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Quan pensem en organismes simbiòtics, normalment ens venen al cap els líquens, que estan constituïts per una alga i un fong. També les abelles i les plantes amb flor, o els peixos pallasso i les anemones de mar són exemples comuns de simbiosi. Al plàncton també en trobem uns quants exemples, encara que segurament menys coneguts. Per exemple, els coralls formen una relació simbiòtica amb una classe d’algues, les zooxantel·les, del gènere Symbiodinium, que viuen dins d’ells, perquè el corall i les algues es proporcionen aliment mútuament. També hi ha casos de simbiosi en els quals ambdues espècies implicades formen part del plàncton. Aquest és el cas del ciliat Eutintinnus sp. i la diatomea Chaetoceros (normalment Chaetoceros tetrastichon o C. dadayi). El ciliat es protegeix amagat dins les llargues espines del Chaetoceros i aquest, al seu torn, pot viatjar gratis i pot nodrir-se de les sals minerals excretades pel protozou (Fig. 1). El grau d’associació és tal, que és molt rar trobar ambdues espècies soles

[ES] Un proyecto de Biomimética en el que nuestro cliente Sympany (Países Bajos) colabora con una compañía de supermercados a domicilio llamada Picnic. Los usuarios recolectan y clasifican su ropa en casa y lo registran en una aplicación que hemos desarrollado (obteniendo un código QR). Estos piden comida en Picnic y el repartidor recolecta estas bolsas de ropa, intercambiando los paquetes de comida por los de ropa en el interior del camión de Picnic. Este hará la donación oficial al escanear el Código QR (de nuestra aplicación), tras esto, el usuario obtiene puntos. Estos puntos serán canjeables en una de las tiendas de segunda mano colaboradoras de Picnic, creando de esta forma una cadena textil completamente circular en Países Bajos. Esta colaboración está inspirada en simbiosis de organismos de la naturaleza (previamente estudiadas). --------- Un projecte de Biomimética en el que el nostre client Sympany (Països Baixos) col·labora amb una companyia de supermercats a domicili anomenada Picnic. Els usuaris recol·lecten i classifiquen la seua roba a casa i ho registren en una aplicació que hem desenrotllat (obtenint un codi QR). Estos demanen menjar en Picnic i el repartidor recol·lecta estes bosses de roba, intercanviant els paquets de menjar per això de roba en l'interior del camió de Picnic. Este farà la donació oficial a l'escanejar el Codi QR (de la nostra aplicació) , després d'açò, l'usuari obté punts. Estos punts seran canviables en una de les botigues de segona mà col·laboradores de Picnic, creant d'esta manera una cadena tèxtil completament circular en Països Baixos. Esta col·laboració està inspirada en simbiosi d'organismes de la naturalesa (prèviament estudiades)., [EN] A Biomimicry project in which our client Sympany (The Netherlands) collab with a ¿door to door¿ supermarket company called Picnic. Users will collect and sort their own clothes at home and register this in the app we will develop (obtaining a QR code). They will order for food at Picnic and the delivery man will collect these clothes, swapping food for clothes packs inside the Picnic truck. He will make official the donation by scanning the QR code (from our app) and the user will obtain some points. These points will be exchanged in second-hand shops which collab with Sympany, creating a completely textile circular chain in The Netherlands. This collaboration is inspired in (previously studied) symbiosis in nature organisms.

L���origine della pandemia da COVID-19 �� da attribuire alla devastazione e distruzione del pianeta causata dai nostri esasperati consumi e stili di vita. Infatti �� dalla rivoluzione industriale in poi che noi, sapiens sapiens, abbiamo devastato pi�� dei 2/3 della superfice terrestre per processi di industrializzazione, urbanizzazione e produzione agricola. Non solo, abbiamo deforestato l���equivalente della superficie del continente africano per l���allevamento intensivo di bovini e la produzione di carne rossa.Tutto ci�� ha ampliato a dismisura disuguaglianze ed ingiustizie sociali ed ambientali. Il rapporto di Sir Partha Dasgupta (l���economia della biodiversit��) e lo studio dell���opera di Gilbert Simodon, che qui commentiamo, sono un prezioso aiuto per responsabilizzarci sulla gravit�� della ���questione ecologica���. Ci stiamo comportando da buoni antenati? E, soprattutto, che tipo di pianeta lasceremo alle generazioni a venire?, N��ema, N. 12 (2021): Filosofia dell'ecologia: eco-poietica ed eco-paidetica

Symbiosis is the living together of dissimilar organisms [1,2]. As such, symbiotic relationships can range from antagonist (parasitic) to mutualistic and can vary along this continuum within and between species in space and time. Microbial symbioses encompass a wide array of players (e.g., bacteria, fungi, and small eukaryotes) and are an integral part of organismal life, contributing to phenotypes at all levels of biological organization, from molecules to ecosystems. There has been an explosion of microbiological research on symbiosis emerging from the omics revolution, which has made many previously intractable symbioses available for dissection. Current research ranges from unraveling the biochemical interactions among symbiont partners to uncovering the incredible ecological diversity and dynamics of microbial communities and host associations. Host-microbes engage in extensive and complex cross-kingdom molecular dialogue, where symbionts can modulate their reciprocal gene expression patterns, complement metabolic pathways, and combine genetic information through DNA exchange, in some cases becoming sufficiently integrated through coinheritance to be considered as an evolutionary unit of selection. This extensive genetic and biochemical interplay has enormous implications in the emergence of novel traits and the overall diversification of life.

