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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.
131

Etologie a akustická komunikace kaloně egyptského (Rousettus aegyptiacus) / Behaviour and acoustic communication in Egyptian fruit bat

Vašíčková, Pavla January 2014 (has links)
Egyptian fruit bats were observed in Prague Zoo, where stable conditions are provided (year-round food supply, stable temperature and roosts). The colony has bimodal breeding cycle. Births are synchronized and occur on the turn of April and May and in September. The mating occurs throughout the year but there is an increase during lactation and in the period outside parturitions. There is no obvious pattern in cluster dynamics. Bats roost in four clusters (left, middle, upper right and lower right). The presence of clusters throughout the year is stable except upper right cluster. There are changes in the number of clusters and in the number of individuals inside each cluster. Fruit bats occupy approximately the same spots in clusters, however young individuals show the highest variability. An autogrooming is balanced throughout the year, there is no regular pattern in the observation period and even no increase after artificial twilight. From these activities a licking of wing membranes and fur are the most often. The mother cares for her young especially during lactation and weaning, while the care decreases with a development of the young. This is especially true for the licking of the wing membranes. An allogrooming is the most common between male and female during lactation and in the period...
132

Pohlavní systém a druhový koncept u heterothalických druhů Aspergillus v sekci Fumigati / Mating system and species concept in heterothallic species of Aspergillus section Fumigati

Dudová, Zuzana January 2014 (has links)
The aim of this study was to determine the species boundaries within the Aspergillus viridinutans species complex. The species belonging to this complex are predominantly soil- inhabiting organisms that are increasingly reported as opportunistic human and animal pathogens. A total number of 98 isolates from various substrates and countries was subjected to morphological, physiological and molecular analysis (calmodulin, β-tubulin, actin and RNA polymerase II subunit 2 gene) and mating experiments were provided on different media and temperatures. Some other heterothallic species from section Fumigati with unknown sexual state were analysed using similar method as well. Key words: Aspergillus viridinutans, Aspergillus turcosus, phylogenetic analysis, mating- type genes, anamorph, teleomorph, mating experiments, MAT1-1, MAT1-2
133

Phylogenetics and Mating System Evolution in the Southern South American Valeriana (Valerianaceae)

Gonzalez, Lauren A 13 August 2014 (has links)
Species of Valerianaceae in South America represent one of the best examples of rapid diversification on a continental scale. The phylogeny of Valerianaceae has received a lot of attention within the last 10 years, but relationships among the South American species are fairly unresolved. Results from previous studies have not been well resolved with traditional genetic markers, most likely due to its recent and rapid radiation. Species in this clade exhibit a variety mating systems and inflorescence types. For the first part of this research I used several traditional plastid markers, and 3 new low copy nuclear markers to better resolve the phylogeny and then explore mating system evolution within the clade. For the second part of this research I collected high-throughput “next-generation” genomic sequence data from reduced representation libraries obtained using genotyping-by-sequencing (GBS) protocols, along with several phylogenetic methods, to try to further resolve the phylogeny of this group.
134

Evolution des phéromones de Drosophiles et rôle dans l’isolement reproducteur / Evolution of Drosophila pheromones and their role in reproductive isolation

