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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Origin and evolution of social hybridogenesis in Cataglyphis ants: Origine et évolution de l'hybridogenèse sociale chez les fourmis Cataglyphis

Kuhn, Alexandre 29 May 2019 (has links) (PDF)
Hybridization and genetic introgression are significant evolutionary processes playing a keyrole in the adaptation and diversification of species. In desert ants of the genus Cataglyphis,some species have evolved a remarkable reproductive strategy, termed social hybridogenesis,that relies on a perpetual hybridization between two sympatric, yet genetically distinct lineages.The non-reproductive workers systematically result from mating between partners of differentlineages; in contrast, queens and males are both produced asexually by parthenogenesis.Consequently, workers are all interlineage hybrids, whereas reproductives are all pure-lineageindividuals. Although several studies have been carried out on the reproductive strategies ofCataglyphis desert ants, the origin and the mechanisms underlying social hybridogenesis in thegenus remain unclear.In this thesis, I first examined three aspects associated to the persistence of socialhybridogenesis using the ant Cataglyphis mauritanica as a model. (i) I showed that the tightcaste – genotype association stems from a strong genetic influence on female caste fate.However, some degree of phenotypic plasticity was retained in hybrid as well as pure-lineagegenomes, although not expressed in natural conditions. (ii) The genetic survey of a largehybridogenetic population of C. mauritanica reveals that the two lineages occur with equalfrequency. Furthermore, restricted dispersal and parthenogenetic production of queens result ina mosaic of clonal patches. In contrast, males disperse over patches, ensuring successfulinterlineage mating. (iii) To determine whether mating between partners from the same geneticlineage participate to queen production, I simulated genetic data under various rates of sexualvs. asexual queen production. I found that genetic diversity within each lineage fits with theoccurrence a few sex; however, the 100% clonality hypothesis could not be discarded.I then investigated the evolutionary origin of social hybridogenesis in Cataglyphis. Bycharacterizing the reproductive system of 11 Cataglyphis species, five new instances of socialhybridogenesis were discovered. Inferences from phylogenetic analyses, including thesespecies and all Cataglyphis species for which reproductive information was available, indicatedthat this reproductive system independently evolved multiple times in the genus Cataglyphis.Overall, the results of this thesis highlight the singularities of a hybridogenesic systemassociated to queen parthenogenesis, which may have facilitated the repeated evolution ofdependent-lineages in Cataglyphis ants. / L’hybridation et l’introgression génétique jouent un rôle majeur dans l’adaptation et ladiversification des espèces. Chez les fourmis du désert du genre Cataglyphis, certaines espècesont évolué une stratégie de reproduction remarquable, appelée hybridogenèse sociale, reposantsur l’hybridation systématique entre deux lignées génétiquement distinctes. Les ouvrières nonreproductricessont issues de l’accouplement entre des partenaires de lignées distinctes ;enrevanche, les reines et les mâles sont produits de façon asexuée par parthénogenèse. Lesouvrières sont donc toutes des hybrides des deux lignées, alors que les individus reproducteurssont de pure-lignées. Bien que plusieurs études aient analysé les stratégies de reproduction desfourmis Cataglyphis, l’origine et le fonctionnement de l’hybridogenèse sociale au sein du genrerestent obscurs.Dans cette thèse, trois aspects associés au maintien de ce système ont premièrement étéétudiés en prenant la fourmi Cataglyphis mauritanica comme modèle. (i) La forte associationentre génotype et caste des femelles est lié à une forte influence génétique sur le déterminismede la caste. Néanmoins, une certaine plasticité phénotypique est maintenue dans les génomeshybrides et pure-lignée mais elle ne s’exprime pas en conditions naturelles. (ii) L’analysegénétique d’une population hybridogène de C. mauritanica montre que les deux lignées sontéquifréquentes. De plus, une dispersion limitée des reines ainsi que leur production parparthénogenèse mènent à la formation d’une mosaïque de patches clonaux. A l’inverse, lesmâles dispersent d’un patch à l’autre assurant les accouplements interlignées. (iii) Afin dedéterminer si les accouplements intralignées participent à la production des reines, des donnéesgénétiques ont été simulées sous différents taux de reproduction sexuée et asexuée. Les résultatsmontrent que la diversité génétique au sein de chaque lignée correspond à une faible fréquencede reproduction sexuée, bien que qu’un scénario avec 100% de clonalité ne puisse être écarté.Ensuite, l’origine évolutive de l’hybridogenèse sociale chez les Cataglyphis a étéanalysée. L’étude des systèmes reproducteurs de 11 espèces de Cataglyphis a permis ladécouverte de 5 nouveaux systèmes hybridogènes. Des analyses phylogénétiques, basées surces espèces et sur toutes les espèces de Cataglyphis pour lesquels le système reproducteur a étéprécédemment étudié, indiquent que ce système reproducteur aurait évolué plusieurs foisindépendamment au sein du genre Cataglyphis.En conclusion, les résultats de cette thèse soulignent les singularités d’un systèmehybridogène associé à la parthénogénèse des reines, qui a pu faciliter l’évolution répétée delignées dépendantes chez les fourmis Cataglyphis. / Doctorat en Sciences / info:eu-repo/semantics/nonPublished
2

