Conselho Nacional de Desenvolvimento Científico e Tecnológico / Bees of the genus Apis are widely distributed throughout the tropical regions of the planet, playing fundamental role as pollinators. In Brazil they are a polihibrid formed by the crossbreed of African subspecies Apis mellifera scutellata and European subspecies, where due generalist habits the introgression of alleles of the African subspecies has led to a predominance of the your characteristics in relation to European subspecies. The scope of this work was to characterize the divergence among 71 colonies of Africanized honey bees located in three distinct ecoregions (Forest zone, Ecotone and Semiarid) of the State of Sergipe Brazilian northeast, through morphological and behavioral analyses, in order to assess the relationship between the effects of seasonality and the different patterns morphoclimatic ecoregions in morphology, behavior and distribution of these groups of bees. In this work we used geometric morphometric techniques observing the anatomical landmarks of the wing venation with the aid of software Tps / DIG and evaluation of hygienic behavior by pin-killing method in two distinct seasonal periods, the dry and rainy. The correlation between the hygienic behavior indexes and environmental variables was obtained by Spearman correlation and the causal relations by path analysis, with the aid of software R. The morphometric analyzes were performed by means of multivariate analysis with the aid of software MORPHOJ and PAST. Thus, the results of this study demonstrated that the high gene flow evidenced between studied colonies and pronounced differences in apiaries and ecoregions with influence of altitude on shape (r=0,06239; p= 0.05) and size (0.001) contributed therefore for the separation of these groups as result of phenotypic plasticity rather than genetic divergence among populations of Africanized honey bees. Furthermore, the results also demonstrated significant difference in hygienic behavior of these populations between the dry and rainy season (p= 0,022; α=0,05) and between ecoregions (p=0,001; α=0,05) with the influence of temperature (ρ=0,065; p=0,471; α=0,05) and altitude (ρ=-0,294; p=0,001 α=0,05) upon pluviosity (ρ=0,274; p=0,002; α=0,05) that demonstrated be the main modulator of hygienic behavior, thus reinforcing the influence of environmental factors on the expression of this trait. Therefore, it is concluded by the influence of stochastic factors in the morphology, behavior and distribution of Africanized honey bees, where polyphenisms found denote the high genetic variability of these populations, a fact that can be exploited in future conservation, handling and breeding programs. / As abelhas do genero Apis estao amplamente distribuidas pelas regioes tropicais do planeta, sendo fundamentais no papel de polinizadores. No Brasil, estas sao um poliibrido formado pelo cruzamento entre a subespecie africana Apis mellifera scutellata e as subespecies europeias. Devido a habitos generalistas, a introgressao de alelos da subespecie africana tem levado a uma predominancia nas caracteristicas desta em relacao as europeias. O presente trabalho teve como escopo a caracterizacao da divergencia entre 71 colonias de A. mellifera africanizadas, situadas em tres distintas ecorregioes (Zona da Mata, Agreste e Sertao) do Estado de Sergipe, nordeste do Brasil, por meio de analises morfologicas e comportamentais, com o objetivo de avaliar as relacoes entre os efeitos da sazonalidade e dos distintos padroes morfoclimaticos das ecorregioes na morfologia, comportamento e distribuicao desses grupos de abelhas. Neste estudo foram utilizadas tecnicas de morfometria geometrica, com observacao dos marcos anatomicos da venacao alar, com o auxilio do software Tps/DIG e avaliacao do comportamento higienico pelo metodo de perfuracao de crias em dois periodos estacionais, o seco e o chuvoso. A correlacao entre os indices de comportamento higienico e as variaveis ambientais foi obtida por meio da correlacao de Spearman e as relacoes de causalidade por meio da analise de trilha, com o auxilio do software R. As analises morfometricas foram realizadas por meio de tecnicas de analise multivariada, com o auxilio dos softwares MORPHOJ e PAST. Assim, os resultados deste trabalho demonstraram que o intenso fluxo genico evidenciado entre as colonias estudadas e as diferencas pronunciadas nos distintos apiarios e ecorregioes, com influencia da altitude na forma (r=0,06239; p= 0.05) e tamanho (0.001) contribuiram, portanto, para a separacao desses grupos como resultado da plasticidade fenotipica e nao de divergencia genetica entre as populacoes de abelhas africanizadas. Alem disso, os resultados tambem demonstraram haver diferenca significativa no comportamento higienico dessas populacoes, entre os periodos seco e chuvoso (p= 0,022 ¿=0,05) e entre as ecorregioes (p=0,001; ¿=0,05), com influencia da temperatura ( Ï=0,065 p=0,471; ¿=0,05) e altitude ( Ï=-0,294; p=0,001; ¿=0,05) sobre a pluviosidade ( Ï=0,274 p=0,002; ¿=0,05) sendo esta o principal modulador do comportamento higienico, reforcando a influencia de fatores ambientais na manifestacao dessa caracteristica. Portanto, conclui-se pela influencia de fatores estocasticos na morfologia, comportamento e distribuicao das abelhas africanizadas, onde os polifenismos encontrados denotam a grande variabilidade genetica dessas populacoes, fato esse que pode ser explorado em futuros programas de conservacao, manejo e melhoramento.

Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2017-05-22T15:55:42Z No. of bitstreams: 2 Tese - Leandro Maracahipes dos Santos - 2017.pdf: 3094765 bytes, checksum: a7fa8f585e1539956b511e26bdb50212 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2017-05-22T15:56:58Z (GMT) No. of bitstreams: 2 Tese - Leandro Maracahipes dos Santos - 2017.pdf: 3094765 bytes, checksum: a7fa8f585e1539956b511e26bdb50212 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2017-05-22T15:56:58Z (GMT). No. of bitstreams: 2 Tese - Leandro Maracahipes dos Santos - 2017.pdf: 3094765 bytes, checksum: a7fa8f585e1539956b511e26bdb50212 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017-04-13 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The adoption of different ecological strategies is an important factor to determine the establishment and persistence of species in local communities. In general, the Cerrado is characterized by high fire frequency and poor soils. Generally under conditions of low fertility and high fire frequency the filtered species tend to have characteristics that represent adaptations to these environmental stresses. Considering that savanna species evolved under severe environmental filters, our aim was to evaluate how the adoption of different ecological strategies can determine the performance of the functional traits, the structure of the communities, and the relationship between a focal plant and its neighborhood. In this thesis work, which is divided into three chapters, we use three different scales to evaluate how species ecological strategies can determine the performance and establishment in local communities. In the first chapter, which is based on habitat scale, we evaluated how ecological strategies of generalist and specialist species of seasonal forest and savannas are fundamental for the establishment and persistence of the species in these habitats with marked differences in frequency in fire frequency and nutrient availability. In this chapter, we discuss that the different strategies adopted by species are in accordance to the limiting factors of the species occurrence in each of these environments. In the second chapter, which is based on community scale, we seek to understand how environmental gradients can determine different ecological strategies related to functional traits and density of individuals. We showed that the changes in trait values and density of individuals were more evident in the fertility gradient than toxicity, and that seasonal forest communities were more sensitive to changes savanna communities in both gradients. We also observed that species with conservative traits were associated with poor soils and species with acquisitive traits with more fertile soils. In the third chapter, which was developed at the individual scale, we discussed whether the characteristics and phylogenetic relationship of the neighboring plants influence leaf damage in trees and shrubs of savannas. In this chapter, we showed that the ecological and evolutionary distance between individual plants and neighboring plants does not determine the level of leaf damage by herbivores. We discussed that the dominance of generalist herbivores, co-evolution between plants and specialist herbivores, and preferential consumption of young leaves may be more important to determine the level of leaf damage than the neighboring context in which a given plant is inserted. / A adoção de diferentes estratégias ecológicas é um fator importante para determinar o estabelecimento e a persistência de espécies em comunidades locais. De maneira geral, o cerrado é caracterizado por uma alta frequência de fogo e solos pobres em nutrientes. Geralmente em condições de baixa fertilidade e alta frequência de fogo as espécies filtradas tendem a possuir características que representam adaptações a estes estresses ambientais. Considerando que as espécies de Cerrado se desenvolvem sob a atuação destes filtros ambientais, nosso objetivo foi avaliar como a adoção de diferentes estratégias ecológicas podem determinar a performance dos atributos funcionais, a estrutura das comunidades e a relação entre uma planta focal e sua vizinhança. Neste trabalho de tese, que está dividido em três capítulos, nós utilizamos três diferentes escalas para avaliar como estratégias ecológicas das espécies podem determinar seu desempenho e estabelecimento em comunidades locais. No primeiro capítulo que está baseado em uma escala de habitat, nós avaliamos como as estratégias ecológicas de espécies generalistas e especialistas de floresta estacional e cerrado sentido restrito são fundamentais para o estabelecimento e a persistência das espécies nestes habitats com diferenças marcantes em relação à frequência de fogo e disponibilidade de nutrientes. Neste capítulo, nós discutimos que as diferentes estratégias adotadas pelas espécies estão de acordo com os fatores limitantes da ocorrência de espécies em cada um destes ambientes. No segundo capítulo, que está baseado em escala de comunidades, nós buscamos compreender como os gradientes ambientais podem determinar diferentes estratégias ecológicas relacionadas aos atributos funcionais e a densidade de espécies. Nós demonstramos que as mudanças nos valores de atributos e densidade de espécies foram mais claras no gradiente de fertilidade do que toxicidade, e que comunidades de floresta estacional foram mais sensíveis a mudanças do que comunidades de cerrado sentido restrito em ambos os gradientes. Nós observamos também que espécies com atributos conservativos foram associados à solos pobres e espécies com atributos aquisitivos associado à solos mais férteis. Já no terceiro capítulo, que foi desenvolvido na escala de indivíduo, nós discutimos se as características e relação filogenética das plantas vizinhas influenciam o dano foliar em árvores e arbustos do cerrado. Neste capítulo, demonstramos que a distância ecológica e evolutiva entre plantas individuais e as plantas vizinhas não determina o nível de consumo foliar por herbívoros. Nós discutimos que a dominância de herbívoros generalistas, a co-evolução entre plantas e herbívoros especialistas, e o consumo preferencial de folhas jovens podem ser mais importante para determinar o nível de dano foliar do que o contexto de vizinhança em que uma dada planta está inserida.

