Kiwifruit (genus Actinidia) is an important horticultural crop grown in the temperate regions. The four world’s largest producers are China, Italy, New Zealand and Chile. More than 50 species are recognized in the genus but the principal species in cultivation are A. deliciosa and A. chinensis. In Italy, as well as in many other countries, the kiwifruit crop has been considered to be relatively disease free and then no certification system for this species has been developed to regulate importation of propagation plant material in the European Union. During the last years a number of fungal and bacterial diseases have been recorded such as Botrytis cinerea and Pseudomonas syringae pv. actinidiae. Since 2003, several viruses and virus-like diseases have been identified and more recent studies demonstrated that Actinidia spp can be infected by a wide range of viral agents. In collaboration with the University of Auckland we have been detected thirteen different viral species on kiwifruit plants. During the three years of my PhD I worked on the characterization of Cucumber mosaic virus (CMV) and Pelargonium zonate spot virus (PZSV). The determination of causal agents has been based on host range, symptom expression in the test plant species and morphological properties of the virus particles using transmission electron microscopy (TEM) and using specific oligonucleotide primers in reverse transcription-polymerase chain reaction (RT-PCR). Both viruses induced several symptoms on kiwifruit plants. Moreover with new technologies such as high-throughput sequencing we detected additional viruses, a new member of the family Closteroviridae and a new member of the family Totiviridae. Taking together all results of my studies it is clear that, in order to minimize the risk of serious viral disease in kiwifruit, it is vital to use virus-free propagation material in order to prevent the spread of these viruses.

La tematica dell’abuso del diritto in campo fiscale ha conosciuto, negli ultimi anni, una diffusione particolarmente rilevante. Questo lavoro, dopo una necessaria premessa introduttiva alla problematica, affronta l’abuso del diritto in campo tributario tramite l’analisi degli strumenti classici dell’ermenutica, constatando come si arrivi ad un intreccio tra lo strumento della clausola generale anti-abuso e il principio di divieto d’abuso del diritto sviluppatosi a livello europeo, concretizzazione del più ampio principio dell’effettività del diritto dell’Unione Europea. L’analisi prende a modello, da un lato, la clausola generale anti-abuso tedesca, adottata già nel primo dopoguerra, e le sue diverse modifiche legislative occorse negli anni, e dall’altro, il principio europeo di divieto d’abuso del diritto. L’esame congiunto rivela un cortocircuito interpretativo, posto che il principio europeo espone gli stessi concetti della clausola nazionale tedesca pre riforma, la quale, in seguito, alle sentenze Halifax e Cadbury Schweppes, ha subito un’importante modifica, cosicchè la clausola generale abbisogna ora del princìpio europeo per essere interpretata. La tesi evidenzia, inoltre, come tale circuito sia aggravato anche da tensioni interne alle stesse Istituzioni europee, posto che, nonostante l’esistenza di un principio di elaborazione giurisprudenziale, gli Stati Membri sono stati invitati ad introdurre una clausola generale anti-abuso, la cui formulazione rimanda al principio di divieto d’abuso del diritto elaborato dalla Corte di Giustizia. / During the last years the phenomenon of tax abuse has spread significantly. This work, after an essential introduction of the problematic, deals with tax abuse through classical methods of hermeneutics to establish a direct connection between general anti-abuse clauses and the european principle of prohibition of tax abuse, which originates from the more comprehensive european princìple of effectiveness. The analysis compares two experiences, on one side the german anti-abuse clause, already implemented after the First World War, and on the other, the european princìple of prohibition of tax abuse. An interpretative “short-circuit” results from this study as the european princìple affirms the same concepts of the german anti-abuse clause before the last reform. The national clause was significantly modified after the pubblications of Halifax and Cadbury Schweppes, with the consequences that nowadays, for interpreting this rule, it’s necessary to refer to the european principle of prohibition of tax abuse. Moreover the work highlights how this circular mechanism is worsen by the same European Institutions, as Member States, despite the existence of a jurisprudential princìple, have been invited to introduce a general anti-abuse clause in their tax systems, that is clearly based on the concepts expressed by the European Court of Justice.