THE GENOMIC ARCHITECTURE OF REPRODUCTIVE SYSTEMS IN DROSOPHILA

Stanley, Jr., Craig Edward January 2017 (has links)
Reproduction is among the most dynamic and rapidly evolving genetic systems across sexual taxa. However, the evolutionary mechanisms that drive reproductive traits during the early stages of species divergence are relatively unknown. Using a systems-level, comparative functional genomics approach, I investigate the role of selection, drift, and genomic architecture in promoting the rapid divergence of reproductive systems in Drosophila. I develop a new comparative genomics database, flyDIVaS (Divergence and Selection in Drosophila), an updateable database for identifying patterns and processes involved in species conservation and divergence. I show that tissue-specific genes play a disproportionate role in driving species level divergence and, in particular, that genes specific to male reproductive tissue are among the most rapidly evolving. Using two deeply sequenced populations of Drosophila melanogaster, I reveal that adaptation is widespread among male-specific genes and identify local signatures of selection that have evolved in less than 500 years on sperm motility. In Drosophila mercatorum, a fruit fly capable of facultative parthenogenesis, I find recent signatures of protein changes involved with centrosomal and meiotic functions, and identify early genomic signatures of male degeneration. Among laboratory strains of Drosophila melanogaster, I identify adaptive signatures on neurogenic genes that have recently been domesticated during the last century . Finally, I explore the role of genomic architecture in shaping such reproductive functional systems by developing a novel hypothesis that rapid changes in behavior, such as those found in diverse mating preferences, is a function of the size of the neurogenome. The results presented in this dissertation point toward the importance of selection, drift, and genomic architecture in driving rapid functional change which, together, promote the generation of species diversity via the formation of reproductive barriers in early species divergence. / Biology
3

Conséquences et évolution de l’autofécondation : une approche expérimentale chez des gastéropodes hermaphrodites d’eau douce / evolutionnary consequences of selfing : an experimental evolution approach in freshwater snails