Bontonou, Gwénaëlle 25 March 2014 (has links)
Il existe chez D. melanogaster et D. simulans un polymorphisme des hydrocarbures mâles qui pourrait jouer un rôle dans la mise en place d’un isolement sexuel. Le 7-tricosène (7-T; C23:1) et le 7-pentacosène (7-P; C25:1) sont les phéromones principales des mâles. Elles interviennent dans le comportement de cour et varient en fonction des paramètres géoclimatiques. Cette thèse a pour objectif d'étudier le rôle des phéromones mâles sur l’isolement sexuel ainsi que les changements génétiques à l’origine de leur variation et de leur évolution. Un des volets de cette thèse porte sur des aspects physiologiques et comportementaux. Nous avons étudié l'impact de la température sur la synthèse des hydrocarbures mâles et l'influence du rapport 7-T/7-P sur la résistance à la dessiccation et sur la réceptivité des femelles de différentes populations de D. melanogaster et D. simulans. Nous avons observé un isolement sexuel significatif entre des souches 7-T et 7-P de ces deux espèces présentes au laboratoire depuis des décennies, ainsi qu'entre des lignées issues d'une même population soumises à une sélection artificielle. Il apparaît également que les souches synthétisant de grandes quantités de 7-P s’adaptent plus rapidement aux modifications importantes de température. La seconde partie de cette thèse consiste en la détermination et l'étude des gènes d’élongase pouvant être impliqués dans la synthèse du 7-T et du 7-P chez les mâles de D. melanogaster et dans une moindre mesure chez ceux de D. simulans. Les travaux réalisés nous ont permis de mettre en évidence qu’un gène, situé sur le chromosome II, joue un rôle majoritaire dans la synthèse du 7-P. / In D. melanogaster and D. simulans there is a male hydrocarbon polymorphism that may play a role in sexual isolation. The main male pheromones are the 7-tricosene (7-T C23: 1) and the 7-pentacosene (7-P, C25: 1). They are involved in courtship behavior and depend on geo-climatic parameters. The aim of this thesis is to study the role of male pheromones on sexual isolation and to better understand the genetic changes responsible for the variation and the evolution of male pheromones. The first part investigates the plasticity of CHCs in response to temperature and focuses on the role of 7-T and 7-P in resistance to desiccation and in sexual selection in D. melanogaster and D. simulans. In both species there was partial sexual isolation between 7-T and 7-P flies from wild-type laboratory strains and also from lines that have been artificially selected. Males with high levels of 7-P seemed to modify their CHCs profiles more quickly in response to temperature changes. The second part is the identification of elongase genes that might be involved in the synthesis of 7-T and 7-P in D. melanogaster and D. simulans males. A gene, located on chromosome II, could play a major role in the synthesis of 7-P in D. melanogaster.
135

Origine génétique et moléculaire, et rôle adaptatif d’un dimorphisme floral chez Nigella damascena L / A floral dimorphism in Nigella damascena L : genetic and molecular control, and adaptive significance