[eng] The symbiotic lifestyle represents a fundamental contribution to the diversity of marine ecosystems. Sponges are ideal models to study symbiotic relationships from evolutionary and ecological points of view since they are the most ancient metazoans on Earth, are ubiquitous in the marine benthos, and establish complex symbiosis with both prokaryotes and animals, which in turn harbour their own bacterial communities. In this thesis, we aim to go deeper into the mechanisms by which sponges establish symbiotic associations with members of the three domains of life, combining taxonomical, ecological, and molecular approaches. We study how sponges acquire their symbiotic microbes and whether these microbes contribute to shape the ecological distribution of their hosts. Moreover, we use the sponge-polychaete relationship as an example of multi-partner symbiosis and study the eukaryotic association from the microbial perspective. Finally, we focus on the less studied domain of life, the archaea, to gain insights into the composition and stability of these symbionts in sponges. To assess these goals, we characterized the sponge assemblages in two contrasting environments (well-preserved and impacted) of Nha Trang Bay (Vietnam) and selected the most abundant species for the study of their microbiomes. Additionally, four sponge species harbouring thousands of polychaetes were sampled to analyse the relationships sponge-microbes-polychaetes. Sponges and polychaetes were identified and their respective microbiones and the seawater bacterial communities were analysed by high-throughput sequencing of the 16S rRNA gene (V4 region). We first describe and illustrate the sponges collected to facilitate further taxonomic and faunistic studies in the area. Our samples belonged to 60 species (9 orders, 22 families, and 36 genera) of demosponges. A total of 24 species were added to the already known sponge fauna of Vietnam, from which, 11 species likely represent new species to science. The described species represent an increase of 8 % in the already known sponge list of Vietnam. Our results show that sponge assemblages were more diverse and rich in the well-preserved environments, being dominated by Neofibularia sp. and Aaptos suberitoides in the reefs, and by Monanchora unguiculata, Antho (Antho) sp., and Amphimedon sulcata in rocky habitats. On the other hand, impacted coral reefs were mainly dominated by two abundant species: Clathria reinwardti and Amphimedon paraviridis. Similar ecological metrics were shown by the sponge microbiomes according to the type of habitat, being more diverse in the well-preserved environments. Morever, the sponge microbiomes of the sponge assemblages from the impacted habitats showed higher intra-species dispersion and lower core size (shared ZOTUs across species replicates) than microbiomes of sponges from the well-preserved environments. In this sense, we propose that the Anna Karenina concept, which states that intraspecific variability is higher in dysbiotic than in healthy individuals, can also be applied at the community level for the study sponge assemblages. In our study sponges, bacterial communities were highly stable regardless of the environment, whereas some of their associated polychaetes varied depending on the sampling location. Environmental resilience to different habitat conditions was certainly true for bacterial communities of A. sulcata, the solely species that was found abundant in the two contrasting habitats explored. Moreover, the high overlap in bacteria composition between sponges and seawater suggest microsymbiont acquisition from the environment. In a similar manner, polychaetes were also able to specifically select and enrich some bacteria from their food sponge. Overall, most sequences were shared between biotypes, but at differential abundances, leading to highly specific and stable invertebrate microbiomes, acquired from the environment. Our results support the tenet “Everything is everywhere, but the environment selects”., [cat] La vida en simbiosi representa una contribució fonamental a la diversitat dels ecosistemes marins. Les esponges són models ideals per l’estudi de les relacions simbiòtiques des del punt de vista evolutiu i ecològic, ja que són els metazous més antics de la Terra, són ubiqüistes al bentos marí, i estableixen simbiosis complexes amb procariotes i animals, que al seu torn, contenen les seves pròpies comunitats bacterianes. En aquesta tesis, volem aprofundir en els mecanismes pels quals les esponges estableixen associacions amb membres dels tres dominis de vida, combinant eines taxonòmiques, ecològiques i moleculars. Estudiem com les esponges adquireixen els seus microbis simbionts i com aquests microbis contribueixen a modelar la distribució ecològica de les esponges. A més, utilitzem la relació esponja-poliquet com a exemple de simbiosis multi-organisme i estudiem les associacions eucariotes des de un punt de vista microbià. Finalment, ens centrem en el domini de vida menys estudiat, les arqueas, per aprofundir en la composició i estabilitat d’aquests simbionts en esponges. Per assolir aquests objectius, vam caracteritzar els grups d’esponges de dos ambients diferenciats (impactat i ben preservat) de la badia de Nha Trang (Vietnam), i vam seleccionar les espècies més abundants per l’estudi del seu microbioma. Addicionalment, vam mostrejar quatre espècies d’esponges que contenien milers de poliquets per l’anàlisi de les relacions esponja-microbis-poliquets. Els nostres resultats mostren que les comunitats d’esponges eren més riques i diverses en els ambients ben preservats, i els seus microbiomes mostraven variables ecològiques similars, en els dos tipus d’ambients. La majoria de simbiosis estudiades mostraven una gran especificitat i estabilitat, independentment de l’ambient on vivia l’esponja. El gran solapament entre les bactèries de l’aigua i de l’esponja suggereix que hi ha adquisició microbiana de l’ambient. De forma similar, els poliquets també eren capaços d’adquirir específicament bactèries de les esponges de les quals s’alimentaven. En resum, la majoria de seqüències microbianes eren compartides entre els tres habitats estudiats (aigua/esponge/poliquet), però a diferents abundàncies, donant lloc a microbiomes específics i estables adquirits de l’ambient en els dos grups d’invertebrats estudiats .

[eng] Symbiosis research is a growing field in contemporary biology. Current advances in modelling and experimental techniques have made possible to develop new ways of studying some multispecies symbiotic systems whose study had been mostly ignored in the past. Some of these new modelling and experimental techniques rely on the use of sophisticated mathematical tools (such as network analysis) that can only be used if the system is conceived holistically. One of the main consequences of this approach is that de-composition becomes an impossible task: if biologists want to understand how some multispecies symbiotic systems work, how they behave, or how they evolve, they need to study the system holistically, rather than study how each of the parts of the system relates to each other. This type of research seems to question the dominant tradition in contemporary philosophy of science and biology, namely: new-mechanism. According to the principles of new-mechanistic philosophy, biological systems need to be de- composed in their component elements to properly understand how they work, and in order to unveil the causal connections among the components. The purpose of this doctoral thesis is to understand how contemporary symbiosis research questions some of the core philosophical thesis that underlie new-mechanistic philosophy. To do so, the thesis will rely on two philosophical methods: (1) analysis of scientific practise; (2) conceptual analysis. By applying these two methods to contemporary symbiosis research, the thesis gives rise to three papers in specialized journals, added as annexes. The key original contribution of the doctoral dissertation is that contemporary symbiosis research relies on the use of certain mathematical methods that are only applicable if the system is studied holistically, and thus entail a form of non-causal-mechanistic explanation. In the end, several open questions for future research are presented., [spa] La investigación sobre la simbiosis es un campo en crecimiento en la biología contemporánea. Los avances actuales en el modelado y las técnicas experimentales han permitido desarrollar nuevas maneras de estudiar algunos sistemas simbióticos de múltiples especies cuyo estudio había sido ignorado en el pasado. Algunas de estas nuevas técnicas experimentales y de modelado se basan en el uso de herramientas matemáticas sofisticadas (como el análisis de redes) que solo se pueden emplear si el sistema se concibe de manera holística. Una de las principales consecuencias de este enfoque es que la descomposición del sistema en partes se vuelve una tarea imposible: si los biólogos quieren comprender cómo funcionan algunos sistemas simbióticos de múltiples especies, cómo se comportan o cómo evolucionan, deben estudiar el sistema de manera holística, en lugar de estudiar cómo cada una de las partes del sistema se relaciona entre sí. Este tipo de investigación parece cuestionar la tradición dominante en la filosofía contemporánea de la ciencia y la biología, a saber: el nuevo mecanismo. De acuerdo con los principios de la filosofía del nuevo mecanicismo, los sistemas biológicos deben descomponerse en sus elementos componentes para comprender adecuadamente cómo funcionan y para descubrir las conexiones causales entre los mismos. El propósito de esta tesis doctoral es comprender cómo la investigación contemporánea sobre simbiosis cuestiona algunas de las tesis filosóficas centrales que subyacen a la filosofía del nuevo mecanismo. Para hacerlo, la tesis se basará en dos métodos filosóficos: (1) análisis de la práctica científica; (2) análisis conceptual. Al aplicar estos dos métodos a la investigación contemporánea sobre simbiosis, la tesis da lugar a tres artículos en revistas especializadas, que se agregan como anexos. La contribución original clave de la disertación doctoral es que la investigación contemporánea sobre la simbiosis se basa en el uso de ciertos métodos matemáticos que solo son aplicables si el sistema se estudia de manera holística y, por lo tanto, conlleva una forma de explicación no mecanicista y no causal. Al final, se presentan varias preguntas abiertas para futuras investigaciones.

Este artículo contiene 13 páginas, 6 figuras, 3 tablas., All multicellular organisms, including ascidians, host diverse microbial communities that are essential for their evolution. The global invader Didemnum vexillum is a colonial species native to Japan with two main genetic clades, A (the only invasive) and B, which provides a unique opportunity to assess if the microbiome remains stable in the colonization process or shifts according to local environment. We have analyzed, using 16S amplicon sequencing, the microbiome of 65 D. vexillum colonies from 13 populations worldwide including the two clades in the native area, plus samples from a congeneric species and seawater from one of the localities. We found 3,525 zeroradius operational taxonomic units (ZOTUs) in D. vexillum, belonging to 36 bacterial and 3 archaeal phyla. The microbiome of this species had a markedly different composition from surrounding seawater and from the congeneric species. For the globally invasive clade A, we found 3,154 ZOTUs, and 8 of them were present in all colonies, constituting a core microbiome with high abundance (69.57% of the total reads) but low diversity (0.25% of the total number of ZOTUs). The variable component was quantitatively much less important but comprised a highly diverse assemblage. In a multiple regression model, global microbiome structure correlated with differences in temperature range across localities and also with geographic distances, pointing to horizontal acquisition ofthesymbionts.However,theascidianmayhaveastrongcapacitytoselectandenrich itsmicrobiome,aswefoundthatthemostabundantZOTUsfromtunicsampleshadlow abundance in seawater samples from the same locality. The microbiome structure also correlated with the genetic distances between colonies obtained in a previous genomewide analysis, suggesting some potential for vertical transmission. In geographically restrictedcomparisons,temperatureandgeneticmakeup,butnotgeography,explained microbiome structure. The combination of a quantitatively dominant core component and a highly diverse variable fraction in the microbiome of D. vexillum can contribute to the success of this global invader in different environments., This research was funded by the projects CHALLENGEN and PopCOmics (CTM2013-48163 and CTM2017-88080, MCIU/AEI/FEDER/UE)fromtheSpanishGovernment.MCwas fundedbyapredoctoralFPIcontractoftheSpanishGovernment. We acknowledge support of the publication fee by the CSIC Open Access Publication Support Initiative through its Unit of Information Resources for Research (URICI). This is a contribution from the Consolidated Research Group Benthic BiologyandEcologySGR2017-1120(CatalanGovernment).