The thesis deals with the concept of presumptions, and in particular of legal presumptions, in the context of national tax systems (Italy and Belgium) and EU law. The purpose was to investigate the concept of legal presumption under a twofold comparative perspective. After having provided a general overview of the common core concept of presumption in the European context, an insight in the national approach to legal presumptions was given by examining two different national experiences, namely the Italian and Belgian tax systems. At this stage, the Constitutional framework and some of the most interesting and relevant at EU level presumptive measures were explored, with a view to underlining possible divergences and common grounds. The concept of (national) legal presumption was then investigated in the context of EU law, with the attempt to systematize under a uniform perspective a matter which has been traditionally dealt with either from the merely national point of view or, at EU level, through a fragmented form. In this instance, the EU law relevant framework and the most significant EUCJ case-law, in particular in the field of customs duties, VAT, on the issue of the repayment of taxes levied in breach of EU law and in the area of direct taxation, were examined so as to construe the overall EU approach to national legal presumptions. This was done with the finality of determining if and to what extent a common analytical framework may be identified, from which were extracted certain criteria governing the compatibility of national legal presumptions with EU law.

Value added tax (VAT), with its specific and unique feature as a neutral taxation, has spread rapidly around the world since its first adoption in Europe. China has also chosen to adopt VAT in an attempt to promote its economic development. In 2012, China started a new round of reform of VAT to extend its scope to industries which previously were liable to business tax. One of the most difficult problems is the rebuilding of the VAT deduction system therein. Although Europe faces its own problems and difficulties in the process of perfection and coordination of VAT, as the cradle of VAT it could still provide helpful insights for the ongoing VAT reform in China. Based on the analysis of the VAT system and, in particular, the right to deduct input VAT in Europe, combined with the development and special conditions of VAT in China, I propose several recommendations for the ongoing VAT reform in China and its future legislation. First, on the overall level, it is important to review the principle of neutrality in VAT, and rather than to view it as a natural result of the operation of the VAT system, its role as a rule to be complied with. Second, with regard to the design of the VAT deduction system, I argue that: (1) it is not necessary to establish VAT deduction as a substantive right of the taxpayer; (2) it is necessary to expand the scope of deductible items in China, especially in relation to fixed capital investment; (3) it is urgent to improve the treatment of the excess amount of deductible input VAT. Finally, suggestions are given supporting the construction of the related procedural legislation.

L'obbiettivo della ricerca è l'analisi del riassetto istituzionale dovuto alla crisi economica. Il progetto di ricerca parte da un’analisi della formazione della moneta unica e dell’Unione economica e monetaria, per proseguire attraverso l’analisi dello stato di avanzamento delle politiche economiche e monetarie mediante la ridefinizione degli assetti giuridici ed istituzionali, come diretta conseguenza della crisi economica. Si prende infine in considerazione l’accelerazione di alcuni processi d’integrazione che hanno messo in discussione il ruolo di alcune Istituzioni partendo dalla natura stessa del metodo comunitario e del processo di legittimità democratica alla base del consolidamento e dello sviluppo dell’Unione economica e monetaria. Fino ad arrivare allo statuto speciale ottenuto dal Regno Unito che mette in discussione l'assetto stesso del progetto europeo, decretando un Europa a più velocità, frutto di una specifica visione di un Europa regolatori. / The propose of this research is to analyze the future of the European project due to the changes of the economic crisis. The research is based on a deep analysis of European economic and monetary policies, starting from the creation of the single currency through the construction of the Economic and Monetary Union, until the impact of the debt crisis on the European Governance and institutions. The research project analyses the legal and political arrangements that have queries the Community method in favor of the intergovernmental method. It is analyzed the acceleration of certain processes of integration/desegregation of the European project that have questioned the role of some institutions, their accountability and legitimacy, until the UK special status that have create de facto a legal multi-speed Europe.