Noël, Elsa 14 December 2015 (has links)
Une grande partie des organismes hermaphrodites, qu’il s’agisse de plantes ou d’animaux, est capable de se reproduire par autofécondation, comme alternative à la fécondation croisée. Or les modèles théoriques prédisent un ensemble de conséquences évolutives importantes liées à l’autofécondation. La première prédiction est qu'une population pratiquant l'autofécondation est moins sensible à la dépression de consanguinité qu'une population à reproduction croisée, car une partie de la dépression a été « purgée », c’est-à-dire que les allèles délétères récessifs sont éliminés par la sélection naturelle plus facilement en autofécondation. Cette purge entraine en retour une sélection positive sur l’autofécondation. On attend aussi chez ces populations l’évolution de traits facilitant l’autofécondation (par ex., des fleurs fermées), ainsi qu’une réallocation de ressources de la fonction mâle vers la fonction femelle, en raison d’une sélection sexuelle réduite sur la fonction mâle. Une reproduction par autofécondation va aussi considérablement affecter la variabilité disponible en raison d’une taille efficace de population divisée par deux, augmentant les effets de dérive. Par ailleurs, la moindre efficacité de la recombinaison va augmenter la sensibilité aux interférences sélectives (sélection d’arrière-plan, balayage sélectif) et diminuer la probabilité de fixer plusieurs mutations avantageuses dans le même génome. En d’autres termes, l’autofécondation conduit à un fardeau génétique plus lourd, et diminue les capacités d'adaptation et l’efficacité de la sélection naturelle. On prédit donc que les espèces autofécondantes ont une probabilité d’extinction plus grande que les espèces allofécondantes – elles constituent un cul-de-sac évolutif. Ces prédictions ont pour l’essentiel été évaluées chez des plantes, voire ne l’ont pas été du tout. L’objectif de cette thèse est d’apporter des éléments permettant de les tester chez des animaux, les escargots hermaphrodites d’eau douce. Pour ce faire, nous avons opté pour une approche d’évolution expérimentale permettant de contrôler régime de reproduction, conditions environnementales et pressions de sélection. Notre modèle d’étude est Physa acuta, une espèce allofécondante qui est capable de se reproduire par autofécondation et nous avons des lignées expérimentales se reproduisant soit en allofécondation stricte soit alternant avec une génération d’autofécondation depuis 20 à 30 générations au laboratoire. La première expérience montre que non seulement la dépression de consanguinité est largement purgée en une dizaine de génération d’autofécondation, mais aussi que le temps d’attente (un trait positivement corrélé au taux d’allofécondation) a fortement diminué. Nous n’observons en revanche aucune réallocation sur la fonction femelle. La deuxième expérience dans laquelle nous avons comparé la réponse à la sélection sur un trait morphologique en autofécondation et en allofécondation montre qu’une population en autofécondation répond d’abord mieux car les allèles sont progressivement placés à l’état homozygote mais cet avantage s’épuise rapidement probablement à cause des interférences sélectives car en trois générations elles commencent à répondre plus lentement que la même population en allofécondation (le trait considéré était la forme de la coquille). Ces travaux apportent des éléments nouveaux quant à notre compréhension de l’évolution de l’autofécondation, et proposent des éléments expérimentaux novateurs quant à la moindre adaptabilité des espèces autofécondantes. / Many hermaphroditic organisms, either plants or animals, are able to reproduce by self-fertilization, at least alternatively with cross fertilization. Theoretical models predict several important consequences linked to this mating system. The first prediction is that a selfing population is less sensitive to inbreeding depression than an outcrossing one, because part of the depression can be « purged » meaning that the recessive deleterious alleles are easier to eliminate by natural selection under selfing. This purge creates a positive feedback to favour self fertilization. In these circumstances, we also expect the evolution of traits facilitating self fertilization (for example closed flowers) and a reallocation of resources from the male to the female function, because sexual selection is reduced in the male function. Self-fertilization also affects standing variation, as the effective population size is divided by two, enhancing the effects of drift. In addition, recombination becomes inefficient, increasing the extent of selective interference among loci (background selection, selective sweep) and decreasing the probability to fix several advantageous mutations in the same genome. In other words, self-fertilization decreases the adaptive potential and the efficiency of natural selection. We then predict that autogamous species have a higher probability of extinction, this is called the “dead end hypothesis”. Some of these predictions have been tested mainly in plants or not at all. The aim of this thesis is to test them in animals, using freshwater snails as model systems. To this end, we followed an experimental evolution approach using laboratory populations of Physa acuta a preferentially outcrossing snail able to reproduce by self-fertilization. These populations were maintained for 20 to 30 generations either under pure outcrossing or under alternating generations of outcrossing and selfing. In a first experiment we show that inbreeding depression is largely purged after only ten generations of selfing, but also that the waiting time, (a trait positively correlated to the outcrossing rate) decreased largely. We did not observe however any reallocation in favour of the female function. In a second experiment we compared the response to artificial selection on a morphological trait under selfing and outcrossing. We observed that when an outbred population switches to self-fertilization the response to selection is initially enhanced as alleles are progressively made homozygous. However this advantage is quickly offset by selective interference and after no more than three generations selfing populations start to respond to selection more slowly than outcrossing onesThis work brings new elements for the understanding of the evolution of mating systems, and provides empirical support for the lower adaptability of selfing species.
4