Capitolo dedicato ai funghi micorrizici, alle loro interazioni con la pianta ospite e alle loro potenzialità applicative.

L'utopia è una delle forme privilegiate di immaginazione dell'impossibile e uno dei temi centrali della produzione letteraria e filosofica di Olaf Stapledon. In Last and First Men egli non si limita a elaborare modelli politico-sociali alternativi ma immagina un cambiamento radicale della natura umana, a partire dalle sue basi biologiche. Lo scopo del presente lavoro è analizzare l'uso metaforico della biologia nella costruzione dell'ideale utopico della comunità autentica emergente dalla successione di diverse specie umane. Attraverso la tecnica del close reading guidata dal modello ermeneutico dell'utopia di Jameson, si mostrerà come concetti biologici e metafore organiche investano trasversalmente i livelli allegorici del corpo, del tempo e della collettività. L'attenzione sarà concentrata sul tema della telepatia. In quanto dispositivo simbolico di massima apertura all'altro, essa costituisce la pietra angolare della comunità autentica. Si mostrerà come tale facoltà si colleghi metaforicamente ai concetti di simbiosi e di simbiogenesi, esplicitamente rappresentati nel testo come meccanismi di speciazione. Il processo evolutivo immaginato da Stapledon, connettendo biologia ed etica, si configura dunque come una contestazione del primato dell'egoismo e della competizione per la sopravvivenza, postulato dal darwinismo sociale, a vantaggio degli ideali comunitari di solidarietà e cooperazione., Between, Vol 9, No 17 (2019): Imagining the Impossible: Crossings of Creativity Between Literature and Science

La reconsideración de la educación arquitectónica a la luz de una nueva realidad que surge de los rápidos cambios que se producen en nuestros entornos sociales, culturales y físicos es ahora imperativa. Para conocer las incompatibilidades de las estructuras educativas existentes con la dinámica actual del cambio, se examinan tres aspectos principales de nuestra educación arquitectónica contemporánea: el sistema de estudios, los contenidos de los estudios y la pedagogía del diseño arquitectónico implementado por las Escuelas de Arquitectura.En cuanto al sistema de estudios, entre otras cuestiones, especulamos sobre la agilidad limitada del sistema para albergar innovaciones, sus concepciones dominantes sobre el perfil del profesor, su forma poco clara de definir el perfil del graduado y la oscura relación entre la academia arquitectónica y la práctica profesional. En cuanto al contenido de los estudios, entre otras cuestiones, especulamos sobre el empobrecimiento de las humanidades en los estudios arquitectónicos que provocó un tecnicismo pasivo que, fascinado por las herramientas digitales, esteriliza la arquitectura de sus valores y significados culturales y humanos.Otras observaciones se refieren a la pedagogía actual y sus reservas sobre el temor a la confusión y la asunción de riesgos, a la rigidez metodológica de la educación basada en lo que está mal y no en lo especulativo, en la actitud hacia ) Simplifican la complejidad, la inclinación pasiva y la docilidad hacia las certezas, la resistencia al cambio, la revisión o la renovación de las prácticas docentes.El trabajo concluye presentando las líneas básicas de las prioridades que la educación arquitectónica tiene que considerar para poder seguir críticamente el nuevo paradigma surgido y impuesto por los nuevos entendimientos filosóficos de nuestro mundo y la consideración de la nueva normalidad que se atribuye a Como una nueva declaración ética que afecta profundamente la contemplación arquitectónica y la práctica. La reconsideració de l'educació arquitectònica a la llum d'una nova realitat que sorgeix dels ràpids canvis que es produeixen en els nostres entorns socials, culturals i físics és ara imperativa. Per conèixer les incompatibilitats de les estructures educatives existents amb la dinàmica actual del canvi, s'examinen tres aspectes principals de la nostra educació arquitectònica contemporània: el sistema d'estudis, els continguts dels estudis i la pedagogia del disseny arquitectònic implementat per les Escoles d'Arquitectura.Pel que fa al sistema d'estudis, entre altres qüestions, especulem sobre l'agilitat limitació sistema per albergar innovacions, les seves concepcions dominants sobre el perfil del professor, la seva forma poc clara de definir el perfil del graduat i la fosca relació entre l'acadèmia arquitectònica i la pràctica professional. Pel que fa al contingut dels estudis, entre altres qüestions, especulem sobre l'empobriment de les humanitats en els estudis arquitectònics que va provocar un tecnicisme passiu que, fascinat per les eines digitals, esterilitza l'arquitectura dels seus valors i significats culturals i humans.Altres observacions es refereixen a la pedagogia actual i les seves reserves sobre la por a la confusió i l'assumpció de riscos, a la rigidesa metodològica de l'educació basada en el que està malament i no en el especulatiu, en l'actitud cap) Simplifiquen la complexitat , la inclinació passiva i la docilitat cap a les certeses, la resistència al canvi, la revisió o la renovació de les pràctiques docents.El treball conclou presentant les línies bàsiques de les prioritats que l'educació arquitectònica ha de considerar per poder seguir el nou paradigma sorgit i imposat pels nous enteniments filosòfics del nostre món i la consideració de la nova normalitat que s'atribueix a Com una nova declaració ètica que afecta profundament la contemplació arquitectònica i la pràctica. The reconsideration of architectural education in light of a new reality emerging from the fast changes occurring in our social, cultural and physical environments is now imperative. In order to divulge the incompatibilities of the existing educational structures with the current dynamics of change, three main aspect of our contemporary architectural education are examined: the system of studies, the contents of studies and the architectural design pedagogy implemented by Schools of Architecture.Concerning the system of studies, amongst other issues we speculate on the limited agility of the system to host innovations, its dominant conceptions about the teacher’s profile, its unclear way to define the profile of the graduate and the obscure relationship between architectural academia and professional practice. As to the content of studies amongst other issues we speculate on the impoverishment of humanities in architectural studies that caused a passive technicality which, fascinated by the digital tools, sterilizes architecture from its cultural and human values and meanings.Further observations concern current pedagogy and its reservations on the fear for mistake-making and risk-taking, on the methodological rigidity of design education founded on what is wrong and on not what could be done on a speculative basis, on the attitude to (over)simplify complexity, on the passive inclination and docility towards certainties, on the resistance to change, revisit or renew teaching practices.The paper concludes by presenting the basic lines of the priorities architectural education has to consider in order to be able to critically follow the new paradigm emerging from and imposed by the new philosophical understandings of our world and the consideration of the new normal that is ascribed to them as a new ethical statement that profoundly affects architectural contemplation and practice.

Here, we report the surprising and, to our knowledge, unique example of horizontal interkingdom transfer of a human opportunistic pathogen (Propionibacterium acnes) to a crop plant (the domesticated grapevine Vitis vinifera L.). Humans, like most organisms, have established a long-lasting cohabitation with a variety of microbes, including pathogens and gut-associated bacteria. Studies which have investigated the dynamics of such associations revealed numerous cases of bacterial host switches from domestic animals to humans. Much less is, however, known about the exchange of microbial symbionts between humans and plants. Fluorescent in situ hybridization localized P. acnes in the bark, in xylem fibers, and, more interestingly, inside pith tissues. Phylogenetic and population genetic analyses suggest that the establishment of the grapevine-associated P. acnes as obligate endophyte is compatible with a recent transfer event, likely during the Neolithic, when grapevine was domesticated.

