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BACKGROUND: The Bletilla genus of Orchidaceae includes plants with great economic value, among which B. striata is the main traditional medicinal plant, and its pseudobulb, known as BaiJi, was first recorded in Shennong's Classic of Materia Medica. However, there has been little systemic evaluation of the germplasm quality of Bletilla plants in China. In order to comprehensive evaluate the Bletilla resources in China and screen out the candidate phenotypic traits determining yield and/or quality of Bletilla, the variation of phenotypic indicators (pseudobulb, leaf, stem, inflorescence, flower) and active ingredients contents (polysaccharide, total phenolics and militarine) in different populations of B. striata and B. ochracea were investigated through 4 years' common-garden experiment. RESULTS: There were abundant phenotypic variations and significant differences among different populations in the morphological phenotypes, pseudobulb weight and main active ingredient contents. AHBZ, HBLT and HBSN populations showed good prospects for industrial development, presenting higher quality in terms of yield and main active ingredient content. Pseudobulb yield, polysaccharide and total phenol content are positively correlated with phenotypic traits. Militarine content is negatively correlated with almost all indexes. Plant height, leaf width and stem diameter may be important indicators of potential excellent germplasms. CONCLUSIONS: Bletilla is not strictly geoauthentic medicinal plants. B. ochracea could be accepted as an alternative resource to B. striata. The best harvest period of Bletilla is the third year after cultivation. Plant height, leaf width and stem diameter may be important indicators of potential excellent germplasms. These results provide important information required for the efficient screening and utilization of Bletilla germplasm resources. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12870-022-03540-w.

11 páginas, 6 tablas. ; Due to adaptation to new ecological and manmade conditions, the large diversity evolved in the European common bean germplasm is of particular interest for plant breeding. The knowledge of the genetic relationships within and among races and gene pools and their performance per se will provide bean breeders with a starting point in designing crosses using contrasting and complementary parents to broaden the genetic base within the different commercial classes. A genetic study of seed size variation and protein markers in progeny derived from 16 intraracial, interracial and inter-gene pools European common bean populations was conducted. General and specific combining ability (GCA and SCA) values were significant for seed weight, indicating that both additive and nonadditive genetic effects were involved in conditioning seed weight. Interracial populations showed transgressive values due to the accumulation of large-seeded alleles. Genetic variation inside Andean germplasm, and Chile and Peru races in particular, exhibited useful genetic progress in these populations, providing lines with a large seed size, and so, an excellent market potential. The distribution of incompatibility between both gene pools (Mesoamerican and Andean) of the common bean was explored. Inter-gene pool populations provided lower means of inbred segregants than the mid-parent value. Therefore, a good option it would be select for large seed size according to a recurrent or congruity inbred-backcrossing selection programs. Analysis of allele markers frequencies in inter-gene populations showed segregation distortion with a higher than expected frequency of alleles from the Mesoamerican gene pool, many of which were fixed in the F7 lines. The presence of a great percentage of markers that showed segregation distortion in these populations (87%) indicated that this phenomenon can be amplified by using distance related common bean genotypes. In addition, a high percentage of heterozygotes for the Phs locus (for the seed storage protein phaseolin) was found, which suggest that the Andean homozygous TT could not be expressed in Mesoamerican genetic background due to the action of some form of female specific mechanisms that affected gene exchange between parental germplasm in inter-gene pool populations. The present work provides useful information in the establishment of large seed size germplasm that could have a great deal of interest among breeders and may offer some possibilities to exploit existing variation within and between common bean races. ; Research was supported by the projects AGF97-0324 and AGL2005-01268/AGR from the Spanish Government, PGIDIT02RAG40301PR from the Galician Government (Spain), and EUFEDER Funds. A.M. González thanks her fellowship to Ministry of Education, Culture and Sports of Spain. ; Peer reviewed