Taxonomické principy, reprodukční systémy,populační genetika a~vztahy mezi vybranými skupinami rodu Taraxacum (Asteraceae) / Taxonomic principles, reproductive systems, population genetics and relationships within selected groups of genus Taraxacum (Asteraceae)

Zeisek, Vojtěch January 2018 (has links)
Chapter 3 Summary - shrnutí English and Czech summaries (abstracts) of the thesis. 3.1 English abstract Genus Taraxacum (Asteraceae), having ∼60 sections and 2,800 species, is known for its complicated evolutionary relationships and taxonomy due to processes like frequent hy- bridization, polyploidization, asexual reproduction, clonality and low structural morpho- logical variability. Various taxonomical concepts and approaches are reviewed, evaluated and discussed from point of view of their ability to deal with such a complicated genera as is Taraxacum. Various processes responsible for the complicated situation within Taraxacum are discussed and reviewed. Section Dioszegia, comprising T. serotinum and its allies, are an exception because only sexuals are reported for all the members of this group. On the basis of the analysis of mi- crosatellite (SSRs) variation, distribution and morphology, we addressed problems related to their mode of reproduction, among-population relationships, taxonomy and within- population variation. As a rule, outcrossing was the dominant mode of reproduction, with one notable exception: T. serotinum subsp. tomentosum (≡ T. pyrrhopappum) was autogamous and not heterozygous. A taxonomic revision of sect. Dioszegia recognizes T. serotinum subsp. serotinum (including an aberrant...
5

Evolutionary transformations of the reproductive system in Eubrachyura (Crustacea: Decapoda)

Kienbaum, Katja 29 July 2019 (has links)
Die Brachyura umfassen ca. 7000 Arten. Die Variationsbreite ihrer morphologischen Merkmale spiegelt sich in den männlichen und weiblichen Reproduktionssystemen wider und machen sie zu einem herausfordernden Untersuchungsgegenstand. Obwohl sich zahlreiche Studien mit der Phylogenie der Brachyura befasst haben, fehlen eindeutige Ergebnisse. Manche Studien stützen sich weiterhin auf deren Teilung in die Podotremata, die Heterotremata und die Thoracotremata (die beiden letzteren bilden die Eubrachyura), die auf der Position der Gonoporen basiert. In dieser Arbeit wurden die männlichen Kopulations- und weiblichen Reproduktionssysteme von vier eubrachyuren Arten untersucht. Zur Analyse ihrer inneren Morphologie, wurden die Gonopoden in der ersten und zweiten Studie μCT-gescannt und 3D-rekonstruiert. Zusätzlich wurden in allen Studien rasterelektronenmikroskopische Untersuchungen angewendet, um Informationen über die Oberflächenstrukturen der Gonopoden zu erhalten. Alle Untersuchungen des weiblichen Systems wurden mit bewährten histologischen Methoden und Lichtmikroskopie durchgeführt. In der ersten und zweiten Studie wurde diese detaillierte Strukturanalyse durch 3D-Rekonstruktion ergänzt. Die Ergebnisse dieser Studien wurden in Zusammenhang mit der vorhandenen Literatur interpretiert, um Merkmale des männlichen und weiblichen Reproduktionssystems zu definieren und deren Potenzial für phylogenetische Untersuchungen zu diskutieren. Außerdem wird ein evolutives Scenario bezüglich der Transformation der hier vorgeschlagenen Merkmalszustände des weiblichen Reproduktionssystems diskutiert. Die Gonopoden sind wertvoll, um Artenzugehörigkeiten zu Brachyurengruppen zu identifizieren, sind aber für Untersuchungen großskaliger Brachyurenphylogenie ungeeignet. Einige der weiblichen Merkmale können ausschließlich heterotremen oder thoracotremen Weibchen zugeordnet werden. Die vorgeschlagenen Szenarien deuten darauf hin, dass einige dieser Charaktere mehrfach entstanden sind. / The Brachyura comprise approximately 7000 species. The variability of their morphological traits is reflected in the male copulatory and the female reproductive systems that make them a challenging object of investigation. Numerous studies addressed the brachyuran phylogeny but unambiguous results have yet to be presented. Some studies still rely on the division of Brachyura into the Podotremata, the Heterotremata and the Thoracotremata (the latter two forming the Eubrachyura) that is based on the position of the male and female gonopores. In this work, the male copulatory and female reproductive systems of four eubrachyuran species were investigated. In the first and the second study, the gonopods were µCT-scanned and 3D-reconstructed to analyse their internal morphology. Additionally, in all studies scanning electron microscopy was used in order to obtain information about the surface structures of the gonopods. All investigations of the female system were conducted using approved histological methods and light microscopy. In the first and second study, this detailed structural analysis was complemented by 3D-reconstruction. The results of these studies are evaluated in comparison with the existing literature in order to define characters of the male copulatory and female reproductive system and discuss their potential for phylogenetic investigations. Additionally, an evolutionary scenario of the transformations of the herein proposed character states of the female reproductive system is discussed. Without additional information from the female reproductive system, the gonopod morphology is valuable to identify species affiliations to certain groups but remains inconclusive for large-scale brachyuran phylogeny. Some of the female characters found in these studies can explicitly be assigned to heterotreme or thoracotreme females. The proposed scenarios suggest, that some, if not all of these characters probably have evolved multiple times.
6