Il sistema città/territorio, per affrontare le sfide di rigenerazione economica, sociale e ambientale, ha bisogno di un nuovo modello di sviluppo, basato sui processi di simbiosi e di circolarizzazione. La simbiosi costituisce lo strumento per ricostruire e moltiplicare i legami a diversi livelli e, grazie alla densità di relazioni che genera, rende il sistema più resiliente, più efficiente e meno dissipativo; migliorandone la sua capacità rigenerativa. La città, e in particolare la città portuale, rappresenta il contesto da cui partire per mettere in relazione i diversi fattori economici, sociali e culturali, gestire la complessità secondo un approccio sistemico e realizzare visioni di futuro sostenibile. Parole chiave: simbiosi, economia circolare, città portuale, BDC. Bollettino Del Centro Calza Bini, Vol 16, No 2 (2016): Circular Economy and Symbiosis: The Sustainable Regenerative City Model

Els macroinvertebrats aquàtics són hostes d’una àmplia varietat d’endosimbionts aquàtics; entre aquests, els tricomicets (fongs i protozous), que han estat tradicionalment estudiats per micòlegs. El protozou Paramoebidium avitruviense viu associat amb les fases nimfals de Siphonoperla torrentium (Chloroperlidae, Plecoptera). En un estudi de monitoratge realitzat a la riera de Vallforners (Parc Natural del Montseny, Barcelona) es va obtenir un nombre important de tal·lus de P. avitruviense. Aquest fet ha permès fer una revisió i emanació de l’espècie, especialment per a les fases de cist, que anteriorment s’havien confós amb les d’una altra espècie pròxima. També s’aporten dades sobre la primera observació de Smittium (Harpellales, Kickxellomycotina) associat al sistema digestiu de plecòpters., Aquatic macroinvertebrates harbor a broad spectrum of gut endosymbionts, among them trichomycetes species (including fungi and protozoan), which have been traditionally studied by mycologists. The protozoan Paramoebidium avitruviense lives in association with the nymphal stages of Siphonoperla torrentium (Chloroperlidae, Plecoptera). Important quantities of P. avitruviense thalli were obtained during a long-term study performed in Vallforners stream (Montseny Natural Park, Barcelona, Spain), allowing a revision and emendation of the species, particularly regarding the morphology of the cysts, which were previously misidentified. We also document for the first time the presence of Smittium (Harpellales, Kickxellomycotina) within the digestive system of S. torrentium, and provide a discussion for this unusual observation.

The rapid growth in microbiome research, particularly during the last 15 years, has revealed the crucial contributions of microbial communities to numerous physiological functions in animals, including digestion, immunity and reproduction. The permanent coexistence of these various bionts forms the holobiont (namely, the host and its microbiota). This review describes the relationships between xylophagous insects and their microbiota in an attempt to understand the characteristics that have determined bacterial fidelity over generations and throughout evolutionary history. Symbiotic interactions have probably played a central role in the evolutionary success of these insects, allowing their adaptation to unexploited ecological niches that are nutritionally deficient and/or unbalanced. Moreover, insect symbionts have provided the enzymatic capabilities that enable the synthesis of nutrients (carbon and nitrogen sources for the host) from recalcitrant plant polymers (cellulose, hemicellulose, pectin or lignin).

Oxydromus humesi is a strict bivalve endobiont, probably a parasite, living in association with Tellina nymphalis in north of Pointe-Noire (Congo mangrove swamps, West Africa) and Scrobicularia plana (intertidal) and Psammotreta cumana (subtidal) in Cádiz Bay salt marshes (southern Atlantic coast of Iberian Peninsula). The symbiont shows a regular distribution (one, exceptionally two or three symbionts per host, being one male, one female and one small worm) with intraspecific competition and complex host-entering behaviour observed in experimental conditions. This work aims to study the population dynamics of the above-mentioned species hosted by S. plana in Cádiz Bay to increase knowledge on the biology of O. humesi and to contribute to the growing knowledge on symbiotic polychaetes. The population of the symbiont in the intertidal area of Rio San Pedro (Cádiz Bay) seems to reproduce actively through all the year, with a higher number of ripe females in spring and, particularly, in summer. Although S. plana is very abundant in the studied area, with a large amount of specimens having the size most preferred by the symbiont (i.e., from >26 mm to about 36 mm long), the prevalence tends to be very low (usually 85% in the specimens longer than 20 mm) of P. cumana in Río San Pedro mouth, lead us to discuss on the environmental requirements and host-specificity of O. humesi. We suggest that the studied intertidal could be at the limit of the ecological distribution of this symbiont in the Cádiz Bay region. The symbiotic hesionid seems to show a seasonal pattern of prevalence, which may be related with its reproduction (the periods with more ripe females tended to coincide with those of lower prevalence). Taking into account these data, we propose that males undertake reproductive migrations probably to improve the possibilities of fertilization, whilst the females stay throughout the whole life inside the host. The life-cycle of O. humesi remains unknown since the species’ discovery in the coasts of the Republic of Congo. However, our data allow us to suggest that its life span may be of one year, with the adults dying after reproducing

Several insect lineages have evolved mutualistic associations with their symbiotic bacteria. This is the case of some members of Tephritinae, the most specialized subfamily of fruit flies (Diptera: Tephritidae), harboring co-evolved and vertically transmitted bacterial symbionts in their midgut, known as ‘Candidatus Stammerula spp.’. In the tephritid fly Bactrocera oleae, the major olive pest, symbionts are located in the oesophageal bulb, a diverticulum of the fly head, and designated as ‘Candidatus Erwinia dacicola’. This research, based on two main studies, is focused on different aspects of the relationships between species of the family Tephritidae and their nonculturable symbiotic bacteria. The first study investigated the presence of specific symbiotic bacteria in 15 of the 25 described endemic tephritids of the Hawaiian Archipelago, which represent a spectacular example of adaptive radiation, and their molecular relationships with symbionts of non-Hawaiian tephritids. Moreover the concordant evolution between host and symbiont phylogenies was tested. A specific symbiont was detected through PCR assays in all endemic individuals analyzed and it was designated as ‘Candidatus Stammerula trupaneae’ as it was included in Ca. Stammerula spp. monophyletic clade. The phylogeny of the insect host was reconstructed based on two regions of the mitochondrial DNA (16S rDNA and COI-tRNALeu-COII), while the bacterial 16S rRNA was used for the symbiont analysis. Host and symbiont phylogenies were then compared and evaluated for patterns of cophylogeny and strict cospeciation. Topological congruence between Hawaiian Tephritinae and their symbiotic bacteria phylogenies suggests a limited, but significant degree of host-symbiont cospeciation. The character evolution of three host traits, as island location, host lineage, and host tissue attacked, was finally reconstructed based on the symbiont phylogenies under the hypothesis of cospeciation. The second study surveys the genetic variability of the olive fly symbiont, Ca. Erwinia dacicola, together with the patterns of genetic differentiation of B. oleae, over a large area of its geographical distribution, including most regions of the Mediterranean area, plus South Africa, California and Pakistan. Three bacterial haplotypes, showing a significative geographic distribution, were identified and the co-existence of different Ca. E. dacicola haplotypes in a single fly was never found. Our results reveal the presence of three symbiont haplotypes with a significant phylogeographic distribution related to the territory. In the Mediterranean populations only two bacterial lineages (htA and htB), previously recovered in Italian olive fly populations, have been found, showing a significative East-West genetic differentiation. The South African and Californian olive fly populations were represented only by one of these two lineages, respectively htA and htB. Moreover, a new haplotype (htC) was detected exclusively in the Pakistani population. On the other hand, a high degree of mitochondrial genetic variability with a substantial phylogeographic differentiation has been observed in the B. oleae populations analyzed, revealing the presence of 39 insect haplotypes. Symbiont and host haplotypes were then compared and a significant correlation was found suggesting the predominant presence of vertical transmission. Moreover, the bacterial haplotypes distribution seems to be more related to the territory than the numerous insect host haplotypes, representing an useful tool to reconstruct the debated olive fly’s historical origin.