Gonçalves, Beatriz 12 December 2013 (has links)
Comprendre la diversité morphologique des fleurs passe par l'étude de son origine moléculaire et développementale et de ses conséquences fonctionnelles et écologiques. Le périanthe est composé d'organes stériles, sépales et pétales, qui jouent un rôle majeur dans le succès reproducteur des plantes pollinisées par les animaux du fait de leur fonction d'attraction.Cette thèse propose une approche multidisciplinaire visant à comprendre l'origine génétique et moléculaire de la diversité morphologique du périanthe et sa signification évolutive, à l'aide du modèle Nigella damascena L. Cette Renonculacée présente un dimorphisme spontané. La forme probablement ancestrale, trouvée en populations naturelles, a un périanthe bipartite composé de cinq sépales pétaloïdes et huit pétales nectarifères. Dans la forme variante, cultivée à des fins d'horticulture, les pétales sont remplacés par un nombre élevé d'organes allant d'une forme proche des sépales à une forme proche des étamines.La première partie de cette thèse est consacrée à l'étude de l'origine développementale, génétique et moléculaire du dimorphisme, par la caractérisation détaillée de la morphologie florale et de son développement dans les deux morphes dans le cadre d'une approche gène candidat. Par analyse d'expression et validation fonctionnelle, nous avons montré que le gène NdAP3-3 est responsable de l'ensemble des aspects du dimorphisme floral de N. damascena, ce qui suggère que ce gène joue un rôle dans l'identité du pétale mais aussi dans l'architecture du méristème, potentiellement via la régulation du nombre d'organes et de la frontière entre périanthe et étamines.La seconde partie de cette thèse concerne l'impact du dimorphisme floral sur le mode de reproduction des deux morphes et leur maintien potentiel. Nous avons caractérisé les stratégies reproductives et la valeur sélective des deux morphes en conditions naturelles dans des populations expérimentales. Le variant sans pétale est peu visité par les pollinisateurs, et se reproduit majoritairement en autogamie. L'analyse de la vigueur de ses descendants suggère une dépression de consanguinité. Par ailleurs, dans notre matériel, il semble que l'allèle donnant le phénotype sans pétale soit lié à un allèle augmentant la valeur sélective. A la lumière de nos résultats, nous discutons les conditions du maintien de ce polymorphisme. / Understanding flower diversity requires on one hand the study of the molecular and developmental origin of floral architecture, and on the other the study of the functional and ecological consequences of flower morphology. A great deal of that diversity can be found at the perianth level which comprises the sepals and petals, sterile and versatile organs that play a major role in the reproductive success of animal pollinated flowering plants through their attractive characteristics.This thesis is the result of a multidisciplinary effort to understand the genetic and molecular origin as well as the evolutionary significance of perianth diversity, using the Nigella damascena L. as a model. This Ranunculaceae species presents a rare naturally occurring floral dimorphism affecting perianth architecture. The putatively ancestral form found in natural populations has a well differentiated bipartite perianth composed of five petaloid sepals and eight nectariferous petals, while the perianth in the alternative apetalous mutant, cultivated for horticultural purpose, has no petals and but is instead composed of numerous organs showing a continuum of forms from outer sepal-like to inner stamen-like.The first part of this thesis was dedicated to the study of the developmental, genetic and molecular origin of this dimorphism, via a detailed characterization of floral morphology and development in both morphs, which laid a foundation for the interpretation of the results of a candidate gene approach. Using expression analysis and functional validation we showed that NdAP3-3 is fully responsible for the complex N. damascena floral dimorphism, suggesting that it plays a role not only in petal identity but also in meristem patterning, possibly through the regulation of perianth organ number and perianth-stamen boundary.The second half of this thesis focused on the impact of the floral dimorphism on the reproduction mode and evolutionary maintenance of the two morphs. We assessed reproduction strategies and reproductive success in the two morphs by studying a polymorphic experimental population in natural conditions. The absence of petals in the mutant form was associated with a qualitative drop in pollinator visitation which resulted in a shift towards selfing. The study of their progeny suggests that selfing had a negative effect on the descendant’s vigor via inbreeding depression. Additionally, in our material, the allele responsible for the apetalous phenotype seems to be linked to a favorable allele increasing fitness. We discuss the mechanisms of the dimorphism maintenance in light of these results.
136

Diversidade morfoagronômica e taxa de cruzamento natural em pimentas Capsicum chinense / Morpho-agronomic diversity and natural outcrossing rate in peppers Capsicum chinense