Fatores associados ao sucesso reprodutivo de duas espécies coocorrentes de Jacaranda Juss. (Bignoniaceae)

Souza, Camila Vaz de. January 2019 (has links)
Orientador: Elza Guimarães / Resumo: Nessa tese estudamos duas espécies melitófilas de Bignoniaceae, Jacaranda caroba e J. decurrens, que coocorrem em formações savânicas de cerrado e que se mostraram modelos interessantes para explorarmos aspectos ecológicos e evolutivos relacionados à sua reprodução sexual, tendo em vista que apresentam uma complexa rede de interações com mutualistas e antagonistas. A sobreposição geográfica dessas duas espécies nos permitiu avaliar padrões de coexistência relacionados à dinâmica de florescimento, bem como seu anúncio floral relacionado à atração de visitantes florais mutualistas e antagonistas. Além disso, essa interação com mutualistas e antagonistas possibilitou averiguar o impacto da atuação de antagonistas que roubam néctar sobre a polinização de ambas as espécies e como os danos realizados por abelhas roubadoras de néctar interferem na sinalização visual e química aos polinizadores. Também avaliamos a exploração de néctar por diferentes grupos funcionais de visitantes florais de J. caroba e J. decurrens. Por fim, considerando que o sucesso reprodutivo está diretamente relacionado com a eficiência da polinização investigamos o sistema reprodutivo dessas duas espécies e o efeito da qualidade do pólen transferido entre flores associado ao comportamento dos polinizadores durante o forrageamento, buscando compreender os fatores intrínsecos relacionados à seleção mecanismos de autoincompatibilidade nas populações naturais amostradas. / Abstract: In this dissertation we studied two mellithiphilous Bignoniaceae species, Jacaranda caroba and J. decurrens, that co-occur in savanic cerrado formations. This is an interesting model to explore ecological and evolutionary aspects related to their sexual reproduction taking into account that they present a complex network of interactions with mutualists and antagonists. These species‟ geographical overlap allowed us to evaluate patterns of coexistence related to the flowering dynamics, as well as its floral display related to the attraction of mutualists and antagonists‟ floral visitors. Besides, their interactions with mutualists and antagonists allowed us to evaluate the impact of nectar-robbing antagonists on both species and how damage by nectar-robber bees interferes with visual and chemical signaling to pollinators. We also evaluated the nectar exploitation by different functional groups of J. caroba and J. decurrens floral visitors. Finally, considering that these species‟ reproductive success and the effect of pollinator behavior during foraging on the quality of the pollen that is transferred among flowers. Considering that species‟ reproductive success is directly related to the pollination efficiency, we investigated the reproductive system of these two species and the effect of the quality of the pollen transferred between flowers associated to the pollinators‟ behavior during the foraging, trying to understand the intrinsic factors related to mechanisms of self-in... (Complete abstract click electronic access below) / Doutor
7

Mecanismos reprodutivos em Physalis angulata l.