Although a large number of single nucleotide polymorphism (SNP) markers covering the entire genome are needed to enable molecular breeding efforts such as genome wide association studies, fine mapping, genomic selection and marker-assisted selection in peach [Prunus persica (L.) Batsch] and related Prunus species, only a limited number of genetic markers, including simple sequence repeats (SSRs), have been available to date. To address this need, an international consortium (The International Peach SNP Consortium; IPSC) has pursued a coordinated effort to perform genome-scale SNP discovery in peach using next generation sequencing platforms to develop and characterize a high-throughput Illumina Infinium® SNP genotyping array platform. We performed whole genome re-sequencing of 56 peach breeding accessions using the Illumina and Roche/454 sequencing technologies. Polymorphism detection algorithms identified a total of 1,022,354 SNPs. Validation with the Illumina GoldenGate® assay was performed on a subset of the predicted SNPs, verifying ∼75% of genic (exonic and intronic) SNPs, whereas only about a third of intergenic SNPs were verified. Conservative filtering was applied to arrive at a set of 8,144 SNPs that were included on the IPSC peach SNP array v1, distributed over all eight peach chromosomes with an average spacing of 26.7 kb between SNPs. Use of this platform to screen a total of 709 accessions of peach in two separate evaluation panels identified a total of 6,869 (84.3%) polymorphic SNPs. The almost 7,000 SNPs verified as polymorphic through extensive empirical evaluation represent an excellent source of markers for future studies in genetic relatedness, genetic mapping, and dissecting the genetic architecture of complex agricultural traits. The IPSC peach SNP array v1 is commercially available and we expect that it will be used worldwide for genetic studies in peach and related stone fruit and nut species. ; This work was funded by: United States Department of Agriculture's National Institute of Food and Agriculture - Specialty Crop Research Initiative project (http://www.csrees.usda.gov/fo/specialtycropresearchinitiative.cfm), "RosBREED: Enabling marker-assisted breeding in Rosaceae" (Grant # 2009-51181-05808); Ministero delle Politiche Agricole Alimentari e Forestali -Italy (MiPAAF, http://www.politicheagricole.it) through the project "DRUPOMICS: Sequenziamento del genoma del pesco ed utilizzo della sequenza in programmi di miglioramento della qualità del frutto del pesco e della resistenza alle malattie" (Grant # DM14999/7303/08). European Union-funded project "FruitBreedomics: Integrated approach for increasing breeding efficiency in fruit tree crops" (Grant #FP7-265582; http://fruitbreedomics.com/; http://ec.europa.eu/research/fp7/index_en.cfm). AGL2009-07305 project and Consolider-Ingenio 2010 Program project (grant # CSD2007-00036) both funded by the Spanish Ministry of Science and Innovation (http://www.micinn.es/). ; Peer reviewed

[EN] Double digest restriction-site associated sequencing (ddRAD-seq) is a flexible and cost-effective strategy for providing in-depth insights into the genetic architecture of germplasm collections. Using this methodology, we investigated the genomic diversity of a panel of 288 diverse tomato (Solanum lycopersicum L.) accessions enriched in 'da serbo' (called 'de penjar' in Spain) long shelf life (LSL) materials (152 accessions) mostly originating from Italy and Spain. The rest of the materials originate from different countries and include landraces for fresh consumption, elite cultivars, heirlooms, and breeding lines. Apart from their LSL trait, 'da serbo' landraces are of remarkable interest for their resilience. We identified 32,799 high-quality SNPs, which were used for model ancestry population structure and non-parametric hierarchical clustering. Six genetic subgroups were revealed, clearly separating most 'da serbo' landraces, but also the Spanish germplasm, suggesting a subdivision of the population based on type and geographical provenance. Linkage disequilibrium (LD) in the collection decayed very rapidly within 5kb. We then investigated SNPs showing contrasted minor frequency allele (MAF) in 'da serbo' materials, resulting in the identification of high frequencies in this germplasm of several mutations in genes related to stress tolerance and fruit maturation such as CTR1 and JAR1. Finally, a mini-core collection of 58 accessions encompassing most of the diversity was selected for further exploitation of key traits. Our findings suggest the presence of a genetic footprint of the 'da serbo' germplasm selected in the Mediterranean basin. Moreover, we provide novel insights on LSL 'da serbo' germplasm as a promising source of alleles for tolerance to stresses. ; The authors thank the European Union Horizon 2020 Research and Innovation program for funding this research under grant agreement No 774244 (Breeding for Resilient, Efficient and Sustainable Organic Vegetable Production; BRESOV). ; Esposito, ...

