Risposte di resistenza a batteri fitopatogeni di importanti specie coltivate indotte da molecole segnale di diversa natura

A modern management of crop protection should be based on integrated control programmes, including the use of environmentally safe products. Antagonistic/beneficial bacteria and resistance inducers may have a great potential in the prophylaxis of diseases caused by common and quarantine pathogens. This work was carried out to confirm the ability of the known strain IPV-BO G19 (Pseudomonas fluorescens) against fire blight (Erwinia amylovora), as well as to evaluate their efficacy against southern bacterial wilt of tomato (Ralstonia solanacearum) and grapevine crown gall (Agrobacterium vitis). A virulent strain of R. solanacearum race 3 was inhibited by the antagonist on plate. When the pathogen was inoculated 48 h after their application to the root apparatus of tomato plants grown in a climatic chamber, bacterial wilt progression rate was clearly reduced. Moreover the defence response evoked by IPV-BO G19 was studied in tomato plants by monitoring the transcription of genes codifying for three PRs as PR-1a, PR-4, PR-5 and for an intracellular chitinase using multiplex RT-PCR and Real Time RT-PCR. In two field trials during 2005 and 2006, the strain IPV-BO G19 was compared with biofungicides and some abiotic elicitors to protect actively growing shoots of pear scions against fire blight. In both trials, IPV-BO G19 plus Na-alginate gave a high level of protection, three weeks after wound inoculation with E. amylovora. In pear leaf tissues treated with the antagonistic strain IPV-BO G19, catalase, superoxyde dismutase and peroxidise activity was evaluated as markers of induced resistance. The IPV-BO G19 strain was compared with other bioagents and resistance inducers to prevent grapevine crown gall under glasshouse and vineyard conditions.

Studies on biotic and abiotic elicitors inducing defense responses in tomato

Tomato (Lycopersicon esculentum Mill., Solanum lycopersicon L.) is one of the most popular vegetable throughout the world, and the importance of its cultivation is threatened by a wide array of pathogens. In the last twenty years this plant has been successfully used as a model plant to investigate the induction of defense pathways after exposure to fungal, bacterial and abiotic molecules, showing triggering of different mechanisms of resistance. Understanding these mechanisms in order to improve crop protection is a main goal for Plant Pathology. The aim of this study was to search for general or race-specific molecules able to determine in Solanum lycopersicon immune responses attributable to the main systems of plant defense: non-host, host-specific and induced resistance. Exopolysaccharides extracted by three fungal species (Aureobasidium pullulans, Cryphonectria parasitica and Epicoccum purpurascens), were able to induce transcription of pathogenesis-related (PR) proteins and accumulation of enzymes related to defense in tomato plants cv Money Maker,using the chemical inducer Bion® as a positive control. During the thesis, several Pseudomonas spp. strains were also isolated and tested for their antimicrobial activity and ability to produce antibiotics. Using as a positive control jasmonic acid, one of the selected strain was shown to induce a form of systemic resistance in tomato. Transcription of PRs and reduction of disease severity against the leaf pathogen Pseduomonas syringae pv. tomato was determined in tomato plants cv Money Maker and cv Perfect Peel, ensuring no direct contact between the selected rhizobacteria and the aerial part of the plant. To conclude this work, race-specific resistance of tomato against the leaf mold Cladosporium fulvum is also deepened, describing the project followed at the Phytopathology Laboratory of Wageningen (NL) in 2007, dealing with localization of a specific R-Avr interaction in transfected tomato protoplast cultures through fluorescence microscopy.

Monitoring Complex Processes to Verify System Conformance: A Declarative Rule-Based Framework

