http://http://dspace.unitus.it:80 The DSpace digital repository system captures, stores, indexes, preserves, and distributes digital research material. Wed, 19 Jun 2013 04:50:18 GMT 2013-06-19T04:50:18Z http://hdl.handle.net/2067/2174 Title: Fruit quality of Italian pomegranate (Punica granatum L.) autochthonous varieties Authors: Cristofori, Valerio; Caruso, Donatella; Latini, Gabriele; Dell'Agli, Mario; Cammilli, Corrado; Rugini, Eddo; Bignami, Cristina; Muleo, Rosario Abstract: Pomegranate is getting an increasing attention for its health-promoting effects. Collection and characterization of plants of local sources has been performed, and five accessions have been propagated and cultivated in a collection field for extra situ investigations. Accessions differ for pomological traits and chemical composition. Three of them, MG1, MG2, and MG3, belong to typology with low-medium acidity and high sugar content, while the other two, Tordimonte A and B, belong to typology with high acidity. In the juice and in the peels’ extract of Tordimonte A accession a high level of punicalin has been found through chromatographic determinations, while the presence of punicalagin was found in the juice of accession MG1. The accessions MG1, MG2, and MG3 seem particularly suitable for direct commercialization of fruits due to the fruit traits and quality (sweet varieties), while Tordimonte A and B could be valuable for juice processing (sour varieties). Description: L'articolo è disponibile sul sito dell'editore http://www.springerlink.com Fri, 31 Dec 2010 23:00:00 GMT http://hdl.handle.net/2067/2174 2010-12-31T23:00:00Z http://hdl.handle.net/2067/2181 Title: Olea Authors: Rugini, Eddo; De Pace, Ciro; Gutierréz-Pesce, Patricia; Muleo, Rosario Abstract: The genus Olea contains about 30 species were grouped into three subgenera, Tetrapilus, Paniculatae, and Olea (cultivated olive and wild relatives), found in Asia, Australia and Asia, Africa and Europe, respectively. The species O. europaea L. includes six subspecies: Olea europaea L. ssp. europaea (the Mediterranean olives); O. e. laperrinei (distributed in Saharan massifs of Hoggar, Aïr, Jebel Marra in Algeria); O. e. cuspidata (which moved from South Africa to Egypt, East Australian areas and Hawaii, and from Arabia to northern India and Southwest China); O. e. guanchica (Canary Islands); O. e. maroccana (southwestern Morocco); and O. e. cerasiformis (Madeira). Using molecular markers, it has been ascertained that the Mediterranean olives include the cultivated types (O. europaea L. ssp. europaea var. sativa), the true wild oleaster (O. e. e. var. sylvestris), and the feral form olevaster from seedlings raised from seeds of the cultivated types. The oleaster has a narrow range of distribution and it is often mistaken for olevaster. Recolonization of the Mediterranean basin by Oleaster occurred after the last glacial event, from refuges located in both eastern and western Mediterranean basin areas toward southern Europe. Oleaster is a source of rootstock for propagating new improved cultivated varieties. Cultivated and wild forms have the same diploid chromosome number (2n = 46) and are fully interfertile. Triploid and tetraploid genotypes have been isolated from cultivated O.e.e., but polyploid forms have been found in endangered natural populations of O. e. guancica (tetraploid) and O. e. maroccana (hexaploid). Individual oleaster trees showing superior performance for size and/or oil content of fruit were selected empirically during olive domestication and propagated vegetatively as clones using cuttings that were planted directly or, more recently, grafted onto indigenous oleasters. Genetic markers linked for most important agronomic traits, such as size of the tree, content of secondary products of fruit, flowering induction, oil quality, and biotic and abiotic resistance, will help introgression by conventional breeding of oleaster trait-enhancing genes into cultivated olive. Successful results were difficult to achieve due to both the complex genetic basis of the traits to be improved and the long juvenile period of the progenies that delays the expression of the target traits. In vitro techniques to regenerate doubled haploids from hybrids or somaclonal variation induction may complement classical breeding procedures. Genetic transformation could speed up the development of new genotypes, and transgenic olive plants with modified growth habit and putative induced disease resistance are being tested under filed conditions. However, the development of an efficient regeneration method from mature tissue is the limiting factor for the routine application of this technology to olive genetic improvement. Description: L'articolo è disponibile sul sito dell'editore http://www.springerlink.com Fri, 31 Dec 2010 23:00:00 GMT http://hdl.handle.net/2067/2181 2010-12-31T23:00:00Z http://hdl.handle.net/2067/1932 Title: Salicylic acid induces H2O2 production and endochitinase