Este trabalho objetivou a avaliação da presença de plasticidade fenotípica e de adaptação local de três procedências de palmiteiro: Ombrófila Densa, Estacional Semidecidual e Restinga, em três locais no Estado de São Paulo: Parque Estadual da Ilha do Cardoso, Parque Estadual de Carlos Botelho e Estação Ecológica dos Caetetus, em ensaios de adaptação no estabelecimento (ou de semeadura) e de adaptação em juvenis (ou de crescimento). Os conjuntos de dados foram analisados utilizando estruturas de grupos de experimentos, com efeitos cruzados e aninhados. As variáveis relacionadas com a massa de matéria seca das plantas, nos dois ensaios, foram analisadas usando a abordagem de modelos lineares de efeitos mistos, por meio da incorporação de fatores de efeito aleatório, e fazendo uso do método da máxima verossimilhança restrita (REML) para estimação dos componentes de variância associados a tais fatores com um menor viés. Por outro lado, para a proporção de sementes germinadas, no ensaio de adaptação no estabelecimento, a análise estatística foi realizada a partir da abordagem dos modelos lineares generalizados mistos, sob a pressuposição de que a variável segue uma distribuição binomial, com função de ligação logito. O método da pseudo-verossimilhança foi empregado para obtenção da solução das equações de verossimilhança. Os resultados mostraram que as plantas originadas de sementes dos três biomas avaliados apresentaram um comportamento plástico, para todos os caracteres avaliados no ensaio de adaptação no estabelecimento. Com relação ao ensaio de adaptação em juvenis, a característica de plasticidade foi verificada somente para a massa de matéria seca da folha em plantas provenientes do bioma Estacional Semidecidual. A característica de adaptação local, apresentou-se de forma evidente no ensaio de adaptação no estabelecimento. Estes resultados evidenciaram que em cada local avaliado, as plantas originadas das sementes de diferentes procedências apresentaram um comportamento diferenciado nos caracteres relacionados à massa de matéria seca, podendo em alguns casos, tratar-se de adaptação local. Concluiu-se que os locais Carlos Botelho e Ilha do Cardoso são os mais favoráveis para a germinação das sementes de sua mesma procedência. / The aim of this work was to evaluate the presence of phenotypic plasticity and local adaptation of three provenances of the palm specie Euterpe edulis: Atlantic Rainforest, Seasonally Dry Forest and Restinga Forest, in permanent parcels inserted in three forest types of the São Paulo State (Brazil): Parque Estadual da Ilha do Cardoso, Parque Estadual de Carlos Botelho e Estação Ecológica dos Caetetus, in experiments of seedling establishment and juveniles plants growth. The data sets were analyzed using structures of groups of experiments, with crossed and nested effects. The variables related to dry matter content of plants in both assays were analyzed using linear mixed models (LMM) approach, through the incorporation of random effect factors, and using the restricted maximum likelihood method (REML) for estimation of variance components associated with these factors with a minor bias. On the other hand, germination proportion of the seeds at seedling establishment assay was analyzed using the generalized linear mixed models (GLMM) approach, under the assumption that the variable follows a binomial distribution, with logit link function. The pseudo-likelihood (PL) method was used to obtain the numerical solution of the likelihood equations. The results showed that, plants from seeds of the three biomes evaluated presented a plastic behavior for all characters assessed in the seedling establishment assay. In respect to juveniles adaptation assay, the phenotypic plasticity characteristic was observed only to the leaf dry matter content of plants from Seasonally Dry Forest biome. The local adaptation characteristic was clearly observed in the seedling establishment assay. These results showed that at each site evaluated, plants originating from seeds of different provenances exhibited different behavior on characters related to the dry matter content and may in some cases be local adaptation. It was concluded that locations Carlos Botelho and Ilha do Cardoso are the most favorable for seed germination of its same provenance.