Colombia is recognized worldwide for its megadiversity, which includes fauna, flora and microorganisms. The above is attributed to its highly ecosystemic complexity, derived from evolutionary processes in the Andes, the Orinoco, the Amazon and its Pacific and Caribbean coasts; regions where are located highlands, tropical jungles, wetlands, plains and deserts, among others. With about 0.77%, of the world's land area, the country holds approximately 10% of the plant and animal species known around the world. These genetic resources hold an important strategic value for the country, and their inventories are a fundamental tool for the analysis of their current option and use values, as well as, for taking actions related to their conservation, renewal and utilization. In this context, the Colombian government promoted the establishment of a National Germplasm Bank System for Food and Agriculture, which comprises vegetal, animal and microorganism species, The System is administrated by ICA and managed by Corpoica, through a Technical and Scientific Cooperation Agreement subscribed by the last two entities. From all the plant species accessions, held under ex situ conditions at Colombia, 70% of those are included in the above System. The remaining 30% correspond, mainly to species, held under the criteria of active banks. From the above and, in relation to plant genetic resources, Colombia has an ex situ National Germplasm Bank System, for Food and Agriculture, which complements in situ conservation processes done in farm by local producers. ; Colombia es reconocida en el mundo por su megadiversidad en fauna, flora y microorganismos, atribuida a su gran complejidad ecosistémica y a procesos evolutivos de los Andes, la Orinoquia, Amazonia y de sus costas Pacífica y Caribe, en los que se encuentran páramos, selvas tropicales, humedales, llanuras y desiertos, entre otros. Con una superficie continental de alrededor del 0,77% del área terrestre del mundo, alberga aproximadamente el 10% de las especies vegetales y animales conocidas. Estos recursos genéticos tienen un valor estratégico importante para el país, y sus inventarios son una herramienta fundamental para el análisis del estado actual y potencial de ellos y para la toma de decisiones sobre medidas de conservación y renovación. En este ámbito, el Gobierno colombiano facilitó la conformación del Sistema de Bancos de Germoplasma de la Nación para la Alimentación y la Agricultura, el cual figura en cabeza del ICA y es manejado por Corpoica por medio de un convenio de Cooperación Técnica y Científica, suscrito con el ICA. Del total de accesiones vegetales que posee Colombia, mantenidas en condiciones ex situ, el 70% se maneja en Corpoica. El 30% restante corresponde a bancos activos. En general, en Colombia existen bancos de germoplasma donde se conservan las especies en la modalidad ex situ, lo que complementa procesos de mantenimiento in situ, que incluyen materiales en fincas de los productores.

A field experiment was carried out at Dagwom farm at National Veterinary Research Institute (NVRI) Vom, in Jos South Local Government area of Plateau state Nigeria (Lat.09044N, long.08047E, altitude 1293.2 m above sea level) in 2013 and 2014 rainy seasons, to evaluate the genetic variability, correlation and path coefficient analysis in seed yield and related traits of cowpea. The treatments consisted of eighty (80) cowpea germplasm accessions obtained from International Institute for Tropical Agriculture (IITA) Ibadan Nigeria. The experiment was laid out in a Randomized Complete Block Design (RCBD) in two replicates. The Analysis of Variance (ANOVA) showed significant difference at (Plt3B0.01) among the entries for all the yield and related traits accessed. High phenotypic coefficient of variability (PCV) compared with genotypic coefficient of variability (GCV) coupled with low Environmental coefficient of variability (ECV) was observed for all the yield and related traits accessed. High broad sense heritability (H2B) and genetic advance (GAM () was observed for the entire yield and related traits accessed except days to maturity which recorded high heritability with moderate genetic advance. Significant positive correlation was observed between grain yield and number of pod per plant (r3D0.572**), hundred seed weight (r3D0.504**), pod length (r3D0.523**), number of secondary branches per plant (r3D0.450**), number of seed per pod (r3D0.431**), number of primary branches per plant (r3D0.339**) plant height (r3D0.285*), suggests that improving any of these characters will boost grain yield of cowpea. Path coefficient analysis showed that, number of pod per plant (P3D0.65), hundred seed weight (P3D0.54), number of seed per pod ((P3D0.29) number of secondary branches per plant ((P3D0.16), plant height (P3D0.05)), and pod length ((P3D0.04) contributed directly to grain yield. The result from this study therefore revealed that hundred seed weight, number of pod per plant, number of secondary branches per plant, ...