Shimano, Iris Satie Hayashi 13 December 2018 (has links)
Estudos sobre diversidade e sistema reprodutivo das plantas cultivadas são de fundamental importância para o planejamento e elaboração dos programas de melhoramento bem como para a conservação e uso de recursos genéticos. Este trabalho é composto por duas etapas em que se objetivaram em primeiro momento caracterizar morfoagronomicamente 40 acessos de pimenta (Capsicum spp.) do banco de germoplasma da Escola Superior de Agricultura Luiz de Queiroz da Universidade de São Paulo, gerando informações que subsidiaram a metodologia para a estimativa da taxa de cruzamento natural para acessos desta espécie. A caracterização foi realizada para 16 descritores, sendo observada alta diversidade para os caracteres de hábito de crescimento, forma da folha, altura de planta, cor da antera, posição do estigma, presença de manchas na corola, constrição anelar no cálice, cor do fruto maduro, forma do fruto, forma do ápice do fruto, superfície do fruto, presença de pungência, dias para florescimento, massa fresca, largura e comprimento de fruto. Foi verificado que dentre os 40 acessos, 85% pertenciam à espécie C. chinense, 10% apresentaram características tanto de C. annuum como de C. frutescens, e dois acessos foram identificados como C. baccatum. Análises multivariadas de Componentes Principais (PCA), Agrupamentos e Coordenadas Principais (PcoA), foram realizadas verificando-se a existência de variabilidade entre os acessos. O coeficiente de dissimilaridade variou de 0,015 a 0,818. A análise de agrupamentos resultou na formação de cinco grupos que separaram os acessos principalmente quanto ao formato e tamanho do fruto. Com base na análise da diversidade três acessos de C. chinense com características morfológicas divergentes, foram selecionados como genitores para a estimativa da taxa de cruzamento natural. Os três acessos foram dispostos em módulos contendo uma planta de cada genótipo e deixados a campo para a ocorrência de cruzamentos naturais. Hibridações artificiais foram feitas entre os acessos selecionados a fim de se obter híbridos para utilização como testemunhas na avaliação da ocorrência e direção dos cruzamentos por meio da observação da expressão de marcadores morfológicos. A taxa de cruzamento variou de 0% a 40,6%, indicando que a espécie C. chinense apresenta sistema reprodutivo misto cujas taxas variaram principalmente em função do genótipo. / Studies on the diversity and reproductive system of crop plants are important for plant breeding programs as well as for the conservation and use of genetic resources. This work is composed of two stages: the first stage aimed to characterize 40 accessions of pepper (Capsicum spp.) from the germplasm bank of the Luiz de Queiroz College of Agriculture, University of São Paulo, with morpho-agronomic traits, and generating information that subsidized the methodology of the second stage, estimating the natural outcrossing rate of this species. The characterization was carried out for 16 traits, with high diversity being observed for the traits of plant growth habit, leaf shape, plant height, anther color, stigma exertion, presence of spots on corolla, calyx annular constriction, fruit color at mature stage, fruit shape, fruit apex shape, fruit surface, presence of pungency, days to flowering, weight, width and length of the fruit. Among the 40 accessions, 85% belonged to the species C. chinense, while 10% showed characteristic of both C. annuum and C. frutescens, and two accessions were identified as C. baccatum. Principal Components multivariate analyses (PCA), cluster and Principal Coordinates analyses (PcoA) were performed showing the existence of variability between the accessions. The dissimilarity coefficient ranged from 0.015 to 0.818. The cluster analysis resulted in the formation of five groups of accessions that diverged mainly according to size and shape of the fruit. Based on the diversity analysis, three morphologically distinct accessions of C. chinense were selected as parents for estimating the natural outcrossing rate. The three accessions were arranged in modules containing one plant of each genotype and were left in the field for the occurrence of natural crosses. Artificial hybridizations were made between the selected accessions in order to obtain hybrids for use as testers in the evaluation of the occurrence and direction of crosses by observing the expression of the morphological markers. The outcrossing rates varied from 0% to 40.6%, indicating that C. chinense presents a mixed reproductive system, and that the outcrossing rates varied mainly due to the genotype.
137

Ocorrência de poliandria na broca-do-café, Hypothenemus hampei (Coleoptera: Curculionidae: Scolytinae) / Polyandry occurence in the coffee berry Borer, Hypothenemus hampei (Coleoptera: Curculionidae: Scolytinae)