Submitted by isabela.moljf@hotmail.com (isabela.moljf@hotmail.com) on 2017-04-26T15:25:01Z No. of bitstreams: 1 alineamaliadovale.pdf: 14261579 bytes, checksum: 2f07c357436da6480d7aa53e8394fa36 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2017-05-12T15:47:28Z (GMT) No. of bitstreams: 1 alineamaliadovale.pdf: 14261579 bytes, checksum: 2f07c357436da6480d7aa53e8394fa36 (MD5) / Made available in DSpace on 2017-05-12T15:47:28Z (GMT). No. of bitstreams: 1 alineamaliadovale.pdf: 14261579 bytes, checksum: 2f07c357436da6480d7aa53e8394fa36 (MD5) Previous issue date: 2010-02-26 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / FAPEMIG - Fundação de Amparo à Pesquisa do Estado de Minas Gerais / Lippia alba (Verbenaceae), popularmente conhecida no Brasil como erva cidreira, é amplamente distribuída nas Américas, onde ocorre em praticamente todos os tipos de ambientes, sendo muito cultivada para uso medicinal. A espécie apresenta grande plasticidade fenotípica, sendo possível observar variações quanto ao hábito, filotaxia, forma e dimensão das folhas, o que dificulta sua classificação taxonômica e a sua utilização na farmacologia. Análises anteriores revelaram a existência de diferentes quimiotipos com diferentes atividades farmacológicas. A proposta deste trabalho foi entender a ampla variação fenotípica existente em L. alba, por meio de uma abordagem multidisciplinar, utilizando 32 acessos da espécie coletados em diferentes regiões do Brasil e mantidos sob as mesmas condições ambientais. Além disso objetivou-se contribuir para a caracterização dos acessos e entender melhor os padrões de especiação em Lippia. Dentre os acessos analisados foram encontradas variações morfológicas tanto em caracteres vegetativos quanto em caracteres reprodutivos. Por meio da estimativa da quantidade de DNA por citometria de fluxo foi possível dividir os acessos em sete grupos com quantidades significativamente diferentes de DNA. Os grupos variaram de 2,31 pg a 6,70 pg de DNA. Na contagem cromossômica realizada por análises em células meióticas e mitóticas foram observados seis números cromossômicos diferentes, 2n=30, 2n=34, 2n=51, 2n=58, 2n=60 e 2n=93, evidenciando níveis de ploidia diferentes na espécie. Na análise palinológica foram observados grãos de pólen com abertura di, tri ou tetracolporadas. Os grupos com acessos diplóides e com menores quantidades de DNA apresentaram apenas grãos tricolporados. Os grãos di e tetracolporados foram observados em acessos com maiores níveis de ploidia. Apesar dos resultados do presente estudo não terem auxiliado na divisão de grupos morfológicos bem definidos, eles demonstram que mesmo sob condições controladas os acessos apresentaram variações morfológicas evidenciando a existência de variação genética como um fator importante para explicar a grande plasticidade fenotípica observada. A existência de níveis de ploidias diferentes sugere que a espécie Lippia alba pode estar em processo de especiação. Além das variações morfológicas e citogenéticas, as variações estomáticas e palinológicas reforçam essa conclusão. / Lippia alba (Verbenaceae), commonly known as erva cidreira in Brazil, is largely widespread in the Americas, where it grows in almost all environments. It is frequently grown for medicinal use. The species presents a high phenotypic plasticity, varying in habit, phyllotaxy, leaf form and size, thus putting difficulties to its taxonomical classification and use in pharmacology. Past analyses revealed the existence of different chemotypes with different pharmacological activities. The proposal of this work was understanding the great phenotypic variation observed in L. alba by making use of a multidisciplinary approach, using 32 accessions of the species collected in different Brazilian regions, and maintained in the same environmental conditions. Furthermore, another goal was characterizing the acessions and to better understand the speciation patterns ocurring in Lippia. Were found morphological variations, among the analyzed accessions, in vegetative and reproductive characters. As a result of estimating DNA quantity by means of flow cytometry, it was possible to split the accessions in seven groups with significant different quantities of DNA. Groups varied between 2.31pg and 6.70pg of DNA. In the chromosomal counting made by means of analyses in meiotic and mitotic cells, were observed six distinct chromosomal numbers (2n=30, 2n=34, 2n=51, 2n=58, 2n=60 e 2n=93), showing different ploidal levels in the species. In the pollen grains analysis were observed di, tri or tetracolporate pollen aperture. Groups with diploid accessions and smaller amounts of DNA showed only tricolporate grains. Even though the results of this study have not contributed in the division of well-defined morphological groups, they demonstrate that even under controlled conditions the accessions present morphological variations showing the existence of genetic variation as an important factor for explaining the great phenotypic plasticity observed. The existence of different ploidal levels suggests that L. alba can be in progress of speciation. Besides morphological and cytogenetic variations, those stomatal and palynological reinforces this conclusion.

