retention of phytochemicals with respect to other two genotypes. The main physical phenomena were water loss during grilling, and dry matter loss after boiling. Chlorogenic acid, the main phenolic in eggplant, resulted higher in grilled samples, while delphinidin glycosides resulted more retained in boiled samples. Glycoalkaloids, thiols and biogenic amines were generally stable, while 5-hydroxy-methyl-furfural was found only in grilled samples. Interestingly, Folin–Ciocalteu index and free radical scavenging capacity, measured with three different assays, were generally increased after cooking, with a greater formation of antioxidant substances in grilled samples. NMR relaxation experiments clarified the hypothesis about the changes of eggplant compounds in terms of decomposition of larger molecules and production of small ones after cooking. [ABSTRACT FROM AUTHOR]

Background: Genome Wide Association Studies (GWAS) have been recently used to dissect complex quantitative traits and identify candidate genes affecting phenotype variation of polygenic traits. In order to map loci controlling variation in tomato marketable and nutritional fruit traits, we used a collection of 96 cultivated genotypes, including Italian, Latin American, and other worldwide-spread landraces and varieties. Phenotyping was carried out by measuring ten quality traits and metabolites in red ripe fruits. In parallel, genotyping was carried out by using the Illumina Infinium SolCAP array, which allows data to be collected from 7,720 single nucleotide polymorphism (SNP) markers. Results: The Mixed Linear Model used to detect associations between markers and traits allowed population structure and relatedness to be evidenced within our collection, which have been taken into consideration for association analysis. GWAS identified 20 SNPs that were significantly associated with seven out of ten traits considered. In particular, our analysis revealed two markers associated with phenolic compounds, three with ascorbic acid, β-carotene and trans-lycopene, six with titratable acidity, and only one with pH and fresh weight. Co-localization of a group of associated loci with candidate genes/QTLs previously reported in other studies validated the approach. Moreover, 19 putative genes in linkage disequilibrium with markers were found. These genes might be involved in the biosynthetic pathways of the traits analyzed or might be implied in their transcriptional regulation. Finally, favourable allelic combinations between associated loci were identified that could be pyramided to obtain new improved genotypes. Conclusions: Our results led to the identification of promising candidate loci controlling fruit quality that, in the future, might be transferred into tomato genotypes by Marker Assisted Selection or genetic engineering, and highlighted that intraspecific variability might be still exploited for enhancing tomato fruit quality. [ABSTRACT FROM AUTHOR]

Tomato (Solanum lycopersicum L.) is one of the most important vegetable crops highly appreciated for the nutritional properties and content of beneficial compounds for human health. After its domestication, this crop has been spread throughout the world and found its secondary centre of diversification in the Mediterranean basin, where numerous landraces have been developed. Among these, 'San Marzano' is a famous and remunerative PDO variety for processing and fresh market consumption. 'Re Fiascone' is an ancient cultivar for which ongoing efforts aim to promote its diffusion and commercialisation. Both find their origin in the Campania region in Southern Italy where in the past decades, several accessions have been selected and handed down by farmers. This study reports a comprehensive assessment for morphological and biochemical traits of twenty-one accessions of the two landraces. Fruit morphology and content of sugars and flavonoids were the most discriminating parameters among cultivars. Among sugars and organic acids, fructose and citric acid were the most represented compounds, respectively. We found level of trans-lycopene and β-carotene up to 112.82 and 16.29 µg g−1 of fresh product, respectively, while ascorbic acid levels reached values up to 22.48 mg 100 g−1 of fresh weight. Molecular analysis has been performed using a double approach for microsatellite genotyping based on capillary electrophoresis and high-resolution melting. Results highlighted a separation of the accessions according to 'Re Fiascone' and 'San Marzano' identifying both unique and admixed accessions between the two groups. The study approach aims at the recovery and valorisation of local genetic resources, but also at the identification of traits of interest to transfer in breeding programs. [ABSTRACT FROM AUTHOR]