Costa, Camila Moreira 29 January 2014 (has links)
Estudos relacionados ao sistema de acasalamento nos insetos permite a compreensão dos aspectos evolutivos do comportamento reprodutivo de uma espécie. Esses sistemas são classificados, geralmente, pelo número de parceiros sexuais de um indivíduo durante um período de acasalamento. Em fêmeas, pode ocorrer monogamia, quando a cópula for realizada com somente um macho e, poliandria, quando há ocorrência de múltiplas cópulas com machos diferentes ou com o mesmo macho (cópulas repetidas). Em espécies como a broca-do-café, Hypothenemus hampei, que passam a maior parte de sua vida (ovo a adulto) no interior do fruto de café e possuem ciclo multivoltino os estudos envolvendo o sistema de acasalamento são escassos. Portanto, este trabalho visou estudar o acasalamento da broca-do-café, avaliando se há ocorrência de poliandria e os possíveis efeitos de múltiplas cópulas e cópulas repetidas sobre a bioecologia da fêmea e sua prole. Os resultados revelaram pela primeira vez a ocorrência de poliandria em H. hampei. Foi observado um maior número de recópulas em fêmeas colonizadoras, quando comparado com as fêmeas em oviposição, sugerindo que a condição fisiológica da fêmea foi um fator decisivo no momento da recópula. Além disso, a duração da recópula foi menor nas fêmeas em oviposição do que em fêmeas colonizadoras. A fecundidade foi afetada negativamente pela poliandria, sugerindo a presença de um custo associado a realização de múltiplas cópulas. A longevidade não foi influenciada pelo sistema de acasalamento, demonstrando que a poliandria não influenciou o tempo de vida das fêmeas. A recuperação larva:adulto em H. hampei não foi influenciada pelo sistema de acasalamento. Por outro lado, a taxa de eclosão de larvas foi superior na condição de poliandria, comparativamente à monogamia. / Researches about insects mating systems are important to understand the aspects of reproductive behavior evolution. Mating systems are usually grouped according to the number of mates during mating. Insect females mating system are classified as monogamy when there is only one copulation per male while polyandry refers to multiple mating with different males or with the same male (repeated mating). There is a lack of researches dealing with mating systems in species like the coffee berry borer, Hypothenemus hampei, which spend most of its life cycle (egg to adult) inside of the coffee berry and has a multivoltine cycle. This research aimed to study the mating system of H. hampei females, verifying the existence of polyandry and evaluating the effects of the multiple and repeated mating on the bioecology of the female and its offspring. The current study showed for the first time the occurrence of polyandry on females of H. hampei. The number of remating in colonizing females was higher than in the females under oviposition, thus the female physiological condition is crucial on remating behavior. The copula duration was shorter in females under oviposition than in the colonizing females. Fecundity was negatively affected by polyandry suggesting the existence of costs associated with multiple mating by females. Longevity were not influenced by the mating systems, showing that polyandry does not affect female lifetime. Although egg hatching was superior in polyandry compared to monogamy, the larva:adult recovery rate in H. hampei was not affected by the mating system.
138

Estudos genéticos em populações naturais da Macaúba em Reservas Legais de assentamentos rurais no Pontal do Paranapanema / Genetic studies in natural populations of macaw palm in Legal Reserves of rural settlements at Pontal do Paranapanema