Lors des interactions tri-trophiques impliquant une plante hôte, ses insectes phytophages et leurs ennemis naturels (parasitoïdes, prédateurs...), chaque niveau trophique est fortement dépendant des autres. La plante hôte peut influencer directement les traits d’histoire de vie des insectes phytophages et indirectement les ennemis naturels se développant aux dépens de ces insectes phytophages. Lorsque qu’un ennemi naturel comme un parasitoïde attaque l’insecte phytophage, son système immunitaire constitue sa dernière chance de survie. Une grande variation dans l’immunité des insectes est généralement observée dans les populations naturelles, suggérant que différentes pressions de sélection peuvent moduler et conduire à une adaptation des paramètres immunitaires. Ma thèse vise à déterminer les influences conjointes de la plante hôte et des parasitoïdes, sur les paramètres immunitaires des chenilles de deux ravageurs de la vigne, Cochylis (Eupoecilia ambiguella) et Eudémis (Lobesia botrana).Durant ces 3 années, nous avons mis en évidence une forte influence du cépage de vigne sur les effecteurs immunitaires des chenilles de vers de la grappe. De plus, le cépage de vigne semble être à l'origine d'un compromis entre les voies immunitaires constitutives et induites. La présence variable de bactéries à la surface des baies ne semble pas être à l'origine de ce compromis. Outre le cépage de vigne, nous avons démontré une forte action des parasitoïdes sur l'immunité des vers de la grappe. A l'échelle nationale, les populations d’Eudémis les plus immunocompétentes sont également les populations les plus parasitées. Cette corrélation positive entre le succès de parasitisme et les paramètres immunitaires des chenilles ne semble pas expliquée par une réponse plastique du système immunitaire des chenilles à la présence des parasitoïdes, mais plutôt par une sélection locale du système immunitaire, en réponse à la pression de parasitisme subie par ces chenilles sur plusieurs années. Les différentes études réalisées dans le cadre de ma thèse confirment la complexité des relations tri-trophiques entre la plante hôte, l’insecte phytophage et ses ennemis naturels. L’intégration du système immunitaire de l’insecte phytophage semble primordiale dans la compréhension des interactions unissant ces trois protagonistes. / In tritrophic interactions involving phytophagous insects, host plants and natural enemies, trophic levels are highly dependent on each other. Host plant may strongly affect directly phytophagous insect and indirectly natural enemies growing on these phytophagous insects. When a natural enemy attacks a phytophagous insect, the host immune system constitutes the last chance for the host to survive to an infection. A great variation of insect immune system is generally found in populations for susceptibility to pathogens, suggesting that variable selection pressures may have shaped and driven adaptation of immune traits. This project aims to determine the influence of both host plant and natural enemies on the larval immune system of grapevine moth pests, Lobesia botrana and Eupoecilia ambiguella.During these three years, we have demonstrated a strong influence of grape variety on immune effectors of grapevine moth larvae. In addition, the grape variety modulates a trade-off between the constitutive and induced immune pathways. The variable presence of microbes on the surface of grape berries does not explain the trade-off in immune function. Beyond the grape variety effect, we also demonstrated a strong influence of parasitoids on the immune parameters of the grapevine moth larvae. In France, the most immunocompetent populations of grapevine moth are also the most parasitized. This positive correlation between successful parasitism and larval immune parameters seems not explained by a plastic response of the larval immune system to parasitoids presence, but rather by a local selection of larval immune system in response to parasitism pressure suffered by larvae for several years.The different experiments realized in my thesis confirm the complexity of the tri-trophic interactions between host plant, phytophagous insects and natural enemies. The integration of phytophagous insect immune system seems essential in understanding the interactions linking these three protagonists.

