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La calidad física del suelo puede ser evaluada mediante indicadores estáticos, dinámicos y mecánicos. Los objetivos de esta tesis fueron i) Determinar propiedades del sistema poroso y propiedades hidráulicas del suelo en diferentes momentos del ciclo del cultivo, comparando un sistema de labranza convencional (LC) con el sistema de siembra directa (SD). ii) Evaluar el efecto del tráfico agrícola sobre indicadores de calidad física del suelo en dos sistemas de labranza. iii) Analizar la capacidad de los parámetros resistencia a la penetración (RR) y densidad aparente (DAP), en comparación con infiltración y movimiento del agua en el suelo, para predecir cambios en la calidad física de suelos. Sobre un cultivo de soja sembrado en Chascomús bajo SD y LC, se midió DAP, porosidad total, conductividad hidráulica, porosidad efectiva, distribución de tamaño de poros, índice de conectividad, humedad de suelo, RR y rendimiento del cultivo, en tres momentos diferentes, previo a la siembra, posterior a la siembra y posterior a la cosecha. Se midió en lugares donde hubo huella de la última labor realizada (CH) y en lugares donde no hubo pisada de ningún neumático de la última labor realizada (SH). Se encontró que las propiedades del suelo sufren variaciones temporales generadas por el tráfico agrícola en ambos sistemas de labranza. En LC se dieron las mayores magnitudes de respuesta, como así también en los lugares donde hubo pisada del neumático. No hubo diferencia en el rendimiento del cultivo, a pesar de las diferencias de la calidad física del suelo detectada por los diferentes indicadores evaluados. Se concluyó que la cosecha es la labor que mayor efecto negativo tiene sobre los parámetros físicos, y que tanto la labranza convencional como la siembra directa generan condiciones físicas del suelo que limitan el rendimiento de los cultivos., Facultad de Ciencias Agrarias y Forestales

This poster was published in the LV annual SAIB meeting (2019). Salta - Argentina

Polyamines (PAs) are natural aliphatic amines involved in many physiological processes in almost all living organisms, including responses to abiotic stresses and microbial interactions. This review presents the profuse evidence that relates changes in polyamines levels during responses to biotic and abiotic stresses in model and cultivable species within Leguminosae, and examines their potential roles in the functioning of symbiotic interactions with nitrogen fixing bacteria and arbuscular mycorrhizae. The family Leguminosae constitutes an economically and ecologically key botanical group for humans, being also regarded as the most important protein source for livestock. The ability of legumes to establish symbiotic interactions with nitrogen fixing bacteria and arbuscular mycorrhizae fungi, gives to some legume species that are able to exploit their molecular machinery “pioneer” attributes, with better competition in nutrient-poor soils and higher adaptation to restricted environments. However, many legume crops may be affected by climate change-derived environmental stresses, whereby maintaining their yields safe from adverse environmental conditions is probably one of the biggest challenge facing modern agriculture. Therefore, the obtaining of vigorous genotypes with higher tolerance to abiotic and biotic stressors has turned an increasingly important biotechnological target. At this scenario, PAs can play an important role, and genetic manipulation of crop plants with genes encoding polyamine PA biosynthetic pathway enzymes is envisioned as a strategy to achieve plants with improved stress tolerance and symbiotic performance. As linking plant physiological behavior with "big data" available in "omics" is an essential step to improve our understanding of legumes responses to global change, we also examined integrative MultiOmics approaches available to decrypt the interface legumes-PAs-abiotic and biotic stress or interactions. These approaches are expected to accelerate the identification of stress tolerant phenotypes and the design of new biotechnological strategies to increase their yield and adaptation to marginal environments, making a better use of available plant genetic resources.