Coelho, Natália Helena Pesso 15 February 2017 (has links)
A espécie Acrocomia aculeata (Jacq.) Lodd. ex Mart. é uma palmeira nativa, popularmente conhecida como macaúba, que possui ampla utilização desde a indústria alimentícia até na produção de biodiesel. Para estudos genéticos, foram coletados e extraído DNA de 50 indivíduos da espécie em três assentamentos no Pontal do Paranapanema-SP (FU, PJ e GB) e em Amparo-SP (AM) toatalizando 200 amostras. Os objetivos do trabalho foram caracterizar a diversidade genética, a estrutura genética espacial (EGE) e o sistema reprodutivo da espécie no Pontal do Paranapanema. A diversidade genética foi caracterizada pelos parâmetros: número de alelos por loco (Â ), heterozigosidades observada (Ĥo) e esperada (Ĥe) e índice de fixação (F^ ). As estatísticas F foram utilizadas como parâmetro de diferenciação genética entre ( F^ ST) e dentro das subpopulações ( F^IS). A EGE foi realizada pela estimativa do coeficiente de coancestria (θ^xy ) entre pares de árvores em relação a posição espacial destas. As populações de macaúba estudadas apresentaram níveis relativamente altos de polimorfismo, pois dos nove locos utilizados obteve-se um total de 103 alelos, sendo que 34 alelos são privados. O Ĥo médio variou de 0,410 a 0,531; O Ĥe médio variou de 0,547 a 0,615. O F apresentou valores positivos e significativos (0,119, 0,173 e 0,276) nas médias de PJ, GB e AM, respectivamente. As estatísticas F mostraram 16,8% de diferenciação entre as populações, ou seja, a maior parte da diversidade genética se encontra dentro das populações. Apenas para a população FU a EGE não foi significativa, na população PJ foi significativa na distância de 810 m (θ^xy =0,0211), porém foi considerado sem significado biológico. Nas outras o θ^xy foi significativo nas distâncias de 38 m (θ^xy = 0,0182 a θ^xy = 0,0418) e 71 (θ^xy =0,0213 a θ^xy =0,0934) para GB e AM, respectivamente, indicando que indivíduos dentro destas distâncias possuem algum grau de parentesco. Os parâmetros para estudar o sistema de reprodução foram calculados pelo MLTR e foram utilizadas 246 progênies (20 mães) da população FU, obtendo os parâmetros t^m =0,97, t^s =0,928, t^m - t^s=0,042, r^s =0,1 e r^p(m) =0,015. O número efetivo de doadores de pólen foi 66,66, a porcentagem de meio-irmãos, irmãos de autofecundação e cruzamento, irmãos completos e irmãos de autofecundação foram 92,7%, 5,8%, 1,4% e 0,09%, respectivamente. O tamanho efetivo foi 3,10, a coancestria foi θ^ =0,134 e o número de matrizes foi m^ =48,29. A macaúba é uma palmeira alógama, não houve correlação significativa de paternidade e o número de matrizes para coleta de sementes deve ser pelo menos 15 sementes de 49 árvores. / Acrocomia aculeata (Jacq.) Lodd. ex Mart. is a native palm, also known as Macaw, which has widespread utilization in the food industry as well as for biodiesel oil production. Samples were collected and DNA was extracted from 50 adult individuals in each of the three rural settlements at Pontal do Paranapanema (FU, PJ and GB) and at Amparo-SP (AM), totaling 200 samples. The study aimed to characterize the genetic diversity, spatial genetic structure (SGS) and the mating system in the Pontal do Parapanema. Genetic diversity was estimated by number of aleles per locus (Â), observed (Ĥo) and expected heterozygozity (Ĥe), fixation index (F^). The F^ statistics were used as genetic differentiation parameter among and within subpopulations. The SGS was studied by coancestry coeficiente (θ^xy ) between pair of trees. The studied populations showed relatively high levels of polymorphism using nine microsatellites loci with a total of 103 alleles, where 34 of these are private. The average of Ĥo and Ĥe ranged from 0.410 to 0.531 and 0.547 to 0.615, respectively. The fixation index (F^) presented positive and significant values in average for PJ (0.119), GB (0.173) and AM (0.276), respectively. The genetic differentiation ( F^ ST) was 16,8%, so most of the diversity is within populations. Only in the FU population the SGS was not significant, was significant up to 810 m (θ^xy=0.0211) for PJ with no ecological meaning. This parameter (θ^xy) was significant at up to 38 m (θ^xy = 0.0182 a θ^xy = 0.0418) and 71 m (θ^xy =0.0213 a θ^xy =0.0934) for GB and AM, respectively, indicating that individuals within these distances are related. The parameters to study the mating system were calculated using MLTR with 246 siblings of open pollination of 20 maternal families trees of the FU population, showing values of t^m=0,97, t^s =0,928, t^m - t^s=0,042, r^s =0,1 e r^p(m) =0,015. The number of effective pollen donors was 66,66, the percentage of the pairwise half sibs self-half-sibs, full sibs and sef sibs were 92,7%, 5,8%, 1,4% and 0,09%, respectively. The effective size was 3,10, the coancestry was θ^ =0,134 and the number of matrices m^ =48,29. The macaw palm is an outcrossing palm, there was no significant correlation of paternity and the collection of seeds should be in at least 15 seeds from more than 49 trees to keep a high genetic diversity.
139