Cette thèse visait à étudier la variabilité génétique et plasticité phénotypique de la vulnérabilité à la cavitation chez le hêtre (Fagus sylvatica L.). A cette fin, nous avons tout d’abord testé les variations dues à la méthodologie de mesure de la vulnérabilité à la cavitation. Notre étude a montré que les variations de vulnérabilité à la cavitation au cours du temps sont faibles. Néanmoins, il est préférable d’éviter de récolter les échantillons durant le début de la période de formation du bois. Par ailleurs il est possible de conserver au frais les échantillons sans dégrader les mesures durant au moins un mois. Nos résultats montrent également que la vulnérabilité à la cavitation peut être variable aussi bien au sein d’un même arbre qu’entre populations in situ. Ensuite, nous avons voulu déterminer la part de plasticité phénotypique de la part de variabilité génétique dans la variabilité de la vulnérabilité à la cavitation. Pour cela nous avons étudié 17 populations de hêtre venant de toute l’Europe et poussant dans une plantation comparative. Parmi les 17 populations 6 d’entre elles ont été étudiées dans trois plantations comparatives différentes (France, Espagne et Slovaquie). Nos résultats indiquent que chez le hêtre la vulnérabilité à la cavitation varie considérablement au sein de chaque population. Ils indiquent également que l’on observe peu de différenciation génétique entre populations. Les résultats montrent également que la plasticité phénotypique de la vulnérabilité à la cavitation est importante entre les plantations, et que le degré de cette plasticité peut varier d’une population à l’autre. Pour finir, nous avons regardé s’il existait des relations entre la vulnérabilité à la cavitation et des paramètres d’efficience hydraulique ainsi qu’avec l’efficience d’utilisation de l’eau. Nos résultats ne permettent pas de mettre en évidence des preuves d’un trade-off entre l’efficience et la sureté du xylème. / This work aimed at studying the genetic variability and the phenotypic plasticity of vulnerability to cavitation in beech (Fagus sylvatica L.). We tested the variations due to the methodology of measuring vulnerability to cavitation. Our study showed that the variations in vulnerability to cavitation over time are low. However, it’s better to avoid collecting samples during the period of initial wood formation. Furthermore it’s possible to store samples without degrading measures for during one month. Our results also show that vulnerability to cavitation can be variable both within the same tree and between populations in situ. We determined the proportion of phenotypic plasticity and the proportion of genetic variability in the variability of vulnerability to cavitation. For this we studied 17 beech populations from all Europe and growing in a common garden. Among the 17 populations 6 of them have been studied in three different common gardens (France, Spain and Slovakia). Our results indicate that for beech, vulnerability to cavitation varies considerably within populations. They also indicate that there are few genetic differentiations between populations. The results show that the phenotypic plasticity of vulnerability to cavitation is important among common garden, and the degree of this plasticity can vary between populations. To complete our study, we looked at the relationships between vulnerability to cavitation and hydraulic efficiency parameters and with the water use efficiency. Our results do not reveal evidence of relationships vulnerability to cavitation and other physiological traits.

La compréhension des mécanismes déterminant le succès des espèces invasives est une étape essentielle dans la gestion des invasions biologiques actuelles et la prédiction des futurs risques d’invasion. En adoptant un cadre d’étude conceptuel intégrant les processus écologiques et évolutifs, l’objectif de ce travail était d’analyser les déterminants de la colonisation de l’ambroisie à feuilles d’armoise en France. Tout d’abord, l’étude des interactions biotiques et abiotiques a permis de montrer la capacité de tolérance de l’ambroisie à l’herbivorie et au stress hydrique. L’ambroisie est capable de tolérer la défoliation grâce à une croissance compensatoire efficace, sans que sa reproduction en soit affectée. Cette forte tolérance à l’herbivorie est maintenue chez les populations introduites, malgré la faible pression des ennemis naturels dans la zone d’introduction. En condition de stress hydrique, l’ambroisie produit une biomasse racinaire supérieure aux espèces présentes dans les communautés qu’elle envahit. De plus, les différences dans les valeurs moyennes pour les traits mesurés suggèrent une occupation différente par l’ambroisie des niches écologiques disponibles. La comparaison en jardins communs de populations de l’aire d’origine avec des populations de l’aire d’introduction isolées et issues du foyer central d’invasion a montré que l’adaptation de l’ambroisie à son environnement reposait principalement sur la plasticité phénotypique plutôt que sur la différenciation des traits. Les études de génétiques quantitatives ont mis en évidence un potentiel évolutif élevé pour les traits liés à la germination. Les traits liés à la morphologie, à la phénologie et à la physiologie de la plante montrent une variance additive et une héritabilité plus faibles et donc un potentiel évolutif moindre. En revanche, la variation dans les normes de réaction indique un potentiel évolutif important de la plasticité phénotypique. La tolérance au stress hydrique et à l’herbivorie sont des facteurs qui potentiellement augmentent la capacité de l’ambroisie à coloniser une large gamme d’habitat. De plus, la plasticité phénotypique