La tesi di ricerca analizza uno dei problemi più rilevanti: l’elusione fiscale sulla fiscalità diretta effettuata a livello europeo, tra l'uso abusivo delle libertà europee. Il punto di partenza è lo stato della legislazione fiscale nell'Unione Europea come conseguenza della difficoltà di raggiungere una vera e propria armonizzazione giuridica come risultato del cosiddetto veto fiscale. L'origine del cosiddetto ostacolo è la mancanza di un interesse fiscale comune tra gli Stati membri. La politica fiscale è un’area strategica per tutti gli Stati, quindi è impossibile legiferare accontentando tutti. Questa situazione costituisce un ostacolo al processo di integrazione giuridica ed economica e allo sviluppo del Mercato Interno, è per questo motivo che la Corte di giustizia europea, attuando in qualità di uno dei principali attori in quello che viene chiamata l'armonizzazione negativa e in pro di tale integrazione regionale, è valutato quelle libertà verso una interpretazione protezionista. Questa interpretazione protezionista è quella impiegata dagli operatori economici come strumento abusivo verso il quale eludere il complimento della norma fiscale nazionale. In questa situazione e con il fine di ottenere un sistema fiscale giusto, vero ed efficace, considerammo che il modo migliore per affrontare queste pratiche non è altro che attraverso l'uso della dottrina sul divieto del abuso del diritto europeo elaborata dalla Corte di giustizia, permettendo agli Stati membri di legiferare disposizioni che limitino l'esercizio delle libertà europee. Il problema dell'impiego della riferita teoria come strumento anti-elusivo si trova nella natura giuridica di essa. Questa è stata qualificata come principio interpretativo e non come un principio generale del Diritto Europeo, quindi se vogliamo utilizzarla come strumento anti-abuso bisognerà essere codificata negli Ordinamenti nazionali sotto forma di clausola generale anti-abuso mediante cui consentire all'autorità tributaria corrispondente ad agire di conseguenza. Codificazione che dovrà essere conforme al Diritto Europeo. / This thesis examines one of the most important problems in the tax arena: tax avoidance on direct taxation at European level, through the abuse of fundamental freedoms. The starting point is the state of tax law in the European Union as a consequence of the difficulty of reaching a real legal harmonization in this area as a result of the so-called veto. The origin of this obstacle is the lack of a common fiscal interest between Member States. Fiscal policy is a strategic area for all States, so it is impossible to legislate pleasing everyone. This remains an obstacle to the legal and economic integration process and development of the Internal Market. For this reason, the European Court of Justice, as a major player in what is called negative harmonization, has estimated those freedoms through a protectionist interpretation. This protectionist interpretation is that one used by taxpayers as an abusive instrument to elude the compliment of national tax regulations. In this situation and with the aim of obtaining a fair, real and effective tax system, we considered that the best way to deal with these practices is through the use of the doctrine on the prohibition of the abuse of European law adopted by the Court of Justice, allowing Member States to legislate provisions which restrict the exercise of the European freedom. The problem of the use of that theory is its legal nature. It was qualified as a principle of interpretation and not as a general principle of European law, so if we want to use it as anti-abuse provision, it must be codified in the national legal systems as a general anti-abuse rule according to the requirements established by the European Court in the aforementioned doctrine.

La presente trattazione analizza il ruolo delle vicende giuridiche dei rapporti imponibili nella disciplina dell’iva europea e nella sua attuazione nazionale. L’importanza delle vicende giuridiche dei rapporti è cresciuta all'affermarsi un modello di armonizzazione dell’imposta sul valore aggiunto improntato all’elaborazione di un modello d’imposta europeo, con la conseguente riduzione dell’autonomia normativa nazionale e la riconduzione delle fattispecie a categorie giuridiche comuni. Determinato dall’obbligo di rispettare i caratteri fondamentali dell’imposta. La disciplina si è poi evoluta con la sesta direttiva, sino a rappresentare un elemento sistematico, inscindibile dalla disciplina unitaria dettata dalla direttiva in tema di determinazione del corrispettivo quale effetto giuridico di un accordo concluso tra le parti. Ancora, nella messa a sistema dell’imposta con la direttiva rifusioni del 2006 l’assetto sistematico dell’iva europea ha valorizzato le fattispecie autonome corrispondenti a vicende giuridiche rilevanti e ne ha poi previsto l’interpretazione conforme alle previsioni in materia di rettifica della detrazione. Parallelamente a questa evoluzione si è poi sviluppata anche la disciplina italiana delle variazioni, caratterizzata da un’anticipazione nazionale delle stesse fattispecie che sarebbero poi state prese in considerazione con la sesta direttiva e da una peculiare scelta di prevedere l’effettuazione della variazione per il tramite della migliore valorizzazione dello strumento compensativo tipico del peculiare meccanismo applicativo dell’iva. In questo modo l’ordinamento interno ha potuto garantire lo sviluppo della disciplina in modo coerente con l’evoluzione dell’armonizzazione, pur sempre nel limite di un’attuazione e interpretazione con forti limiti casistici. Nella prospettiva di un’evoluzione successiva si valorizza dunque la possibilità di interpretare in senso europeo la disciplina italiana, così da garantire una coerente applicazione dell’art. 90 della direttiva iva, di cui è stato riconosciuto l’effetto diretto con la conseguente necessità di una conformazione delle discipline nazionali in via interpretativa. / Vat is applicable to legal relationship, that means that, whatever happens to the legal relationship considered in order to determinate value added tax, it has to be considered. The European system provide to an autonomous framework, evolved since the first introduction of VAT in 1967. In the present work it is analyzed how this system has been evolved and what are the effects in the national, particularly Italian, legal system.