2012/2013 I licheni, una simbiosi mutualistica tra un fungo (il micobionte), generalmente un ascomicete, e una o più popolazioni di alghe e/o cianobatteri (il fotobionte) sono considerati forme di vita estremofile in quanto da disidratati possono resistere a condizioni ambientali molto difficili come elevati irraggiamenti solari, scarsa disponibilità d'acqua e di nutrienti e dosi elevate di inquinanti aerodiffusi. Tali fattori di stress tuttavia inducono una sovrapproduzione a livello cellulare di specie reattive dell'ossigeno (ROS), che se eccede le difese antiossidanti genera stress ossidativo. L'accumulo delle ROS è un fenomeno molto pericoloso perché porta al danneggiamento di importanti macromolecole come lipidi, proteine e DNA ed in casi estremi può condurre anche alla morte cellulare. Sebbene gli effetti dello stress foto-ossidativo nei licheni siano già stati studiati, in questo dottorato di ricerca si è voluto approfondire alcuni aspetti ancora poco chiari relativi alla resistenza dei fotobionti a questo stress e alla resistenza dei licheni allo stress ossidativo indotto dalla presenza di elevate concentrazioni di inquinanti fotochimici come l'ozono (O3). Sul primo filone di ricerca sono stati condotti due studi. Nel primo ci si è focalizzati sugli effetti dello stress foto-ossidativo su parametri fisiologici di vitalità (ChlaF) e di produzione di ROS in un fotobionte lichenico e nella sua controparte lichenizzata. Ciò è stato ottenuto sottoponendo colture axeniche del fotobionte Trebouxia sp. e lobi del lichene Parmotrema perlatum da cui è stato isolato il fotobionte, a diverse combinazioni di umidità relativa e intensità luminose per periodi di tempo crescenti. L'obiettivo di questo studio è stato quello di approfondire le conoscenze sui benefici indotti dalla lichenizzazione nella resistenza al disseccamento e al concomitante stress foto-ossidativo. Il secondo studio invece, strettamente connesso al primo, è focalizzato sulla variazione di espressione genica dell'intero trascrittoma del fotobionte Trebouxia gelatinosa, isolato dal lichene Flavoparmelia caperata (L.) Hale, indotta da eventi di disidratazione e reidratazione. Con questo studio si è voluto individuare ed analizzare i meccanismi molecolari alla base della tolleranza di questo organismo al disseccamento e al concomitante stress fotoossidativo. Sul secondo filone di ricerca invece è stato condotto uno studio sulle risposte fisiologiche, citologiche e biochimiche del lichene Flavoparmelia caperata (L.) Hale sottoposto a fumigazioni con O3 e mantenuto a diversi regimi di idratazione e di umidità relativa ambientale. L'obiettivo di questo studio è stato quello di verificare se la tolleranza di questo lichene allo stress ossidativo derivante dall'esposizione all'O3 dipende da una strategia O3-avoidant, imputabile alla sua inattività metabolica durante le ore della giornata in cui si verifica il picco dell'O3, oppure da una O3-tolerant, dovuta invece alla presenza di un cospicuo ed efficace corredo di difese antiossidanti. Il primo studio ha dimostrato che il fotobionte algale al di fuori della simbiosi è in grado di resistere a livelli elevati di stress foto-ossidativo anche per periodi molto lunghi. Tuttavia è stato confermato che la simbiosi adduce benefici importanti come l'aumento della capacità di estinzione dell'energia accumulata dalle clorofille attraverso meccanismi non fotochimici e un ridotto effetto ossidativo indotto dal disseccamento. Questi risultati ci hanno permesso di sfatare l'ormai consolidata idea che i fotobionti algali, in particolare quelli del genere Trebouxia, siano particolarmente delicati e incapaci di tollerare autonomamente (al di fuori della simbiosi) fattori di stress abiotici come quelli che intervengono durante il disseccamento. Dai risultati del secondo studio è emerso che il fotobionte T. gelatinosa per far fronte alle importanti alterazioni dovute alla perdita d'acqua, si affida soprattutto a meccanismi che intervengono durante la fase di reidratazione. I più importanti coinvolgono molecole di riparazione “chaperone”, e. g. “Heath Shock Proteins”, e proteine della famiglia “Desiccation Related Proteins”, la cui funzione è ancora sconosciuta, ma visto l'elevato numero, la loro diversità intraspecifica e la sensibilità ai cambi di contenuto idrico, sembrano giocare un ruolo molto importante. Paradossalmente invece non sono state osservate alterazioni nell'espressione di geni collegati alle difese antiossidanti, che è sempre rimasta a livelli costitutivi. Ciò è stato interpretato come una strategia che permette all'organismo di avere sempre a disposizione mRNA per la neo-sintesi di nuovi enzimi coinvolti nelle difese antiossidanti. Infine nell'ultimo studio è stata riconfermata l'elevata resistenza del lichene F. caperata allo stress ossidativo derivato dall'esposizione all'O3 in quanto alla concentrazione utilizzata, ovvero il massimo registrato nell'ambiente alle nostre latitudini, non è stato osservato alcun effetto sulla vitalità nonostante sia stata osservata una notevole produzione di ROS. L'effetto ossidativo dell'O3 infatti è stato controbilanciato dalle difese antiossidanti le quali si sono mostrate altamente sensibili all'esposizione ed efficaci anche a bassi contenuti idrici. Lo stress ossidativo derivante da fattori abiotici di origine naturali e antropica dunque sembra essere gestito efficacemente sia dai licheni che dai loro fotobionti isolati, grazie ad efficienti difese antiossidanti e all'intervento di meccanismi di riparazione del danno. XXVI Ciclo 1983