Chaves, Mariana Carvalho 29 September 2017 (has links)
Submitted by Jadson Francisco de Jesus SILVA (jadson@uefs.br) on 2018-07-11T22:03:00Z No. of bitstreams: 1 MARIANA CHAVES - Dissertacao Mariana Chaves_ DEFINITIVA.pdf: 1571122 bytes, checksum: 655c891bef9d1aa8432a75b67d4a75e7 (MD5) / Made available in DSpace on 2018-07-11T22:03:00Z (GMT). No. of bitstreams: 1 MARIANA CHAVES - Dissertacao Mariana Chaves_ DEFINITIVA.pdf: 1571122 bytes, checksum: 655c891bef9d1aa8432a75b67d4a75e7 (MD5) Previous issue date: 2017-09-29 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / Physalis angulata L. (Solanaceae) is a traditional medicinal species that can be found all over Brazil. The medicinal utility attributed derives from the production of complex substances of pharmacological interest as: vitaesteroids, fisalinas, flavonoids, steroids, fatty acids, carotenoids, ascorbic acid and alkaloids. For pharmaceutical production, the pharmaceutical industry requires a large amount of raw material, which would be very expensive and would generate significant impacts on the natural environment. In this way, it is necessary to develop breeding programs aimed at medicinal plants, in order to ensure the industrial production of special metabolites. In order to initiate the genetic improvement of a species it is necessary to obtain accurate information on several fundamental questions and one of them is the reproductive system. In this sense, the objective of this work was to carry out a study on the reproductive system of Physalis angulata, identifying the preferential crossing system through experiments of controlled pollinations, viability tests and pollen grain germination and floral visitors observations. All variables evaluated to estimate the preferential cross-breeding system of P. angulata indicated that this is a self-compatible species, and according to the egg pollen ratio it presents a facultative autogamous system. The dyes used to estimate pollen viability did not differ statistically. The pollen viability was high using the colorimetric method, however, there was no germination of the pollen tubes using the in vitro germination method, and further studies and adjustments of the culture medium were necessary. The hour factor influenced the viability of the pollen grains and reached 96% at 14 hours using the tetrazolium dye. The anthesis of the flowers of P. angulata lasted on average two days, they began the opening at 6 in the morning and the closure began at 14 o'clock in the field conditions; on the second day they reopen and close at the same time. In a greenhouse, the flowers opened at the same time, but the closure occurred around 5 pm and reopened the next day. The most frequent insects were of the order Hymenoptera (Apis mell?fera). / Physalis angulata L. (Solanaceae) ? uma esp?cie medicinal tradicional podendo ser encontrada em todo o territ?rio brasileiro. A utilidade medicinal atribu?da decorre da produ??o de subst?ncias complexas de interesse farmacol?gico como: vitaester?ides, fisalinas, flavon?ides, ester?ides, ?cidos graxos, caroten?ides, ?cido asc?rbico e alcal?ides. Para a produ??o de f?rmacos, a ind?stria farmac?utica requer uma grande quantidade de mat?ria-prima, o que seria muito dispendioso e geraria impactos expressivos no ambiente natural. Desse modo, faz-se necess?rio o desenvolvimento de programas de melhoramento voltados para plantas medicinais, visando assegurar a produ??o industrial de metab?licos especiais. Para iniciar o melhoramento gen?tico de uma esp?cie ? necess?rio obter informa??es precisas sobre v?rias quest?es fundamentais e uma delas ? o sistema reprodutivo. Nesse sentido, o objetivo desse trabalho foi realizar um estudo sobre o sistema reprodutivo de Physalis angulata, identificando o sistema de cruzamento preferencial por meio de experimentos de poliniza??es controladas, testes de viabilidade e germinabilidade dos gr?os de p?len e observa??es dos visitantes florais. Todas as vari?veis avaliadas para estimar o sistema preferencial de cruzamento de P. angulata indicaram que se trata de uma esp?cie auto-compat?vel, e segundo a rela??o p?len ?vulo apresenta um sistema aut?gamo facultativo. Os corantes utilizados para estimar a viabilidade pol?nica n?o diferiram estatisticamente. A viabilidade pol?nica foi alta utilizando o m?todo colorim?trico, entretanto n?o houve germina??o dos tubos pol?nicos utilizando o m?todo de germina??o in vitro, sendo necess?rios mais estudos e ajustes dos meios de cultura. O fator hora influenciou a viabilidade dos gr?os de p?len e alcan?ou 96% ?s 14 horas utilizando o corante tetraz?lio. A antese das flores de P. angulata durou em m?dia dois dias, iniciaram a abertura ?s 6 da manh? e o encerramento iniciou ?s 14 horas em condi??es de campo; no segundo dia reabrem e fecham no mesmo hor?rio. Em casa de vegeta??o, as flores abriram no mesmo hor?rio, mas o fechamento ocorreu por volta das 17 horas e reabriram no dia seguinte. Os insetos visitantes mais frequentes foram da ordem Hymenoptera (Apis mell?fera).
8