Many endophytic bacteria colonize host tissues internally without causing damage or eliciting disease symptoms. Some of them also promote plant growth. Previously, we obtained a collection of bacterial endophytes from leaves of field-grown tomato and identified strains capable to systemically protect this plant against B. cinerea infection. In the present work we used the model plant A. thaliana to analyze the mechanisms involved in the induction of systemic resistance to B. cinerea by one of these strains, Pantoea eucalypti NT6 (PeNT6). In order to evaluate if PeNT6 triggers induced systemic resistance (ISR) in A. thaliana, plants were soil-inoculated with this bacterium and challenged by leaf inoculation with B. cinerea four weeks later. PeNT6 inoculation reduced (30-60%) the size of necrotic lesions caused by B. cinerea. Inoculation with PeNT6 had no effect on the expression of the defense-related genes PR1, PDF1.2, MPK3 and WRKY33. However, plants inoculated with PeNT6 and further challenged with B. cinerea exhibited higher levels of MPK3 and WRKY33 expression than those plants challenged with B. cinerea without previous inoculation with the bacterium. NT6 was unable to trigger ISR in A. thaliana mutants affected in defense signaling pathways mediated by jasmonic acid (coi1), ethylene (ein2) and salicylic acid (sid2). However, the npr1 mutant showed an ISR similar to the wild type. Mutants in MPK3 and MPK6 showed a differential response. While the mpk3 mutant showed no induction of resistance, the mpk6 showed a similar level of ISR to wild type plants. ISR triggered by PeNT6 also involved priming of callose deposition upon Botrytis infection. Finally, the use of a GFP-labeled B. cinerea strain allowed us to determine that in planta germination of fungal conidia was retarded in NT6-inoculated plants. Results hereby presented demonstrate that P. eucalypti triggers ISR to B. cinerea by priming specific components of the defense machinery, such as the kinase MPK3 and the transcription factor WRKY33. ISR triggered by NT6 was also found to depend on jasmonic acid, ethylene and salicylic acid signaling pathways, but did not depend on the regulatory protein NPR1. The kinase MPK3 was also found to play a key role in the onset of ISR by PeNT6. These findings contribute to understand the mechanisms underlying ISR to B. cinerea provided by plant inoculation with beneficial bacteria with the potential to be used as biological control agents.

Dottorato in Scienze e Ingegneria dell’Ambiente, delle Costruzioni e dell’Energia. Ciclo XXXI Università della Calabria

La ricerca cerca di mettere in luce il rapporto che sussiste tra il fenomeno della dismissione e le modalità proprie della trasformazione e di modificazione ciclica delle gerarchie e degli spazi urbani, facendo emergere alcuni temi (capitale sociale nella fabbrica post-fordista, rioccupazione delle aree, condivisione della trasformazione, cooperazione e partecipazione) che manifestano l'attualità di alcune problematiche relative al tema della ricerca e alle dinamiche di trasformazione della città contemporanea. Gli spazi della dismissione rappresentano contesti che, rispetto all’omologazione del territorio circostante, presentano dei tratti di riconoscibilità, caratteri di un insieme identificabile dalla permanenza della memoria storica dei luoghi e dalla presenza di qualità differenziali rispetto al loro contesto. Dunque, il progetto delle aree dismesse si muove tra la permanenza di riconoscibilità, identità e conformazione specifica, e la condizione della trasformazione, con le ragioni di modificazione e di progressione del nuovo, che in esse si manifesta come condizione particolare della perdita d'uso. Stabilita questa dialettica tra permanenza e trasformazione, è stata condotta una selezione di casi-studio, a loro volta suddivisi in diversi atteggiamenti rispetto agli interventi, da cui è emersa l'impossibilità di definire un modello univoco di progetto, ma da cui è stata evinta una sostanziale convergenza verso un progetto aperto capace di accogliere al suo interno il confronto tra la permanenza ed il cambiamento, nell'ottica di costruire nuove relazioni, identità e differenze, considerate nuclei essenziali del progetto di trasformazione nel contesto contemporaneo. Tali aree sembrano oggi sempre più finalizzate alla realizzazione di processi di sviluppo socio-economico, legati alla loro specifica dimensione ex-industriale, che fungono da vero e proprio motore di trasformazione innovativa. Questo processo di riconnessione è stato definito rioccupazione di un’area industriale dismessa e interpretato come conseguimento di obiettivi sociali, ottenuti attraverso processi di forte natura partecipativa, capaci di raggiungere l’equilibrio tra interessi privati e collettività, di garantire la qualità edilizia ed ambientale negli interventi sulle aree industriali dismesse. La fabbrica, perso il significato e connotazione stabile di luogo di trasformazioni e produzione delle merci, diventa luogo della memoria, luogo simbolo di valori, luogo di sperimentazione di nuove progettualità Dottorato Internazionale in Architettura ed Urbanistica QUOD - The Quality of Design, III ciclo, a.a.2010 Università della Calabria