Influência da nutrição e temperatura na reprodução de representantes de Noctuidae, Crambidae, Tortricidae e Elachistidae / Influence of nutrition and temperature on the reproduction of species from Noctuidae, Crambidae, Tortricidae and Elachistidae

Milano, Patrícia 01 April 2008 (has links)
Este trabalho teve como objetivo verificar a estratégia reprodutiva de seis lepidópterospraga, os noctuídeos Anticarsia gemmatalis, Heliothis virescens e Spodoptera frugiperda (Noctuidae), Diatraea saccharalis (Crambidae), Gymnandrosoma aurantianum (Família) e Stenoma catennifer (Elachistidae), tendo como alvo principal o uso de recursos nutricionais na fase adulta para sustentar o processo de reprodução e o efeito da atividade de cópula e temperatura na reprodução dessas espécies. Apesar de todas as espécies apresentarem índice de ovigenia bem inferior a 1, indicando a maturação de oócitos no decorrer da vida adulta, apenas A. gemmatalis e H. virescens necessitaram de alimentação na fase adulta para sustentar o processo reprodutivo, enquanto as demais espécies se utilizam dos nutrientes armazenados durante a fase larval. A partir destes resultados, foram escolhidas duas espécies que apresentavam estratégias reprodutivas distintas. Uma que utilizava apenas os nutrientes armazenados na fase imatura, S. frugiperda, enquanto a outra necessitava adquirir nutrientes na fase adulta para a sua reprodução, A. gemmatalis, para se verificar o efeito da freqüência de cópula e de seus efeitos na fecundidade, fertilidade e longevidade de adultos com estratégias reprodutivas distintas. A freqüência de cópula afetou de forma semelhante a longevidade de ambas espécies, havendo redução na longevidade com o aumento no número de cópulas. Porém, a fecundidade de S. frugiperda mostrou correlação positiva com a freqüência de cópula, não sendo verificado nenhum efeito na fecundidade de A. gemmatalis. Machos de ambas as espécies podem contribuir de forma semelhante para a reprodução da fêmea, independentemente de sua experiência prévia. Assim, a reprodução de fêmeas que copularam com machos experientes (2 cópulas prévias) foi similar àquela de fêmeas acasaladas com machos virgens. No entanto, a duração da cópula aumentou com a experiência do macho, sendo a terceira cópula mais longa do que a primeira. A relação da temperatura (15, 20, 25, 30 e 35ºC) e freqüência de cópula também foi investigada para essas espécies, sendo observado que as temperaturas extremas (15 e 35oC) afetaram a freqüência de cópula de ambas espécies. Porém, a temperatura demonstrou afetar as interações entre o número de cópulas e demais atributos biológicos relacionados à reprodução apenas para S. frugiperda mantidas a 25ºC, onde o aumento no número de cópulas resultou em maior fecundidade. / This paper deals with the reproductive strategies of six lepidopteran species, considering the use of food sources in the adult stage and the effect of mating activity and temperature in the reproduction of those species. The lepidopteran species were: Anticarsia gemmatalis, Heliothis virescens, Spodoptera frugiperda (Noctuidae), Diatraea saccharalis (Crambidae), Gymnandrosoma aurantianum (Tortricidae), and Stenoma catenifer (Elachistidae). From this group two species with different reproductive strategies were selected: S.frugiperda, which uses the nutrients stored during the larval stage, and A.gemmatalis, which uses nutrients acquired in the adult stage. Then one verified the mating frequency and its effects on adult fecundity, fertility and longevity. For both species longevity decreased as the number of matings increased. Female reproduction was similar either when they mated with virgin males or non virgin males. However mating duration was different for the third mating was longer than the first one. The temperatures of 15º and 35ºC did affect the mating frequency of both species. The frequency of matings was positively related to fecundity but only for S.frugiperda. Also S.frugiperda at 25ºC presented higher fecundity with the increasing in the number of matings.
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Comportamento sexual da broca-do-café, Hypothenemus hampei (Ferrari, 1867) (Coleoptera: Curculionidae: Scolytinae) / Sexual behavior of coffee berry borer, Hypothenemus hampei (Ferrari, 1867) (Coleoptera: Curculionidae: Scolytinae)