[Display omitted] • Diversity study of Italian sweet pepper landraces over two years (Y). • Ascorbic acid, organic acids, and isoprenoids were greatly impacted by Y and G x Y. • 124 and 277 volatiles were detected during the 1st and the 2nd year, respectively. • Genomic markers revealed footprints based on origin and typology of landraces. • Geranylacetone, hexanal and linalool as the best candidates for the fruit-flavour. Twenty-eight sweet pepper (C. annuum L.) landraces were grown for two consecutive seasons in a Mediterranean environment and evaluated for a wide range of volatile and non-volatile phytochemicals and agronomic performance parameters. A high genotypic (G) variance effect was found for flavonoids and sugars while vitamin C, organic acids and isoprenoids, showed a variable degree of G, years (Y), and G × Y interaction. Thirty-one targeted volatile organic compounds (VOCs) were found significantly different across varieties in both seasons. Combining targeted and untargeted profiling of VOCs revealed 124 and 277 compounds in the first and the second year, respectively. Fruit weight showed negative correlations with several phytochemical traits, whereas soluble solids were strongly correlated to benzene acetaldehyde in charge of sweet and floral aroma. Genomic data based on 1421 single-nucleotide polymorphism reveal clusters based on origin and fruit type, highlighting factors that driven the selection of the studied landraces. [ABSTRACT FROM AUTHOR]

Background: Parthenocarpic tomato lines transgenic for the DefH9-RI-iaaM gene have been cultivated under open field conditions to address some aspects of the equivalence of genetically modified (GM) fruit in comparison to controls (non-GM). Results: Under open field cultivation conditions, two tomato lines (UC 82) transgenic for the DefH9-RI-iaaM gene produced parthenocarpic fruits. DefH9-RI-iaaM fruits were either seedless or contained very few seeds. GM fruit quality, with the exception of a higher β-carotene level, did not show any difference, neither technological (colour, firmness, dry matter, °Brix, pH) nor chemical (titratable acidity, organic acids, lycopene, tomatine, total polyphenols and antioxidant capacity -TEAC), when compared to that of fruits from control line. Highly significant differences in quality traits exist between the tomato F1 commercial hybrid Allflesh and the three UC 82 genotypes tested, regardless of whether or not they are GM. Total yield per plant did not differ between GM and parental line UC 82. Fruit number was increased in GM lines, and GM fruit weight was decreased. Conclusion: The use in the diet of fruits from a new line or variety introduces much greater changes than the consumption of GM fruits in comparison to its genetic background. Parthenocarpic fruits, produced under open field conditions, contained 10-fold less seeds than control fruits. Thus parthenocarpy caused by DefH9-RI-iaaM gene represents also a tool for mitigating GM seeds dispersal in the environment. [ABSTRACT FROM AUTHOR]

Plants produce a huge array of secondary metabolites that play a key role in defense mechanisms against detrimental microorganisms and herbivores, and represent a suitable alternative to synthetic fungicides in sustainable agriculture. In this work, twelve crude hydroethanolic extracts derived from leaves of different potato cultivars were chemically characterized by LC/MS and their antioxidant properties were investigated in vitro. Furthermore, the biological activity against the fungal pathogen Rhizoctonia solani was evaluated both in vitro and in vivo. Extracts showed the ability to inhibit R. solani growth in vitro and significantly reduced damping-off incidence in in vivo experiments. Furthermore, R. solani mycelia exposed to the extracts showed an altered morphology (low translucency, irregular silhouette, and cytoplasmatic content coagulation) compared to the untreated control in light microscopy examination. Principal component analysis conducted on identified chemical compounds highlighted significant metabolic variations across the different extracts. In particular, those that inhibited most of the growth of the pathogen were found to be enriched in α-chaconine or α-solanine content, indicating that their biological activity is affected by the abundance of these metabolites. These results clearly indicated that plant-derived compounds represent a suitable alternative to chemicals and could lead to the development of new formulates for sustainable control of plant diseases. [ABSTRACT FROM AUTHOR]

Grafting is generally considered effective in ameliorating vegetable crop tolerance to biotic and abiotic stresses. The use of interspecific hybrid as rootstock for eggplant may represent a valid alternative approach to enhance eggplant performance. However, studies on the effects of different rootstocks on eggplant plant vigor, yield, and fruit quality traits often show conflicting results. Thus, an experiment was performed in two spring–summer growing seasons (2014 and 2015) by grafting eggplant ′Scarlatti′ F1 hybrid on two accessions of S. aethiopicum gr. gilo and on the interspecific hybrid S. melongena × S. aehtiopicum gr. gilo in comparison to the most common eggplant rootstock S. torvum. Results indicate that S. melongena × S. aethiopicum gr. gilo interspecific hybrid and S. torvum improved grafting success, plant vigor, early flowering and yield in ′Scarlatti′ F1 scion. All rootstocks tested did not negatively influence fruit apparent quality traits and fruit quality composition. Moreover, fruit glycoalkaloids content remained below the recommended threshold value. These findings suggest that the use of S. melongena × S. aethiopicum gr. gilo interspecific hybrid as rootstock may be a good alternative to the most commonly used S. torvum. [ABSTRACT FROM AUTHOR]