[spa] Las esponjas de mar son determinantes en el bentos debido a su diversidad, abundancia, a que son refugio para otros organismos y a su influencia en los ciclos biogeoquímicos. Además, cuentan con defensas químicas cuya actividad citotóxica tiene potencial farmacéutico. Estas funciones que hacen relevante a las esponjas derivan en parte de su simbiosis con una compleja microbiota dominada por bacterias y específica de la especie de esponja considerada. Pero, hasta ahora, la mayoría de estudios se basan en muestras recogidas en un punto concreto en el tiempo y el espacio, por lo que desconocemos el potencial dinamismo de la interacción. En esta tesis tomamos como modelo esponjas simpátricas del género Ircinia para distinguir el efecto relativo de las condiciones externas y de la especie de esponja sobre la estructura de su comunidad bacteriana a escalas espaciales y temporales. En concreto, evaluamos el efecto de las corrientes y heterogeneidad espacial del ambiente (escala de cientos de kilómetros) sobre las comunidades bacterianas en esponjas de Las Bahamas (Ircinia felix e I. strobilina) (capítulo 1), y confirmamos si el mismo patrón ocurre también en las especies mediterráneas (I. fasciculata, I. variabilis e I. oros) (capítulo 2). Dado que el Mediterráneo Occidental se caracteriza por una marcada estacionalidad en las condiciones del agua también investigamos las comunidades bacterianas de estas especies en distintas estaciones del año (capítulo 3). Finalmente, considerando las recientes mortalidades masivas de esponjas en esta zona, testamos en experimentos de acuario si cambios anormales del ambiente (incremento de temperatura o disminución de la densidad de partículas en el agua) influyen en las comunidades simbiontes (capítulo 4). Para caracterizar las comunidades bacterianas combinamos microscopía electrónica y herramientas moleculares (librerías de clones y huella molecular de secuencias del gen ARNr 16S). Nuestros resultados demuestran que procesos específicos de la esponja, y no factores biogeográficos, son los principales responsables de estructurar las comunidades bacterianas simbiontes. La especificidad de las comunidades bacterianas respecto a la especie de esponja se mantuvo a las escalas espaciotemporales analizadas. Los experimentos de estrés no causaron ningún cambio significativo en la comunidad bacteriana. Proponemos que esta asociación, íntima y estable, ha resultado en un sistema cooperativo en el que la actividad de la propia comunidad, junto con la homeostasis del animal, contribuyen a la persistencia de la interacción frente a distintas condiciones ambientales., [eng] Marine sponges are a key component of benthic ecosystems in oceans all around the world, from shallow to deep waters, due to their diversity, abundance and influence in the cycle of nutrients. Moreover, the chemical defenses of the sponge against competitors, predators and fouling make the sponge a rich source of novel antitumoral drugs. But the relevance of sponge partially relies on their association with a complex microbial community that expands the metabolism of the host (e.g., via photosynthesis or nitrogen fixation) and takes part of metabolite synthesis. The symbiotic community is dominated by bacteria. One sponge specimen can host hundreds of bacterial taxa that are closely related with other sponge-derived bacteria but rare or absent in the surrounding environment (i.e., seawater and sediments). The sponge-associated bacterial communities are species-specific, but most of the studies are based on samplings at a particular point in time and space; thus, we ignore the potential dynamism of this interaction. The main objective of this PhD thesis was to identify the specificity and persistence of sponge-bacteria symbiosis through spatial and temporal scales. In particular, we used sympatric sponges of the genus Ircinia as a model to distinguish the relative role of environmental-related and host-related factors on the structure of their bacterial communities. In particular, we aimed to assess the effect of currents and spatial heterogeneity of the environment on the bacterial communities associated with sponges from the Bahamas (Ircinia felis and I. strobilina) at a scale of hundreds of kilometers (chapter 1) and confirm if the same pattern is applied to Mediterranean species (I. fasciculata, I. variabilis and I. oros) (chapter 2). Considering the marked seasonality in seawater conditions (i.e., temperature, irradiance, nutrient levels) in the Western Mediterranean Sea, we also investigated the bacterial communities in these sponges through different seasons (chapter 3). Recently, sponges and other filter-feeding invertebrates in the Mediterranean Sea have overcome mass mortality events; thus, we tested in aquaria experiments the potential influence of abnormal environmental changes (drastic increase of temperature and food shortage) in the symbiotic bacterial communities in I. fasciculata and I. oros. Bacterial communities were characterized by transmission electron microscopy and molecular tools (i.e., clone libraries and DNA fingerprinting of 16S rRNA gene sequences). The results derived from this thesis show that host-specific rather than biogeographic factors play a major role in structuring and maintaining sponge-associated bacterial communities. The bacterial communities in Ircinia spp. were species-specific and this specificity were maintained through hundreds of kilometers (chapters 1 and 2) and despite seasonality in seawater conditions (chapter 3). Moreover, stress conditions in aquaria experiments did not significantly affect the symbiotic bacterial communities (chapter 4). These results suggest a tight and stable link between the sponges and their bacterial communities. We proposed that this symbiosis have resulted in a cooperative system where the activity of the bacterial community, together with the homeostasis of the animal host, contribute to the persistence of the interaction under different environmental conditions.

[cat] La disponibilitat de la majoria dels fongs micorízics comestibles depèn de la seva fructificació natural. La formació de bolets està relacionada amb les característiques de l'hàbitat i les condicions climàtiques, però aquestes dades no expliquen ni la dinàmica de la fructificació ni del miceli d’aquests fongs. L’establiment de plantacions a partir de plantes micorizades pot ser una alternativa per a l'obtenció de fongs comestibles ectomicorízics. El progrés de les noves tecnologies en la biologia molecular han permès el desenvolupament, implementació i ús de tècniques per a la traçabilitat dels fongs ectomicorízics comestibles. A la tesi s'ha demostrat que la PCR en temps real, amb el disseny d'oligonucleòtids específics per a la detecció i quantificació de miceli extraradical, ens permet determinar la concentració de miceli present al sòl tant a boscos com a plantacions. La micorizació de plantes amb espècies del complex Boletus edulis s'ha aconseguit en condicions de cultiu pur. S’han dissenyat encebadors i sondes específics per l’amplificació de B. edulis i Tuber melanosporum per PCR en temps real. S’ha estudiat la dinàmica estacional del miceli extraradical, les ectomicorizes i la producció de B. edulis i Lactarius deliciosus, a dos boscos de Sòria. També s’ha quantificat el miceli extraradical de Rhizopogon roseolus (a dues plantacions) i de T. melanosporum (a una plantació), des del seu establiment. Per altra banda s’ha quantificat el miceli extraradical de T. melanosporum en una tofonera natural i en set plantacions (d’uns 20 anys). Finalment, s’ha analitzat l'estructura genètica d’una població de T. melanosporum a una plantació productiva, determinat la distribució dels tipus de compatibilitat al sòl, i els genotips de micorizes i ascocarps fent us de marcadors microsatèl•lits. No s'ha trobat relació directa entre les quantitats de miceli del sòl i la producció per cap de les espècies estudiades, però s’ha correlacionat positivament les estructures vegetatives de B. edulis, R. roseolus i T. melanosporum. Els resultats obren la possibilitat d'utilitzar la quantificació de miceli del sòl per PCR en temps real com un bon indicador de la colonització de les arrels en condicions de camp. Les quantitats de miceli extraradical de B. edulis, L. deliciosus i R. roseolus i les micorizes de T. melanosporum s’han correlacionat amb diferents paràmetres climàtics. Finalment, ha estat possible determinar la distribució dels diferents genotips de T. melanosporum a una plantació, on es va trobar una estructura genètica espacial amb un patró de distribució no aleatori, resultant en zones de camp colonitzat per genets que compartien els mateixos tipus de compatibilitat., [eng] The availability of most edible ectomycorrhizal mushrooms depends on their natural fructification. Therefore, mycorrhizal plant production could be an alternative for obtaining ectomycorrhizal edible fungi. The first step to establish a plantation for a certain species of mushrooms is the production of plants, inoculated with the fungus, in order to be outplanted to field. The mycorrhization of plants with species of the Boletus edulis complex has been achieved under pure culture synthesis conditions. The production of B. edulis mycorrhizal plants under nursery conditions could be achieved by acclimation of in vitro-produced mycorrhizal plants, but needs still more research to determine an appropriate procedure. Sporocarp formation of these fungi is linked to habitat characteristics and climate conditions, but these data alone do not explain all the trends of fungal fruiting and dynamics. It could be hypothesized that the amount of soil mycelia could also be related to the production of carpophores. Progress of new technologies in molecular biology and the availability of fungal genomes have led to the development, implementation and use of techniques for the traceability of edible ectomycorrhizal fungi. Through the thesis it has been demonstrated that the real- time PCR technique, with the design of specific oligonucleotides for the detection and quantification of extraradical mycelium in soil, allows us to determine the concentration of soil mycelium in forests and plantations, increasing detection limits over conventional PCR. Specific primers and probes have been designed for B. edulis and Tuber melanosporum for real-time PCR amplification, allowing the traceability of these fungal species in the controlled production of edible mycorrhizal mushrooms. The annual belowground dynamics of extraradical soil mycelium, ectomycorrhizal root tips and sporocarp production of two ectomycorrhizal fungi, B. edulis and Lactarius deliciosus, have been studied in two different pine forests (Pinar Grande and Pinares Llanos, respectively) in Soria in permanent plots. Quantification of extraradical mycelium of Rhizopogon roseolus x Pinus pinea plantations (two in Cabils) and of T. melanosporum x Quercus ilex plantation (one in Cerc), in Catalunya has been carried out from its establishment until 24 or 48 months. T. melanosporum extraradical mycelium has also been quantified by real-time PCR in a natural truffle ground and in seven truffle orchards (around 20 years old) established in Tierra Estella and Valdorba sites (Navarra). Finally, the spatial genetic structure of T. melanosporum population was analyzed in a productive orchard (France). The distribution of the two T. melanosporum mating types was monitored in the soil. Ectomycorrhizas and ascocarps were mapped and genotyped using simple sequence repeat markers and the mating type locus and their genetic profiles were compared. No direct relationships were found between soil mycelium amounts and sporocarp production for any of the studied fungal species, but it was possible to obtain positive correlations between vegetative structures (ectomycorrhiza and extraradical mycelium) for B. edulis, R. roseolus and T. melanosporum. The results obtained open the possibility of using quantification of soil mycelium by real-time PCR as a good indicator for root colonization in field conditions (in natural areas or in manmade orchards), especially when a nondestructive sampling or less time consuming analysis were required. The extraradical mycelial amounts of B. edulis, L. deliciosus and R. roseolus and T. melanosporum mycorrhizas were correlated with climate parameters as temperature, rainfall, solar radiation, relative humidity and evapotranspiration. Moreover, it has been possible to map the distribution of different T. melanosporum genotypes trough the traceability of ascocarps, ectomycorrhizas and soil samples. A pronounced spatial genetic structure was found. A nonrandom distribution pattern of the T. melanosporum was observed, resulting in field patches colonized by genets that shared the same mating types.