In architectural design field, the interpretation of “sound” parameter evokes cultural and conceptual features that open towards new quality of architecture. The sound, having immaterial and incorporeal implications, is a physical presence in every built space. The sound dimension in architecture suggests the idea of space more livable and human, opposed to the repeated and “silent” images proposed by the media system of popular magazines or of internet pages. The sound invites us to enter the architectural space even to “listen” its intimate qualities. This thesis aims to illustrate how the sound is a contemporary “code” for architectural project that reveals innovative qualities of design. Furthermore the research focus on a comparative study of projectual case studies related to the “sound effect” in order to reveal as a consciousness of this descriptive tool (sound effect) can become a key-theme of project. A similar method of comparison is applied to the spaces of proximity, between outdoor spaces and indoor spaces. The space of proximity is intended as a “sample-space” to verify this comparative approach. These concepts, held through the critical comparison of a series of case studies, reveal the integration of sound parameter as a material both of architectural and urban project. The examples are divided into categories in reason of the distinction between sound and noise and different scales. The first, concerns how the presence of different kind of noise becoming a way to for modelling the architectural project, in big and medium scales. The second one reveals, in the smaller scale of building, how the project uses traditional control of volumes, dimensions and materials to create “sound effects” as components of built space. The other one category focuses on the sound as an artistic component of space through the use of mechanical or electrical installation. The result is that both sound and noise can be considered as aesthetic and generative component of project. The work translates the analytic language of sounds design into a graphicism that shows the skills of project in controlling sound components. A series of “Lebels” and “Sound Maps” are created to facilitate a reading of case studies in relation to the sound effects they produce. This to extrapolate recurring attitudes and design conditions that demonstrate the integration of sound in architectural project. A particular experimentation is leaded on the space of proximity, with the production of schemes that simplify and describe the space between indoor and outdoor and their particular sound conditions. Dottorato di ricerca in International PhD architecture and urbanism, Ciclo III, a.a. 2008-2009 Università della calabria

The role of polyamine (PA) metabolism in tobacco (Nicotiana tabacum) defense against pathogens with contrasting pathogenic strategies was evaluated. Infection by the necrotrophic fungus Sclerotinia sclerotiorum resulted in increased arginine decarboxylase expression and activity in host tissues, as well as putrescine and spermine accumulation in leaf apoplast. Enhancement of leaf PA levels, either by using transgenic plants or infiltration with exogenous PAs, led to increased necrosis due to infection by S. sclerotiorum. Specific inhibition of diamine and PA oxidases attenuated the PA-induced enhancement of leaf necrosis during fungal infection. When tobacco responses to infection by the biotrophic bacterium Pseudomonas viridiflava were investigated, an increase of apoplastic spermine levels was detected. Enhancement of host PA levels by the above-described experimental approaches strongly decreased in planta bacterial growth, an effect that was blocked by a PA oxidase inhibitor. It can be concluded that accumulation and further oxidation of free PAs in the leaf apoplast of tobacco plants occurs in a similar, although not identical way during tobacco defense against infection by microorganisms with contrasting pathogenesis strategies. This response affects the pathogen's ability to colonize host tissues and results are detrimental for plant defense against necrotrophic pathogens that feed on necrotic tissue; on the contrary, this response plays a beneficial role in defense against biotrophic pathogens that depend on living tissue for successful host colonization. Thus, apoplastic PAs play important roles in plant-pathogen interactions, and modulation of host PA levels, particularly in the leaf apoplast, may lead to significant changes in host susceptibility to different kinds of pathogens.

The structure of fructose-1,6-bisphosphate aldolase fromDrosophila melanogaster has been determined by X-ray diffraction at 2.5A˚resolution. The insect enzyme crystallizes in space groupP212121 with lattice constantsa=86.60,b=116.80,c=151.58A˚. Molecular replacement with rabbit muscle aldolase as a search model has been employed to solve the structure. To improve the initial phases real space averaging, including phase extension from 4.0 to 2.5A˚, has been applied. Refinement of the atomic positions by molecular dynamics resulted in a crystallographicR-factor of 0.214. The tertiary structure resembles in most parts that of the vertebrate aldolase from rabbit muscle. Significant differences were found in surface loops and the N- and C-terminal regions of the protein. Here we present the first aldolase structure where the functionally important C-terminal arm is described completely.