Morfologia de ovos, glândulas salivares e sistemas digestivo e reprodutor de Thaumastocoris peregrinus (Hemiptera: Thaumastocoridae) / Morphology of eggs, salivar glands and digestive and reproductive systems of Thaumastocoris peregrinus (Hemiptera: Thaumastocoridae)

Souza, Gabriely Köerich 26 July 2012 (has links)
Made available in DSpace on 2015-03-26T13:30:43Z (GMT). No. of bitstreams: 1 texto completo.pdf: 3355723 bytes, checksum: 62b4b87ccb61cdcbdc48ea8e77a66ee5 (MD5) Previous issue date: 2012-07-26 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The bronze bug Thaumastocoris peregrinus Carpintero & Dellapé (Hemiptera: Thaumastocoridae) is a pest of Corymbia and Eucalyptus species and there are no effective strategies for its control in commercial plantations. Biological data of insects of the family Thaumastocoridae are scarce, mainly with species of the subfamily Xylastodorinae. Morphological studies of eggs and digestive and reproductive systems can provide important information to control T. peregrinus. This study described the morphology of eggs, salivary glands, alimentary canal and reproductive systems of males and females T. peregrinus. Thirty females and fifteen males of T. peregrinus with different ages were obtained from a mass rearing facility in a room with temperature at 25 ± 2ºC, 70 ± 10% RH and 12 h photophase and prepared for analysis in a light microscopy. Eggs of T. peregrinus were obtained from the mass rearing facility, coated with gold and analyzed in a scanning electron microscope. Thaumastocoris peregrinus has a pair of bilobed principal salivary glands located between the segments of the meso- and metathorax. The wall of the lobes is formed by a single layer of cubic cells with some of them binucleate. Each gland has a main duct formed by a single layer of flattened cells. The alimentary canal of T. peregrinus has a short faringe followed by a long and thin esophagus that ends in a simple proventriculus and a short estomodeal valve. The midgut of T. peregrinus comprises an anterior dilated region without gastric cecae, a long and narrow middle region and a short and dilated posterior one. The hindgut is composed by a transition region with the midgut where the insertion of two pairs of Malpighian tubules occurs, a short ileum and a rectum with a folded epithelial wall, thick cuticle and flattened cells. The male reproductive system of T. peregrinus is formed by a pair of testa with three large and globular follicles isolated by a peritoneal sheath and two pairs of tubular mesadenian accessory glands well developed. The female reproductive system of T. peregrinus is formed by a pair of ovaries with two meroistic telotrophic ovarioles each. The ovarioles open into two long lateral oviducts that join into a short common oviduct. The common oviduct ends in a large bursa copulatrix with many folds and both are lined by a thick cuticle. Eggs with embryos at the stages of anatrepsis, katatrepsis and also after the dorsal closure were observed in the reproductive tract of T. Peregrinus females. Eggs of T. peregrinus are oval-shaped and flattened dorso-ventrally with a strong depression in the center and black colored. The chorion of the egg is divided into exochorion, endochorion, air layer and an inner chorionic layer. The outer surface of the exochorion lacks perforations or pores and showed shallow and elongated depressions that were more circular in the posterior region of the egg. The opercular opening is located laterally in the eggs of T. peregrinus with the neck region showing around 27 circular and concave projections that appear to be aeromicropyles, reduced chorionic rim and a narrow sealing bar internally. The operculum is elliptical and flattened and has the same texture as the rest of the corium, except for the smooth texture of the outer opercular region. Thaumastocoris peregrinus has digestive and reproductive systems similar to other species of Thaumastocoridae, but the external characteristics of the eggs of this species differ from others of the same family. Studies of a larger number of species can contribute