8 Pag., 6 Tabl. ; [EN] Early-maturing flint maize germplasm could be an important alternative for the development of new early-maturing commercial hybrids adapted to cooler summer regions. Our objective was to evaluate the performance of flint populations in crosses with four testers from different heterotic groups, as sources of new potential inbred lines. Ten flint maize populations were crossed to four inbred testers representing Reid Yellow Dent, Lancaster Sure Crop and two Spanish flint heterotic groups. Topcrosses were evaluated in four environments in north eastern Spain in 2001 and 2002. The main type of gene action expressed was additive. All populations except Enano Norteño/Vasco and Hembrilla Norteño/Vasco, had a higher specific combining ability in crosses with Reid Yellow Dent or Lancaster Sure Crop testers. Average yields were better when populations were crossed with dent lines rather than with the flint inbred line EP42. These results could be useful in the development of new inbred lines that would increase genetic variability present in commercial European flint maize. ; [ES] La evaluación de germoplasma liso precoz de maíz podría ser importante como una alternativa para el desarrollo de nuevos híbridos comerciales precoces adaptados a regiones templadas y potencialmente útiles para producir grano de alta calidad. Nuestros objetivos fueron evaluar el potencial de poblaciones lisas precoces y estimar el rendimiento de este germoplasma en cruzamientos con probadores de diferentes grupos heteróticos para el desarrollo de híbridos precoces de maíz grano. Diez poblaciones de maíz grano se cruzaron con cuatro probadores que representan Reid Yellow Dent, Lancaster Sure Crop y dos grupos heteróticos europeos. Los cruzamientos fueron evaluados en cuatro ambientes en el noreste de España durante 2001 y 2002, siendo la expresión génica expresada aditiva. Todas las poblaciones cruzadas, excepto Enano Norteño/Vasco y Hembrilla Norteño/Vasco, mostraron una mayor aptitud combinatoria específica en cruzamientos con probadores Reid Yellow Dent o Lancaster Surecrop. El mejor rendimiento medio se produjo cuando todas las poblaciones se cruzaron con las líneas dentadas en lugar de con la línea lisa EP42. Estos resultados podrían ser útiles para desarrollar nuevas líneas puras que incrementen la variabilidad presente en el maíz liso comercial europeo. ; Part of this work was financed by the Spanish Ministry of Education and Science project AGL2007- 64218/AGR, INIA (RF2007-00007-C05-04) and by Basque Government funds. ; Peer reviewed

The wear of the vegetation cover in Ecuador is increasing over the years, causing the loss of forest genetic resources, for this reason the objective was set: to implement a nursery for the multiplication of the native germplasm of the Protected Forest "La Perla ". This project was carried out with the support of the Decentralized Autonomous Government of the La Concordia canton. A 100 m2 nursery was built for the propagation of native plant species such as: Moral Fino (Maclura Tinctoria), Clavellin (Brownea herthae Harms), Guayacán Prieto (Tabebuia Guayacan), Pambil (Iriartea Deltoidea), Colorado Fino (Cupani Cinérea), Mambla (Erythrina Poeppigiana), Canelon (Cinnamomum Zeylanicum), Oak (Tabebuia pentaphylla), Jigua Negra (Nectandra cissiflora) and Wild Cocoa (Herrania balaensis). The seeds of the selected species prior to sowing were applied pre-germinative treatments. The substrate in the germination beds had a 1:1:1 ratio (10% sand, 10% black soil and 10% planting soil), for the cover a 3:1:1 ratio (30% fertilized soil 10% sand). 10% land). A physicochemical analysis of the substrate was carried out: Texture, CEC, Electrical Conductivity, Hydrogen Potential, MO. The percentage of germination and survival was evaluated. As a result, a higher percentage of germination was obtained in the following species: guayacán 78%, cannelloni 71% and wild cocoa 79%; while in the mambla species no germination was obtained, in the case of the oak there was a 98% take. Finally, it is concluded that knowing the phenology of each species is essential to apply the corresponding pre-germination processes, to obtain a higher percentage of germination. ; El desgaste de la cobertura vegetal en el Ecuador va en aumento con el transcurso de los años, provocando la pérdida de recursos genéticos forestales, por este motivo se planteó como objetivo: implementar un vivero para la multiplicación del germoplasma nativo del Bosque Protector "La Perla". Este proyecto se realizó mediante el apoyo del Gobierno Autónomo Descentralizado del ...