gene expression but not ethylene biosynthesis in Castanea sativa in vitro model system Authors: Harfouche, Antoine L.; Rugini, Eddo; Mencarelli, Fabio; Botondi, Rinaldo; Muleo, Rosario Abstract: Salicylic acid (SA), ethylene (ET), and wounding are all known to influence plant defense response. Experiments attempting to determine SA’s relation to ET biosynthesis and defense gene expression have shown conflicting results. To confront this, we developed an in vitro model system to investigate how SA affects ET biosynthesis, hydrogen peroxide (H2O2) production and endochitinase gene expression in the European chestnut. ET measurements of in vitro shoots indicated a critical time point for SA exogenous application, enabling us to study its effects independent of ET. In addition, ET measurements demonstrated that its own increased biosynthesis was a response to wounding but not to SA treatment. Application of the ET biosynthesis inhibitor, aminoethoxyvinylglycine (AVG), on wounded and SA-treated shoots blocked wounding-induced ET production. Interestingly, SA inhibited ET production, but to a lesser extent than AVG. Additionally, SA also induced the accumulation of endochitinase transcript level. Likewise, a sensitive tissue-print assay showed that SA further increased the level of H2O2. Yet, SA-induced endochitinase gene expression and SA-enhanced H2O2 production levels were independent of ET. The cumulative results indicate that SA acts as an inducer of endochitinase PR gene expression and of H2O2 oxidative burst. This suggests that SA is a component of the signal transduction pathway leading to defense against pathogens in chestnut. Further, the model system developed for this experiment should facilitate the deciphering of defense signaling pathways and their cross-talk. Moreover, it should also benefit the study of trees of long generation time that are known to be recalcitrant to in vitro studies. Description: L'articolo é disponibile sul sito dell'editore: http://www.sciencedirect.com Mon, 31 Dec 2007 23:00:00 GMT http://hdl.handle.net/2067/1932 2007-12-31T23:00:00Z http://hdl.handle.net/2067/1933 Title: Mutation scanning and genotyping by high-resolution DNA melting analysis in olive germplasm Authors: Muleo, Rosario; Colao, Maria Chiara; Miano, Dario; Cirilli, Marco; Intrieri, Maria Carmela; Baldoni, Luciana; Rugini, Eddo Abstract: The application of high-resolution melting (HRM) analysis of DNA is reported l'or scanning and genotyping Olea europaea germplasm. To test the sensitivity of the method, a functional gene marker, phytochrome A (phyA), was used, since this gene is correlated with important traits for the ecology of the species. We have designed a set of oligos able to produce amplicons of 307 bp to scan for the presence of single polymorphic mutations in a specific phyA fragment encompassing the chromophore altachment site (Cys323). The presence of mutations for substitution, either homozygous or heterozygous, was easily detected by melting curve analysis in a high-resolution melter. It has been established that the sensitivity of the HRM analysis can be signiticantly improved designing specific primers very close to the mutation sites. Ali SNPs found were contirmed by sequence analyses and ARMS-PCR. The method has also been confirmed to be very powerful for the visualization of microsatellite (SSR) length polymorphisms. HRM analysis has a very high reproducibility and sensitivity for detecting SNPs and SSRs, allowing olive cultivar genotyping and resulting in an informative, easy, and low-cost method able to greatly reduce the operating time. Description: L'articolo é disponibile sul sito dell'editore: http://www.nrcresearchpress.com Wed, 31 Dec 2008 23:00:00 GMT http://hdl.handle.net/2067/1933 2008-12-31T23:00:00Z http://hdl.handle.net/2067/2176 Title: Optimisation of regeneration and maintenance of morphogenic callus in pear (Pyrus communis L.) by simple and double regeneration techniques Authors: Abdollahi, Hamid; Muleo, Rosario; Rugini, Eddo Abstract: The purpose of our work was to improve the regeneration capacity of leaf explants and the maintenance of shoot morphogenesis in callus of six pear cultivars: Abate Fetel, Conference, Dar Gazi, Harrow Sweet, Kaiser and Williams, by altering the composition of both regeneration and proliferation media of explant donor shoots, and choosing the right type of explant. Regeneration capacity of leaf explants collected from in vitro shoots has been improved in the majority of cultivars also due to shoot preconditioning. For the first time, long term morphogenic callus production and maintenance have been established in some cultivars by a “double regeneration”. Using this technique, morphogenic callus of two cultivars, ‘Dar Gazi’ and ‘Conference’, was maintained for several subcultures but only when they were initiated from small leaflets – less than 2–3 mm long – which had been collected from the neoformed adventitious buds. MS medium [Murashige, T., Skoog, F., 1962. A revised medium for rapid growth and bioassay with tobacco tissue culture. Physiol. Plant. 