Many oomycetes species are pathogens of plants, animals and humans; some of them are well studied because they cause significant economic losses in agriculture and acquaculture. The cell wall of oomycetes consists mainly of cellulose, β- (1,3) and β- (1,6)- glucan and in some species a small amount of chitin is also present. The biosynthesis of cellulose in oomycetes is still poorly studied and therefore misunderstood, although it’s the target of some fungicides that inhibit this process, such as carboxylic acid amides. Since 2010, single amino acid exchanges in CesA3 protein conferring CAA resistance in Plasmopara viticola have been identified. In this work, we initially provide the first evidence of the presence of mandipropamid resistant populations of Plasmopara viticola in commercial vineyards in Italy (paper I). We continue by studying the different activity of four CAAs fungicides (benthiavalicarb, dimethomorph, iprovalicarb, mandipropamid) toward P. viticola resistant strains (paper II). The results show that the G1105S mutation affects all four CAAs, but its impact is varied. These results confirm that they are cross resistant, although many gaps in the mode of action are still present. In order to confirm our previous findings, we performed a microscopical base method to assess the sensitivity of four CAAs, and preliminary microscopical data confirmed the different activity toward the CAA-resistant and CAA-sensitive populations (chapter ten). Furthermore, we present a study (chapter eleven) in which we randomly selected samples from paper I, in order to test them using a different approach, simulating a scenario more close to the field. With this test, we were able to confirm the data presented in the paper I.

Plant bacterial diseases are nowadays routinely managed with scheduled treatments based on heavy metal compounds or, in the worst cases, on antibiotics; to overcome the environmental consequences linked to the use of these chemical compounds, such as pollution or selection of antibiotic resistant pathogens, an integrated control management is required. The use of bacterial antagonists, biological agents, plant defence response elicitors or resistant host plant genotypes play an important role in the frame of sustainable agriculture. In this work, the activity of plasma activated water (PAW) and different bioagents aimed to the control of the two bacterial pathogens Xanthomonas vesicatoria and Pseudomonas syringae pv. actinidiae, causal agents of tomato bacterial leaf spot and kiwifruit bacterial canker, respectively, were studied. All these tools were assayed for their direct efficacy and for their ability, as elicitors, to trigger the plant immune system against these two bacterial pathogens. Moreover, a study on several Actinidia sp. accessions was carried out to evaluate their susceptibility against bacterial canker of kiwifruit. PAW resulted unable to direct inhibit X. vesicatoria growth in in vitro assays, however it showed the ability to trigger tomato plant immune system by reducing disease severity up to approx. 38% when tested in three experiments on two tomato genotypes conducted under greenhouse conditions. When tested in in vitro and in vivo experiments against X. vesicatoria and P. syringae pv. actidinidiae, the tested bioagents, based on natural extracted compounds or on different strains of Bacillus sp., showed a direct efficacy against both bacterial pathogens. Moreover, they were also able to elicit the plant defence response by significantly lowering the disease severity on tomato and kiwifruit leaves. In addition, the A. chinensis accession NPK3 resulted the less susceptible to the bacterial canker in comparison to more than 20 accessions tested.

Colletrotrichum acutatum and Botrytis cinerea are among the major fungal pathogens of Fragaria spp. Both pathogens could infect strawberry fruits during the fruit’s early developing stage and remain quiescent until ripening. In strawberry, a fruit ontogenic resistance to pathogen infection was described and correlated with fungal quiescence during the unripe stages of the fruit. Due to the period of fungal quiescence, the management of anthracnose and gray mould diseases becomes more complex as symptoms only manifest in ripe fruits. To identify the underlying component in the ontogenic resistance of strawberry fruits, transcriptomic and metabolomic approaches were used. White and red fruits of strawberry were artificially inoculated with C. acutatum and B. cinerea. Transcriptome profile of B. cinerea infected fruits exhibited a general up-regulation of defense-related genes in white fruits after 24 h of infection. Meanwhile, accumulation of phenolic compounds such as proanthocyanidins, catechins and the ellagitannin casuarictin was also observed in white fruits after 48 h of interacting with C. acutatum and B. cinerea. The acquisition of these findings could provide a benchmark to further investigate the interaction of strawberry against pathogens with latent infection. Hence, a strawberry transformation was performed to study the mechanism of a gene encoding for a mannose-binding lectin protein which was previously identified to be correlated with the resistance of white strawberry fruits to C. acutatum. The regeneration system utilized in the transformation is also discussed.