Chile is the origin of the Solanum tuberosum group Chilotanum corresponding to lowland tetraploid landraces. The most complete morphological description of the Chilean germplasm was published in 2008 in the Catalogue of Varieties of Native Potatoes from Chile, which describes 211 varieties. Two institutions of the Chilean government, INIA and SAG (Agricultural and Livestock Service of Chile), keep collections of 332 and 257 accessions, respectively; the varieties registered in the catalogue are included in the SAG collection. Thus, an important gap occurs between the number of varieties listed in the National Catalogue of Chile and the number of traditional varieties found in the Chilean collections of potatoes. In this work, two national collections of Chilean native germplasms (INIA-Remehue and SAG) were analysed via four microsatellite markers with the aims of (1) discriminating different genotypes in order to more accurately catalogue the current number of native Chilean varieties, (2) evaluating the diversity of genotypes potentially known with the same nomenclature by farmers, and (3) comparing allelic diversity of native germplasm with 44 commercial varieties. Of the 589 native accessions analysed, 320 different allelic phenotypes were found indicating that there are at least 320 different genotypes in the collections. Of these, 158 belonging to the INIA collection were not found in the SAG collection. These 158 new genotypes should increase the number of known Chilean varieties. As expected, different genotypes were known under the same popular name. In terms of allelic diversity, the group of commercial varieties contained a subset of the alleles within the collection of SAG and INIA-Remehue. ; Peer Review

Dottorato di ricerca in Ortoflorofrutticoltura ; Globe artichoke and cardoon, belonging to the Asteraceae (Compositae) family, are herbaceous perennial plants native to the Mediterranean area, which are traditionally grown as vegetables for the heads and the fleshy petiole leaves, respectively. Italy is the richest reserve of globe artichoke (Cynara cardunculus var. scolymus L.) autochthonous germplasm, which is vegetatively propagated and well adapted to the different pedoclimatic conditions of the Country. On the basis of head harvest time, these traditionally grown genetic resources are classified as early or late distinct clonal varietal groups. Other distinct varietal groups are also identified, according to the morphological traits of the head, into four main typologies such as Violetto di Sicilia, Spinoso Sardo, Catanese and Romanesco. In Central Italian environments, the Romanesco type, characterized by a spherical or sub-spherical and non-spiny green-violet heads, is widespread. In the last years, the development of in vitro technologies allowed the propagation of Romanesco globe artichoke type and its rapid expansion. As a result, the Romanesco clone C3 has been in vitro micropropagated and widely distributed to the farmers. This clone has replaced many Romanesco landraces traditionally grown in the Latium Region and has led either to a significant erosion of local genetic resources or a loss of diversity. Moreover, introduction of new seed-propagated F1 hybrids such as Madrigal, Concerto, Opal, Tema, and Romolo, well suited to market demands, represents a further factor increasing the risk of genetic erosion for autochthonous germplasm. As regards Italian cultivated cardoon (Cynara cardunculus var. altilis DC) germplasm, there are few studies on its genetic characterization and identification and there is a lack of information about the genetic variability existing within and among accessions. For the wild cardoon (Cynara cardunculus var. sylvestris Lam.), no specialized crop is present and it represents mainly a weed in Italian environments. The great variability existing in Cynara spp. has not been described, the nomenclature of Italian germplasm is not always very clear since there are many cases of homonyms. In addition to this risk of genetic erosion, in the last years, Italian globe artichoke sector is facing a crisis due principally to the appearance on the market of