Over the last 60 years, computers and software have favoured incredible advancements in every field. Nowadays, however, these systems are so complicated that it is difficult – if not challenging – to understand whether they meet some requirement or are able to show some desired behaviour or property. This dissertation introduces a Just-In-Time (JIT) a posteriori approach to perform the conformance check to identify any deviation from the desired behaviour as soon as possible, and possibly apply some corrections. The declarative framework that implements our approach – entirely developed on the promising open source forward-chaining Production Rule System (PRS) named Drools – consists of three components: 1. a monitoring module based on a novel, efficient implementation of Event Calculus (EC), 2. a general purpose hybrid reasoning module (the first of its genre) merging temporal, semantic, fuzzy and rule-based reasoning, 3. a logic formalism based on the concept of expectations introducing Event-Condition-Expectation rules (ECE-rules) to assess the global conformance of a system. The framework is also accompanied by an optional module that provides Probabilistic Inductive Logic Programming (PILP). By shifting the conformance check from after execution to just in time, this approach combines the advantages of many a posteriori and a priori methods proposed in literature. Quite remarkably, if the corrective actions are explicitly given, the reactive nature of this methodology allows to reconcile any deviations from the desired behaviour as soon as it is detected. In conclusion, the proposed methodology brings some advancements to solve the problem of the conformance checking, helping to fill the gap between humans and the increasingly complex technology.

La ville picaresque

Cet extrait (le début du projet) peut être essentiellement considéré comme un travail de synthèse, de traduction et d’argumentation concernant un des textes de référence parmi les plus importants au sujet de la littérature picaresque : “La literatura picaresca desde la historia social” écrit par Jose Antonio Maravall. Mon but en développant ce projet était de me focaliser sur les idées principales contenues dans ce volume et en particulier sur la relation existante entre la littérature picaresque et le concept de ville, en termes urbanistiques. Je tiens à souligner le fait que ce travail a été longuement approfondi dans mes nombreuses activités d’étude et de recherche et en me référant, volontairement, au texte lui-même. La raison fondamentale de mon désir de rester près du texte se justifie par le fait que je venais de commence ce qui seraient mes futures activités de recherche de doctorat. J’ai utilisé ces idées à propos de la littérature picaresque, idées qui sont aujourd’hui universellement acceptées, afin de m’orienter moi-même dans ce genre littéraire. Les autres idées que j’ai étudiées et décrites au cours de mes activités de recherche successives sont plus personnelles, car j’avais eu l’occasion de les analyser auparavant. Ce travail n’inclut pas seulement des activités de recherche , mais il s’est agi aussi d’un projet de traduction puisque j’ai dû traduire de l’espagnol(texte original) en italien, pour ensuite concevoir et puis rédiger ma synthèse et mon argumentation en langue française. En conclusion, je peux affirmer que j’ai été capable de construire de solides bases pour élaborer et planifier ma thèse de Doctorat, avec les typiques thèmes de la littérature picaresque, pour exemple la recherche de la nourriture dans la ville.

Giardini per rivivere: orticoltura e giardinaggio a fini terapeutici in contesti sanitari

Questa tesi riassume il lavoro di ricerca da me effettuato per studiare i meccanismi della relazione uomo - pianta su cui si basa l’orticoltura terapeutica, le sue modalità di attuazione e le risposte dei pazienti al lavoro in giardino. La ricerca si è svolta in due diversi giardini terapeutici con pazienti adulti con varie tipologie di disabilità fisica o psichica. Partendo dalla analisi delle basi teoriche su cui si fonda l’ortoterapia, l’obiettivo era di capire come creare le condizioni migliori per ottenere i massimi benefici dall’uso dell’orticoltura e del giardinaggio per il benessere delle persone. Due elementi sono apparsi fondamentali per il raggiungimento degli obiettivi terapeutici: il primo è lo stretto legame esistente tra la forma del giardino e delle piante e la sua funzione terapeutica; il secondo sta nella necessità di creare nel paziente una connessione profonda con il giardino e il lavoro con le piante è risultato essere un fattore determinante per farlo. Utilizzando questionari e osservazioni degli utenti, sono stati raccolti ed elaborati dati relativi al benessere dei pazienti durante e dopo le attività in giardino e si è cercato di trovare un indice, individuato poi nella variazione di percezione del pollice verde, che potesse essere utilizzato per esprimere la soddisfazione del paziente. Infine si è cercato di capire come potesse variare la capacità ristorativa del giardino, in funzione della frequenza di visita e dell’attività che vi si svolgeva, attraverso la somministrazione della versione italiana della scala PRS a chi era impegnato nelle attività di orticoltura e giardinaggio, a chi passeggiava nel parco e a chi invece non lo frequentava regolarmente ma lo conosceva bene: è risultato che le tre modalità di fruizione del giardino davano ai fruitori un potenziale rigenerativo diverso e significativamente più alto per chi metteva le mani nella terra.