to the knowledge and importance of the structures evaluated for identifications at the level of subfamily, genus or species and to understand the phylogenetic relationships of Thaumastocoridae. / O percevejo bronzeado Thaumastocoris peregrinus Carpintero & Dellapé (Hemiptera: Thaumastocoridae) é praga de espécies de Corymbia e Eucalyptus e não existem estratégias eficientes para seu controle em plantios comerciais. Dados biológicos de insetos da família Thaumastocoridae são escassos, sendo, principalmente,com espécies da subfamília Xylastodorinae. Estudos morfológicos dos ovos e sistemas digestivo e reprodutor podem fornecer informações para o controle de T. peregrinus. Este estudo descreveu a morfologia dos ovos, das glândulas salivares, do canal alimentar e dos sistemas reprodutores de machos e fêmeas de T. peregrinus. Trinta fêmeas e quinze machos de T. peregrinus com diferentes idades foram obtidos de criação massal em sala climatizada à temperatura de 25 ± 2oC, 70 ± 10% de UR e fotofase de 12 horas e preaparados para análise em microscópio de luz. Ovos de T. peregrinus foram obtidos da criação massal, metalizados com ouro e analisados em microscópio eletrônico de varredura. Thaumastocoris peregrinus possui um par de glândulas salivares principais bilobadas entre os segmentos do meso e metatórax. As paredes dos lóbulos são formadas por uma camada simples de células cúbicas sendo algumas binucleadas. Cada glândula possui um ducto principal formado por uma camada simples de células achatadas. O canal alimentar de T. peregrinus é formado por uma faringe curta seguida por um esôfago longo e fino terminando em um proventrículo simples e uma válvula estomodeal curta. O intestino médio de T. peregrinus é composto por uma região anterior dilatada e sem cecos gástricos, uma região mediana longa e estreita e outra posterior curta e dilatada. O intestino posterior é composto por uma região de transição com o intestino médio onde ocorre a inserção de dois pares de túbulos de Malpighi, um curto íleo e um reto com parede epitelial com grande quantidade de dobras, cutícula espessa e células achatadas. O sistema reprodutor masculino de T. peregrinus é formado por um par de testículos com três folículos grandes e globulares isolados por uma bainha peritoneal e dois pares de glândulas acessórias mesadênias tubulares e bem desenvolvidas. O sistema reprodutor feminino de T. peregrinus é formado por um par de ovários com dois ovaríolos cada do tipo meroístico telotrófico. Os ovaríolos abrem-se em dois ovidutos laterais longos que se unem em um oviduto comum curto. O oviduto comum termina em uma bursa copulatrix ampla e com diversas dobras e ambos são revestidos por uma cutícula espessa. Ovos com embriões nos estágios de anatrepsis, catatrepsis e após o fechamento dorsal foram observados no trato reprodutivo de fêmeas de T. peregrinus. A forma dos ovos de T. peregrinus é oval e achatada dorso-ventralmente com forte depressão no centro e coloração preta. O cório do ovo é dividido em exocório, endocório, camada de ar e camada coriônica interna. A superfície externa do exocório apresentou depressões pouco profundas e alongadas ou com formato mais circular na região posterior do ovo sem perfurações ou poros. A abertura opercular é localizada lateralmente no ovo de T. peregrinus com a região do colo apresentando em torno de 27 projeções circulares côncavas que parecem ser aeromicrópilas, borda corial reduzida e, internamente, uma faixa de vedação estreita. O opérculo é elíptico e achatado e apresenta textura semelhante ao restante do cório, exceto pela textura lisa da região mais externa. Thaumastocoris peregrinus possui sistemas digestivos e reprodutor semelhantes a outras espécies de Thaumastocoridae, mas as características externas dos ovos diferiram das demas espécies dessa família. Estudos de um maior número de espécies poderão contribuir para o conhecimento e importância das estruturas avaliadas para identificações em nível de subfamília, gênero ou espécie e se compreender as relações filogenéticas de Thaumastocoridae.

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