et le potentiel évolutif important peuvent favoriser une augmentation ou un déplacement de la niche écologique de l’espèce et ainsi favoriser l’expansion de son aire de répartition / Understanding of the mechanisms behind the success of the invasive species is essential to manage current biological invasions and to prevent the risks of the futures ones. Using a conceptual framework integrating ecological and evolutionary processes, this work aimed to analyse the factors of the common ragweed colonization in France. First of all, the study of biotic and abiotic interactions has shown the ability of common ragweed to tolerate herbivory and water stress. Common ragweed is able to buffer defoliation through an efficient compensatory growth with no consequence on the reproduction. Herbivory tolerance has been maintained in introduced populations even if herbivory pressure is low in the introduction area. Under water stress conditions, common ragweed displayed higher root biomass than the other species present in the communities it invades. In addition, differences in mean trait values suggest different niche occupation by common ragweed compared with its companion species. Common garden experiments comparing native populations vs. invasive isolated and invasive core populations have shown that adaptation ability is mainly due to phenotypic plasticity rather than trait differentiations. Quantitative genetic studies suggest a high evolutionary potential for germination traits. Morphological, phenological and physiological traits exhibit lower standard genetic variation and lower heritability and thus a lower evolutionary potential. However, variation in reaction norms suggests a high evolutionary potential for phenotypic plasticity. Herbivory and water stress tolerance are factors that potentially increase the ability to colonize à large range of habitats. Furthermore, phenotypic plasticity and evolutionary potential may also favour an increase or a shift in species ecological niche and hence may favour the distribution range expansion

Les pressions anthropiques agissent en synergie du gène à l’écosystème, des régions polaires aux régions tropicales et induisent une érosion biologique telle, qu'elle est qualifiée de sixième extinction de masse.Ce constat pose la question de l’évolution de la biodiversité face aux changements environnementaux en cours. C’est dans ce contexte que s’inscrit ce travail de thèse focalisé sur les populations de surface (5 -60 m) de corail rouge, Corallium rubrum (Linnaeus, 1758), en Méditerranée Nord-Occidentale.Le corail rouge (Octocorallia, Coralliidae) est une espèce sessile à phase larvaire caractérisée par sa longévité importante, sa dynamique de population lente et son rôle structurant au sein des communautés de substrats durs de Méditerranée. Soumis à une importante pression de récolte, Corallium rubruma récemment subi deux évènements de mortalité massive concordant avec des anomalies thermiques positives, potentiellement liées au réchauffement climatique. La combinaison de ces deux pressions environnementales est donc susceptible d’affecter fortement l’évolution des populations de surface de cette espèce. Basé sur une approche intégrant génétique des populations et écologie de terrain, ce travail a pour objectif principal d’étudier les processus microévolutifs en jeu chez le corail rouge, de l’inter- à l’intra- populationel, afin de contribuer à l'amélioration de nos connaissances sur la biologie de cette espèce dans le contexte environnemental actuel.Ce travail de thèse élargit le champ de connaissances relatif à l’écologie de Corallium rubrum et fournit un ensemble d’outils et de données pour sa conservation face aux perturbations environnementales en cours.Il contribue, par la même occasion, à une avancée significative dans la compréhension de la biologie des organismes marins sessiles à phase larvaire.Il illustre notamment la pertinence d'approches mises place à des échelles spatiales réduites, pour répondre à des questions fondamentales sur l’évolution de ces organismes, souvent clés au sein de communautés sous pression / Anthropic pressures act synergistically from gene to ecosystems and from polar to tropical regions, inducing a strong biological loss, which is considered by many as the sixth mass extinction. The evolution of biodiversity facing the ongoing global change is thus an open question.The present study is focused on the shallow populations (5 - 60 m) of Corallium rubrum (Octocorallia,Coralliidae) in the North Western Mediterranean Sea. The red coral is a sessile and long-lived species with a larval phase, a slow population dynamics and an important structuring role in the Mediterranean hard substrates communities. This species faces a strong harvesting pressure, and recently underwent two massmortality events linked to positive thermal anomalies putatively due to ongoing climate change. These two pressures may have deep implications on the evolution of the shallow populations of this species. Using population genetics and field ecology, the main objective of this study was to define microevolutionary processes acting between and within red coral populations, to enhance our knowledge on the biology of this species facing the environmental changes. This work extends our knowledge concerning the ecology of Corallium rubrum, and provides new toolsand data for its conservation in the context of the ongoing global change. Moreover, this work improves our understanding in the biology of sessile marine organisms with a larval phase, illustrating for example the relevance of approaches conducted at fine geographical scales to address questions regarding the evolution of these organisms.