foreign products and to the high labor cost required for crop cultivation and harvesting. In order to overcome this crisis several possible uses of Cynara spp. were considered such as i) seeds for oil, ii) roots for inulin, iii) biomass for energy, iv) fiber for pulp and paper and as potential reinforcement in polymer composites v) green forage for ruminant feeding, vi) proteins as natural rennet for traditional cheese making, and vii) entire plant for metalaccumulation. These new possible applications of the crop are linked principally to the European Union research support on new agricultural by-products (industrial raw materials) and led to an increasing interest also in aboveground globe artichoke biomass. Considering these preliminary remarks, a strategy for valorizing Italian germplasm using biomass and biocompound production has been carried out during the three years of PhD program. In particular, nine Italian spring landraces (Ascolano, Campagnano, Castellammare, Jesino, Montelupone A, Montelupone B, Bianco di Pertosa, Pisa and Tondo Rosso di Paestum), ten 'Romanesco' clones (S2, S3, S5, S11, S17, S18, S22,S23, Grato 1 and Campagnano), seven cultivated cardoon accessions (AFB, AFFG, AFGR, AFGI, AFM, AFM2, AFN) and AFS wild cardoon belonging to the joint germplasm collection of Tuscia University and ENEA have been considered in our PhD study. Open field trials were conducted at the Experimental Field Station of ARSIAL (Latium Regional Agency for the Development and the Innovation of Agriculture) in Cerveteri, Rome and in Tarquinia, Viterbo while greenhouse experiments were carried out at the Experimental Station of Tuscia University in Viterbo (Italy). The first objective of PhD work consisted in (i) characterizing agro-morphologically Italian germplasm using UPOV descriptors, (ii) assessing the genetic variability existing within and among landraces/clones and (iii) identifying and preserving genetic resources for the development of future plant breeding programs. As a result of this characterization, three genotypes have been selected and registered under the names of Michelangelo, Donatello and Raffaello. In order to analyze Italian Cynara spp. germplasm also from a biomass point of view, different traits explaining plant vigor and dry matter production have been considered. The aerial biomass yield resulted very high underlining the possibility of using this crop as raw industrial material. In particular, some genotypes, such as Ascolano, Campagnano, Pisa, Bianco di Pertosa for globe artichoke and AFFG and AFM for cardoon showed the highest biomass yield. A focal point of PhD program was to set up biocompound extraction methods and analysis techniques to optimize polyphenol recovery from biomass of Cynara spp at a laboratory scale. In particular, conventional (i.e. Soxhlet and maceration) and modern extraction techniques (such as Microwave-Assisted Extraction MAE, and Accelerated Solvent Extraction ASE) have been compared and, using a full two-level factorial experimental design, ASE was found as the best extraction technique which allows to reduce extraction time and solvent consumption, increase nutraceutical yield and improvement of extract quality. Moreover, the kinetics of biomass and biocompound production has been evaluated and the optimal physiological stage to collect plant material grown in open field has been identified. Biochemical characterization has been performed using the methods set up and collecting plant material in the optimal physiological stage identified in order to distinguish which genotypes were more suitable for bio-compound production purpose. As a result of morphological and biochemical characterization, genotypes were well distinguished from each other and were identified those which are the most suitable for food use, for biomass production and/or for dual-production (food and non-food). The last focal point of PhD program was the development of an alternative technique for biomass and biocompound production in greenhouse grown conditions. The adaptation of globe artichoke and cardoon genotypes to floating system has been evaluated and the biochemical