Silva, Weliton Dias da 10 February 2010 (has links)
O estudo do comportamento sexual dos insetos abrange todos os eventos ocorridos desde a formação dos casais por meio do cortejo, até a separação dos mesmos após a cópula. Esses estudos são importantes e representam o primeiro passo em pesquisas que visam à elucidação de feromônios da espécie alvo. No caso da broca-do-café, Hypothenemus hampei (Ferrari), que é considerada mundialmente a principal praga do café, existe uma lacuna de informações sobre o comportamento sexual dessa espécie. Além disso, as pesquisas têm sido direcionadas para o uso de armadilhas contendo alcoóis (ex: etanol e metanol) visando o manejo dessa praga, mas com resultados conflitantes. Em razão disso, o objetivo do presente trabalho foi estudar o comportamento sexual de H. hampei, como suporte para estudos subseqüentes visando a elucidação do feromônio da espécie. As cópulas de H. hampei ocorreram em qualquer horário dentro de um ciclo de 24 horas. Embora em menor freqüência, 60% dos casais realizaram pelo menos uma cópula na idade de 0-24 horas, chegando a 100% dos casais nas demais idades. A maior atividade sexual foi observada nas idades de 48-72 e 72-96 horas, onde, nessa última, ocorreram 6,9 ± 0,47 cópulas por casal com duração de 2,04 ± 0,13 minutos cada. Os padrões comportamentais exibidos foram semelhantes a outros grupos de curculionídeos, com pré-cópula, cópula e pós-cópula. Os resultados indicaram ainda a presença de um feromônio produzido pelos machos mediando o acasalamento. A possibilidade de as fêmeas de H. hampei realizarem a recópula após sua saída dos frutos abre novas perspectivas sobre a viabilidade deste feromônio no manejo desta praga. / The sexual behavior study in insects includes all the events occurred since of pair encounter by means of courtship until their separation after mating. These studies are important and represent the first step of researches that aim to elucidate pheromones of target species. Regarding the coffee berry borer, Hypothenemus hampei (Ferrari), which is the most important coffee pest around the world, little is known about its sexual behavior. Furthermore, the researchers have been focused on the use of traps based on alcohols (e.g. ethanol and methanol) with aims of managing this pest, but its results are conflicting. For that reason, the aim of the present work was to study the sexual behavior of H. hampei, whose it will give support to subsequent studies about evaluation of pheromone this species. Daily mating rhythm of H. hampei occurred on any time of 24- hour cycle. Although at low rates, 60% of paired adults mated at least once when they were 0-24 hours, reaching 100% in older pairs. The highest sexual activity was observed in the ages of 48-72 and 72-96 hours, being in this last one the occurrence of 6,9 ± 0,47 matings/pair with a mean duration of 2,04 ± 0,13 minutes each. The pattern behavior displayed was similar to other groups of Curculionidae, with premating, mating and postmating. The results also indicated the presence of a pheromone produced by the males that mediates mating. The possibility of the H. hampei females recopulates after they leave the fruits opens new perspectives to investigate the viability of using this pheromone in management of this pest.

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