Lors de ce travail de thèse nous avons adopté une approche fonctionnelle de la dynamique forestière méditerranéenne. L'objectif principal est de comprendre comment les réponses fonctionnelles à la disponibilité de la lumière et aux interactions biotiques vont conditionner la régénération des trois principales espèces impliquées dans cette dynamique : Pinus halepensis, Quercus ilex, Quercus pubescens. Une première expérimentation en pots a été menée en conditions contrôlées afin de déterminer progressivement : les différences de stratégies d'acclimations à l'ombre du pin d'Alep et du chêne pubescent, les compromis fonctionnels et les limites ontogéniques et nutritionnelles de ces stratégies, et l'impact de l'allélopathie et de la compétition sur cette réponse à l'ombre. Une expérimentation de terrain a ensuite permis de créer un gradient d'éclaircie dans une pinède de pin d'Alep, pour comprendre les principaux effets positifs et négatifs de la canopée sur les facteurs abiotiques et le développement du chêne pubescent et du chêne vert à différentes échelles de temps. Les résultats obtenus montrent que le pin d'Alep présente une stratégie d'évitement de l'ombre par une forte réponse plastique qui implique des compromis fonctionnels, des coûts nutritionnels élevés, et un temps d'expression limité. Cette stratégie présente un désavantage dans le cas d'une régénération sous canopée. A l'inverse, le chêne pubescent montre une stratégie plus conservatrice grâce à une réponse plastique à l'ombre limitée, mais une forte sensibilité aux interactions plantes-plantes. En conditions naturelles, le chêne pubescent et le chêne vert en régénération présentent des réponses différentes au gradient d'éclaircie de la canopée, le chêne pubescent montrant cette fois ci une moins forte tolérance à l'ombre. Cette thèse permet de mettre en évidence les liens entre limites fonctionnelles de la plasticité phénotypique, tolérance à l'ombre, et réussite d'installation sous couvert forestier. / During this work we studied the Mediterranean forest dynamic through a functional approach. Our main goal consisted to know how functional responses to light availability and biotic interactions determine the regeneration of three main species involved in this dynamic : Pinus halepensis, Quercus ilex and Quercus pubescens.A nursery experiment was set up to determine specific shade acclimatation strategies of the Aleppo pine and the Downy oak, functional tradeoffs and nutritional and ontogenetic limits of these stratgies, and the competitive and allélopathic impact on the shade induced response.Then a field experiment was set up to make a light gradient in an Aleppo pins pinewood in order to know the main positive and negative canopy effects on abiotic factors and oak seedlings development at different scales of time. Results showed that Aleppo pine exhibits a shade avoiding strategy through a strong plastic response involving functional tradeoffs, high nutritional costs, and time-limited expression. This strategy is considered as maladaptive in case of regeneration under unovercome forest canopy. Reversly, the downy oak shows a more conservative strategy through a limited plastic response to shade but a strong vulnerability to plant-plant interactions. In field conditions, Quercus pubescens and Quercus ilex seedlings showed different responses to the canopy cover, with a fewer shade tolerance in Quercus pubescens. This work help to highlight relationships between functional limits of phenotypic plasticity, shade tolerance, and regenerative success in Aleppo pine understory.

En muchas áreas citrícolas del mundo el piojo rojo de California (PRC), Aonidiella aurantii (Hemiptera: Diaspididae), está considerado una plaga clave. En el Este de España se ha extendido durante las últimas décadas hasta cubrir una amplia extensión de cítricos. El control químico es difícil y frecuentemente es seguido de infestaciones recurrentes en poco tiempo, de la aparición de resistencias a diferentes productos usados para su control y de la eliminación de enemigos naturales en el campo. La mejora del manejo integrado y las técnicas de control biológico del PRC requieren conocer la composición de los enemigos naturales en cada zona climática, la fluctuación en su abundancia estacional, los niveles de parasitismo y depredación, como se distribuyen en la planta y como son afectados por el clima y el cambio climático. Aunque mucho se ha estudiado en laboratorio sobre los parasitoides Aphytis (Hymenoptera: Aphelinidae), los principales agentes de control del PRC, todavía no se conoce qué combinación de enemigos naturales consigue el mejor nivel de control en el campo, cómo varían los niveles de parasitismo a lo largo del año o cómo los parasitoides se distribuyen y compiten en el campo en relación con el clima. La acción de los Aphytis, ectoparasitoides, es complementada en muchas zonas citrícolas por los endoparasitoides Comperiella bifasciata y Encarsia perniciosi (Hymenoptera: Aphelinidae), los cuales pueden parasitar estadíos diferentes a Aphytis. Muy poco se sabe sobre el comportamiento y las respuestas biológicas bajo diferentes condiciones climáticas de estos endoparasitoides. Del mismo modo, el efecto de los depredadores sobre la población del piojo ha sido raramente estudiado. Actualmente, A. melinus, una especie introducida en el Este de España y el competidor superior, ha desplazado al parasitoide nativo A. chrysomphali de las zonas cálidas y secas ya que puede tolerar mejor las temperaturas cálidas del verano. / Sorribas Mellado, JJ. (2011). Biological control of California red scale, Aonidiella aurantii (Hemiptera: Diaspididae): spatial and temporal distribution of natural enemies, parasitism levels and climate effects [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/14794 / Palancia