and molecular responses of the plant to the salinity stress have been also investigated. Results obtained in the three PhD years, highlighted the possibility of using successfully some Cynara spp. genotypes for biomass and bio-compound production, in particular in open field condition. Also the real prospect of using some globe artichoke genotypes for food and non-food dual-production (biomass for biocompound extraction and heads for human food) has been underlined. ; Il carciofo e il cardo, appartenenti alla famiglia delle Asteraceae (Compositae), sono delle piante erbacee, perenni, originarie del bacino del Mediterraneo e tradizionalmente coltivate a scopo alimentare rispettivamente per i capolini e le foglie carnose. L'Italia rappresenta una delle più ricche riserve di germoplasma autoctono di carciofo (Cynara cardunculus var. scolymus L.), il quale è propagato vegetativamente e ben adattato alle differenti condizioni pedoclimatiche del nostro Paese. Sulla base dell'epoca di maturazione commerciale dei capolini, i genotipi di carciofo vengono classificati in tipologie precoci e autunnali. Un altro criterio di classificazione, basato sulle caratteristiche morfologiche dei capolini, suddivide i suddetti genotipi in quattro gruppi varietali: 'Violetto di Sicilia', dello 'Spinoso Sardo', del 'Catanese' e del 'Romanesco'. La tipologia 'Romanesco', caratterizzata da capolini inermi di forma rotonda o ellittica e di colore verde-viola, è molto diffusa negli ambienti di coltivazione cinaricola dell'Italia centrale. Negli ultimi anni, la messa a punto della tecnica di propagazione in vitro per il carciofo, ha portato ad una rapida diffusione di cloni della tipologia 'Romanesco'. In particolare, il clone C3 propagato in vitro ha conosciuto una grande diffusione nelle aree di coltivazione cinaricola, sostituendo molte varietà afferenti alla tipologia 'Romanesco' tradizionalmente coltivate nel Lazio e determinando rischi di erosione genetica per queste risorse genetiche. Inoltre, l'introduzione sul mercato di nuovi ibridi F1 come Madrigal, Concerto, Opal, Tema, and Romolo, meglio rispondenti alle richieste dei consumatori, rappresenta un ulteriore fattore di rischio per la perdita del germoplasma autoctono. Per quanto riguarda il cardo coltivato (Cynara cardunculus var. altilis DC), esistono pochi studi sulla caratterizzazione genetica e sull'identificazione del germoplasma autoctono e mancano dati riguardanti la variabilità genetica esistente tra ed entro accessioni diverse. Per il cardo selvatico (Cynara cardunculus var. sylvestris Lam.), non sono presenti coltivazioni specializzate ed esso rappresenta un'infestante negli ambienti di coltivazione cinaricola italiani. L'ampia variabilità esistente nel germoplasma di Cynara spp. non è stata descritta; la nomenclatura delle risorse genetiche non è spesso chiara e spesso si trovano casi di omonimia. Oltre a questo rischio di erosione genetica, negli ultimi anni assistiamo anche ad una forte crisi del settore cinaricolo dovuta alla comparsa sul mercato di prodotti stranieri e all'alto costo di produzione e di raccolta previsti dalla coltura. Negli ultimi decenni, per far fronte a questa crisi, sono stati considerati diversi possibili usi per la specie quali, ad esempio, i) la produzione di olio dai semi; ii) l'estrazione di inulina dalle radici; iii) la produzione di energia dalla biomassa; iv) l'estrazione della fibra per l'industria cartaria; v) la produzione di foraggio da destinare all'alimentazione animale; vi) la produzione di formaggi come caglio vegetale mediante impiego di estratti fiorali; vii) l'accumulo di metalli pesanti nella pianta. Lo studio di questi nuovi possibili utilizzi è stato reso possibile grazie ai finanziamenti della Comunità Europea che ha incentivato e supportato la ricerca nel settore delle agrorisorse e ha portato anche ad un forte interesse nell'uso della biomassa di carciofo. Nel corso dei tre anni di dottorato è stata portata avanti una strategia di ricerca volta alla valorizzazione del germoplasma italiano di carciofo e cardo basata sull'uso della biomassa per l'estrazione di biomolecole. In particolare, sono stati considerati