L’objectiu principal del projecte era aprofundir en el coneixement de les malalties de les esponges, centrant-nos en la diversitat bacteriana que acullen. Als estius 2008 i 2009 va haver episodis d’elevades temperatures de l’aigua de mar que van suposar importants mortalitats massives d’esponges a la Mediterrània. Contra tot pronòstic, els estius del projecte, el 2010 i el 2011, no van resultar especialment calorosos i no hi va haver episodis de mortalitat. És un fet molt positiu per les comunitats bentòniques però algun dels objectius específics de la meva proposta no es va poder dur a terme com havien estat platejats inicialment. Disposàvem de diferents mostres d’esponges malaltes de l’espècie Ircinia fasciculata, sanes i aigua circumdant recollides l’estiu 2009 i fixades per DNA, per això s’han pogut identificar i caracteritzar els canvis en la comunitat microbiològica de les esponges malaltes respecte de les sanes. Hem constatat que més que una infecció per un o pocs patògens puntuals, com havien proposat alguns autors, hi ha un canvi dràstic en la comunitat microbiològica associada a les esponges. Les esponges malaltes, on dominen els bacteris heterotròfics, presenten una major diversitat bacteriana que les sanes, on dominen els autòtrofs. Tot i que no es va poder realitzar un nou mostreig d’individus malalts, i algun objectiu específic no es va poder desenvolupar, vaig aprofitar l’estada en un centre de referència en estudis de la diversitat microbiana, per ampliar el coneixement general de les comunitats bacterianes associades a esponges. Es van realitzar nous estudis en què vam testar si totes les esponges (bacteriosponges i no) presenten simbionts reals o si les no-bacteriosponges presenten un enriquiment de les comunitats de l’aigua de mar però no una flora específica. El resultat és que totes les esponges presenten associacions molt específiques malgrat hi ha fortes diferències entre les comunitats microbianes associades a bacteriosponges i a no-bacteriosponges. The project aimed to deep in the knowledge of sponge diseases, focusing on their associated bacterial diversity. On 2008 and 2009 summers, there were important warm episodes of high seawater temperatures that caused mass mortalities of Mediterranean sponges. Unexpectedly, on summers 2010 and 2011 were not extremely hot and no mass mortalities occurred. This was a positive fact for benthic communities but some of the specific objectives from my proposal could not be performed as initially planned. We had samples from diseased and healthy sponges from Ircinia fasciculata and from their surrounding seawater from summer 2009, thus we have been able to identify and characterize changes in the diseased sponge microbiomes with respect to the healthy ones. We stated that disease is not caused by a single pathogen infection, as suggested by some authors. On the contrary, there is a shift in the microbial communities associated to sponges. Diseased sponges, in which heterotrophic bacteria are the most abundant microbes, present a higher bacterial diversity than healthy sponges, in which autotrophic bacteria dominate. Unfortunately we could not perform a new sampling on diseased sponges, and thus some specific objectives could not be addressed properly but I took advantage of my stay in a centre, which is reference for microbial diversity studies, to enlarge the basic knowledge on bacterial communities associated to sponges. We tested whether all sponges (bacteriosponges and not) present real symbionts or if non-bacteriosponges present and enrichment of seawater bacteria and not a specific microbiota. We found that all the sponges present species-specific bacteria although there are strong differences between the communities of bacterio and non-bacteriosponges.

[spa] El filo Porifera (Grant, 1836) está compuesto por metazoos sésiles con un sistema acuífero diferenciado del que forman parte los coanocitos que generan un flujo de agua unidireccional. A pesar de no presentar auténticos tejidos, las esponjas pueden llegar a desarrollar dos regiones bien definidas, el ectosoma (capa externa) y el coanosoma (región interna). Estos organismos representan un grupo ecológicamente importante del bentos marino con gran capacidad de adaptación y dispersión en muchos hábitats, contribuyendo así en la organización y funcionamiento a nivel de comunidad y ecosistema. Una de las claves del éxito evolutivo de las esponjas yace en la relación estrecha que presentan desde el Precámbrico con microorganismos a través de la cual desarrollaron una protección química. Muchas esponjas habrían utilizado los metabolitos secundarios de origen microbiano como defensa química. A día de hoy se han desarrollado dos áreas de investigación, la ecología química y la microbiana de esponjas, de las que realmente desconocemos su origen o su impacto. Dado el vacío existente de estudios que evalúen la comunidad bacteriana de esponjas como fuente de compuestos bioactivos, teníamos la oportunidad de integrar estos dos campos de la ecología de esponjas investigando la relación entre productos naturales y microorganismos simbiontes, con el fin de entender la funcionalidad de la comunidad bacteriana en el huésped. Esta tesis fue concebida para estudiar la ecología química y microbiana de la esponja Aplysina aerophoba (Nardo, 1833), cuya química y comunidad bacteriana asociada han sido objeto de muchos estudios previos. El principal objetivo fue explorar las fuentes de variación tanto de los productos naturales adscritos a Aplysina como de su estructura microbiana e inferir una posible relación entre comunidad de microorganismos y la producción de metabolitos secundarios. La aproximación que utilizamos consistía en explorar la variabilidad natural de los compuestos bioactivos y de la estructura microbiana de la esponja Aplysina aerophoba a distintas escalas espaciales (desde pocos centímetros hasta miles de kilómetros) y temporales (meses, años), y evaluar el efecto de factores ambientales, como la luz, en los perfiles químicos y microbianos. Posteriormente, correlacionar ambos patrones de variación e inferir alguna asociación potencial entre productos naturales y simbiontes microbianos. Resumiendo, la producción de metabolitos secundarios en esponjas y la composición filogenética de la microbiota asociada depende esencialmente de la especie de esponja, de los factores ecológicos con variación espacial y temporal, como también del estado del huésped (si presenta o no estrés). La combinación entre factores abióticos y bióticos determinará en última instancia la abundancia de defensas químicas y la diversidad microbiana debido a una autorregulación entre ambos tipos de factores, [eng] Phylum Porifera (Grant, 1836) are sessile metazoans with a differentiated inhalant and exhalant aquiferous system with external pores. Lacking a tissue grade of construction, sponges can reach two well-differentiated regions, the ectosome (external layer free of choanocytes) and the choanosome (internal region with choanocytes). As the most likely primitive metazoans, their challenging structural organization, physiology for biocalcification and trophic requirements allowed sponges to rapidly colonize distinct environments and built important sponge reefs during the Paleozoic and Mesozoic eras, making them an ecologically relevant group principally in marine benthic communities. To date, sponges are still ecologically important among benthic fauna although the role as reef builders in modern coral reefs has changed in favor of scleractinian corals. Nonetheless, sponges have demonstrated a huge capacity to adapt and spread in many habitats contributing to organization and functioning at both community and ecosystem levels. One of the keys of the evolutionary success of this group lies in the close association between sponges and microbes that dates back to the Precambrian era. The need to be defended may have arisen from the lack of motility of sponges and several mechanisms emerged to fulfill their demand including a chemical protection. Many sponges would have taken advantage of associated microbes to use their metabolites as a defense barrier against predators, competitors or foulers. This particular symbiosis has consequently become a key factor in biotic interactions within the sponge research. To date, chemical ecology and microbial ecology are two independent areas of the sponge research with ecological implications that occasionally converge at the same point. We want to analyze the evolution of the sponge chemical and microbial ecology from the very beginning, to quantify their impact on the scientific community, and to compare both research areas. This PhD dissertation has been conceived to study the chemical and microbial ecology of sponges using the demosponge Aplysina aerophoba (Nardo, 1833) as a model species because its secondary chemistry and its associated microbial community are well studied and it is quite abundant in our study area (Northwestern Mediterranean and Canary Islands). Beyond the knowledge achieved about the major chemistry and bacterial assemblages in A. aerophoba, we have been able to explore the variation sources of the natural products and the sponge microbial consortium. Additionally, we have assessed the putative relationships between the host bacterial community and the production of secondary metabolites in this species. We explored changes in the abundance of secondary metabolites and the relative composition of bacterial assemblages in A. aerophoba at multiple spatial (from few centimeters to thousand kilometers) and temporal (months and years) scales. The approach used allowed us to investigate which is the magnitude of the variance attributable to the distinct spatial and temporal scales and the most relevant scale at which the abundance of secondary metabolites and bacterial symbionts varied. We also investigated the relationship between natural products and microbial community structure by assessing whether both parameters covary at multiple scales. Finally, we experimentally addressed whether different light exposures can modify chemical and microbial profiles in the external and internal regions of A. aerophoba. In summary, the production of natural products in sponges and the abundance and phylogenetic composition of the host-associated microbial community mainly depend to a large extent on the sponge-species and the ecological factors with spatial and temporal variations (e.g., light, predation, competition, fouling). The host state (i.e., stress) is also a key factor that may be the main driver of symbiotic shifts causing a breakdown in the sponge health and making the symbiont communities unstable and likely the sponge chemical defense. The combination between abiotic and biotic factors may finally determine the concentration of bioactive compounds and associated microbial diversity as the abiotic environmental context can control the outcomes of biotic interactions, and biotic interactions often moderate the effect of abiotic factors. For that reason, it is not an easy task to actually figure out the factors that limit or enhance chemical and microbial variability. Further experiments and time-series observations are needed to reveal the underlying processes hidden.