15, 473–497] proved to be an efficient regeneration medium by stimulating adventitious buds, while the explants of all cultivars, except for Kaiser, showed a high regeneration capacity when they were collected from shoots proliferated on modified QL medium [Quoirin, M, Lepoivre, P., Boxus, P., 1977. Un premier bilan de dix annees de recherche sur les cultures de meristemes et la multiplication in vitro de fruitiers ligneux. Compte rendu des recherches, Station des Cultures Fruitieres et Maraicheres de Gembloux (1976–1977), 93–117]. This medium conferred leaf expansion, overcoming 90% of regeneration in explants of cv Dar Gazi and Williams. Well expanded leaves were obtained and collected by rooting the shoots, while regeneration percentage was not improved and the number of adventitious shoots was increased in most cultivars, reaching up to 10 shoots per explant. When cefotaxime at 200 mg/l, which is normally effective in controlling Agrobacterium, was used for genetic transformation, regeneration percentage and number of shoots per explant (in leaf explants collected from rooted shoots) were increased and a uniform bud regeneration on all the leaf surface was promoted. Description: L'articolo è disponibile sul sito dell'editore http://www.sciencedirect.com Sat, 31 Dec 2005 23:00:00 GMT http://hdl.handle.net/2067/2176 2005-12-31T23:00:00Z http://hdl.handle.net/2067/2170 Title: Olive Authors: Rugini, Eddo; Gutiérrez-Pesce, Patricia; Muleo, Rosario Abstract: Biochemical and molecular procedures have been developed for olive genotyping, for taxonomy between cultivated and wild olives, for phylogenetic studies of cultivars, and for identification of usable markers linked to the most important agronomic traits, such as size of the tree, flowering induction, apical dominance, productivity, self-fertility, quantity and quality of oil and secondary products of fruit, biotic and abiotic resistance. These characters could be introgressed into cultivars by conventional breeding or through transgeny. Successful results by classical breeding are difficult to obtain due to the different flower fertility and the long juvenile period of the progenies. The low efficiency of modern genetic improvement techniques suggests that genetic transformation techniques could speed up the development of new genotypes; however, the development of efficient regeneration methods from mature tissue is the limiting factor for applying this technology, in olive. Transgenic olive plants with modified growth habit and putative induced disease resistance are under filed conditions to test their phenotype. Other attempts of genetic improvement such as clonal selection, mutation through -irradiation, protoplast technology, haploid, changes in ploidy level, somaclonal variation, and somatic hybridization are discussed and reviewed. Description: L'articolo è disponibile sul sito dell'editore http://onlinelibrary.wiley.com/ Mon, 31 Dec 2007 23:00:00 GMT http://hdl.handle.net/2067/2170 2007-12-31T23:00:00Z http://hdl.handle.net/2067/2172 Title: In vitro system for studying the interaction between Erwinia amylovora and genotypes of pear Authors: Abdollahi, Hamid; Rugini, Eddo; Ruzzi, Maurizio; Muleo, Rosario Abstract: A new in vitro system is described for studying an interaction between Erwinia amylovoraand Pyrus communis (L.). The system uses single shoots placed onto the solid medium, and it enables to detect changes in pH of the medium and differential appearance of shoot necrosis. Shoots of susceptible cultivar (Williams) and tolerant cultivar (Harrow Sweet) were compared measuring the necrosis rate along the in vitroshoots and the pH variation following proton extrusion of both plant and pathogen. Shoots acidified differentially the culture medium depending on the presence of the pathogen, cultivar susceptibility and shoot inoculation methods. Differences in the tolerance level against pathogen among the cultivars were distinguishable only when the shoots were inoculated at the basal end. In susceptible cultivar, the necrosis appeared after 48 h of inoculation, while in tolerant cultivars after 72 h. This system is repeatable and more reliable than already known methods, such as in vitroleaf explants or in vivoplants; it can be used all around the year to test the gene expression and products essential to characterize the genes involved in the pathogenesis. This system showed the effects of E. amylovoraon the photosystem dependent system of host cells, confirmed by the effects of pathogen attack on the variation of chlorophyll a and chlorophyll b ratios and positive effects of light on the appearance of the first disease symptoms. Description: L'articolo è disponibile sul sito del nuovo editore http://www.springerlink.com Wed, 31 Dec 2003 23:00:00 GMT http://hdl.handle.net/2067/2172 2003-12-31T23:00:00Z