nove genotipi autoctoni primaverili (Ascolano, Campagnano, Castellammare, Jesino, Montelupone A, Montelupone B, Bianco di Pertosa, Pisa and Tondo Rosso di Paestum), dieci cloni della tipologia 'Romanesco' (S2, S3, S5, S11, S17, S18, S22, S23, Grato 1 and Campagnano), sette genotipi di cardo coltivato (AFB, AFFG, AFGR, AFGI, AFM, AFM2, AFN) e un genotipo di cardo selvatico (AFS), tutti appartenenti alla collezione di germoplasma dell'Università della Tuscia e dell'ENEA. Le prove sperimentali di campo sono state svolte presso l'Azienda sperimentale ARSIAL (Agenzia Regionale per lo Sviluppo e l'Innovazione in Agricoltura) di Cerveteri (Roma) e di Tarquinia (Viterbo), mentre le prove di serra sono state condotte nella Azienda Sperimentale dell'Università della Tuscia, a Viterbo (Italia). Il primo obiettivo del dottorato ha riguardato i) la caratterizzazione agro-morfologica del germoplasma italiano per mezzo dei descrittori UPOV, ii) la valutazione della variabilità genetica esistente tra ed entro i genotipi, e iii) l'identificazione e la conservazione delle risorse genetiche in collezione per lo sviluppo futuro di programmi di miglioramento genetico. La caratterizzazione del germoplasma ha portato alla selezione di tre genotipi validi per la produzione edule che sono stati validati e proposti per l'iscrizione al Registro Nazionale delle Varietà con i nomi di Michelangelo, Donatello e Raffaello. Al fine di caratterizzare il germoplasma anche da un punto di vista della biomassa, sono stati anche considerati diversi caratteri morfologici atti a descrivere il vigore della pianta e a quantificare la produzione di sostanza secca. La produzione di biomassa è risultata davvero molto interessante nel nostro lavoro e si è sottolineato il grande potenziale di utilizzo della coltura nel settore industriale. Alcuni genotipi come Ascolano, Campagnano, Pisa e Bianco di Pertosa, per il carciofo, e AFFG e AFM, per il cardo, sono risultati davvero interessanti dal punto di vista della produzione di biomassa. Un altro importante obiettivo del dottorato è stato quello di mettere a punto un metodo per l'estrazione di polifenoli al fine di ottimizzare le rese. Sono state messe a confronto tecniche convenzionali (ad esempio metodo Soxhlet e macerazione) ed altre più innovative (ad esempio Microwave Assisted Extraction - MAE e Accelerated Solvent Extraction - ASE). La tecnica ASE ha fornito i migliori risultati, consentendo anche di ridurre i tempi d'estrazione e il consumo di solvente, fornendo al tempo stesso alte rese e elevata qualità degli estratti. E' stato anche condotto lo studio della cinetica di accumulo della biomassa e delle biomolecole in campo al fine di individuare il momento migliore per la raccolta del materiale in campo ed ottimizzare le rese. Una volta messo a punto il metodo d'estrazione e individuata l'epoca ottimale per il prelievo delle biomasse in campo, si è andati ad effettuate le estrazioni al fine di caratterizzare biochimicamente i genotipi in prova e di selezionere quelli più rispondenti a tale attitudine. La caratterizzazione morfologica e biochimica hanno permesso di ben identificare i genotipi e di selezionare quelli più adatti per la produzione di capolini ('food production'), di biomassa o per la duplice attitudine (food and non-food). Nel corso del dottorato si è anche valutato un sistema alternativo per la produzione di biomassa e di biomolecole in serra. E' stata valutata l'adattabilità del carciofo e del cardo al sistema di coltivazione fuori suolo (floating system), soprattutto per evidenziare risposta biochimica e molecolare delle piante sottoposte allo stress salino in termini di aumento nella produzione di sostanze fenoliche. I risultati ottenuti nel corso del dottorato hanno messo in luce la reale possibilità di usare alcuni genotipi di carciofo e di cardo per la produzione edule, altri per quella di biomassa e di biomolecole, soprattutto in condizioni di pieno campo. Si è inoltre delineata una reale prospettiva per l'impiego di alcuni genotipi di carciofo in una duplice destinazione commerciale (biomassa per l'estrazione di biomolecole e capolini per la destinazione alimentare).