Bactrocera oleae, fitofago chiave dell’agroecosistema olivo, è presente in Italia in tutti gli areali interessati dalla coltura, tranne in alcune aree caratterizzate da maggiore altitudine dove il fattore termico non consente lo sviluppo della specie. Il dittero è fortemente legato alle temperature che del resto condizionano anche la fenologia dell’olivo; in effetti il numero di generazioni che la mosca può completare nell’anno varia da 1 fino a 4-5 in zone con temperature medie annue elevate (zone costiere e/o meridionali). La pericolosità della specie è pertanto legata al numero di generazioni e all’andamento climatico che, a seconda dell’annata e della zona, possono variare sensibilmente condizionando la densità di popolazione e quindi il grado di dannosità potenziale del fitofago. Recenti ricerche sul comportamento e sulla biologia del tefritide hanno messo in evidenza come il fitofago, nel tempo, abbia contratto con i batteri una simbiosi mutualistica che permette al dittero di aumentare il proprio potenziale biotico. Nel presente articolo, dopo un breve excursus sulla biologia e sui danni causati dal fitofago, viene fatto il quadro delle attuali strategie di lotta ammesse nei protocolli dell’olivicoltura integrata e biologica. The control of the olive fruit fly in integrated and organic olive crops. Bactrocera oleae (Rossi) is the key pest of the olive agroecosystem; it is distributed in all Italian olive crops, except in some areas at higher altitude where low temperatures do not allow the development of the fly. The olive fruit fly development is strictly affected by temperature. It can complete from one up to five generations per year in areas with high annual average temperature (coastal and/ or southern areas). The harmfulness of the species is related to the number of generations and weather conditions which may fluctuate considerably year by year, region by region. Recent researches on behavior and natural history of the tephritid fly have pointed out that it has developed a mutualistic symbiosis with bacteria which allows an increase of its growth rate. In this article authors present control strategies permitted in integrated and organic olive crops. The currently widespread early harvesting and timely milling reduce the harmful influence of late olive fruit fly infestations; together with mass trapping and with repellent/ oviposition deterrent sprays by copper products and clays, these practices allow an increasingly sustainable effective control of the olive fruit fly

Gli Imenotteri sono organismi aplo-diploidi che si riproducono per partenogenesi arrenotoca. Molte specie però si caratterizzano per l'assenza della riproduzione sessuale e per l'esclusiva produzione di progenie femminile diploide da uova non fecondate. Questa forma di riproduzione, nota come partenogenesi telitoca, può essere geneticamente determinata o indotta da batteri simbionti intracellulari dei generi Wolbachia, Rickettsia e Cardinium. Questi causano il ripristino della diploidia nelle uova non fecondate che quindi originano progenie femminile. Leptocybe invasa Fisher & La Salle è un fitofago di origine australiana di recente introduzione in Italia. Esso attacca varie specie di eucalipto causando la formazione di galle globose singole e multiloculari su nervatura principale e picciolo delle foglie, su rametti e germogli, che possono essere fortemente compromessi. In questo lavoro è stata studiata una popolazione telitoca di L. invasa presente in Portici (NA): il 100% degli individui raccolti in campo in varie epoche dell'anno è risultato di sesso femminile, confermando quanto generalmente osservato per questa specie nell'areale di origine ed in altre zone di diffusione. Femmine adulte sono state sottoposte ad indagini molecolari o di microscopia a fluorescenza per evidenziare la presenza di batteri simbionti. Mediante screening con PCR per la ricerca di batteri simbionti responsabili di alterazioni della riproduzione negli artropodi è stato evidenziato che il 100% delle femmine adulte risultava infetto da Rickettsia. Lo strain del simbionte è stato caratterizzato mediante sequenziamento e analisi filogenetica dei geni 16S rRNA, gltA e atpA. L'ibridazione in situ (FISH) con sonde oligonucleotidiche fluorescenti per il 16S rRNA ha mostrato un'alta densità di Rickettsia negli ovarioli, negli oociti e nelle uova completamente sviluppate. I risultati ottenuti dimostrano che i batteri simbionti sono trasmessi verticalmente (transovaricamente) dalla madre alla progenie con elevata efficienza (100% di femmine infette) lasciando intravedere un ruolo fondamentale della Rickettsia nella riproduzione di L. invasa. Rickettsia potrebbe indurre la partenogenesi telitoca, come osservato in altri Eulophidae. Un protocollo per il trattamento con antibiotici di femmine infette, allo scopo di ottenere da queste ultime la produzione di progenie maschile, è in via di definizione per attestare il ruolo di Rickettsia quale agente causale della telitochia in L. invasa. Non sono, infine, da escludere altri effetti del simbionte sulla fitness dell'ospite.

In questo studio cerchiamo di riflettere sullo stato della lingua inglese e spagnola in contatto negli Stati Uniti d’America, e sul fenomeno che nasce da questo incontro, ovvero ciò che popolarmente si definisce spanglish. Il mondo latino e l’anglosassone sono differenti per sensibilità, cultura e lingua. Vivono in modo diverso, reagiscono in modo differente a determinate situazioni. Tuttavia, la complessità della condizione plurale di questi latinos quando si manifesta negli Stati Uniti d’America potrebbe dare vita a esperienze affascinanti, frutto di queste due realtà, di questo vivere in-between. Crediamo che in un mondo sempre più globalizzato sia di grande interesse osservare l’uso di strategie verbali che mettano in comunicazione i parlanti, ovvero i numerosi latinos che vivono oggi nel territorio statunitense, dove lo spanglish è diventato per molti un efficace mezzo di comunicazione in ambiti informali, che permette di esprimere una identità in-between e, al tempo stesso, una identità linguistica.