Bei der Eiablage müssen sich Pflanzen fressende Insekten wiederholt entscheiden, Eier auf Wirtspflanzen niedriger Qualität zu legen oder auf bessere Pflanzen zu warten. Diese Entscheidungen sind Fitness relevant, weil Larven sich je nach Wirt unterschiedlich entwickeln und weil Weibchen in diesem inter-temporären Optimierungsproblem sowohl zu wählerisch als auch nicht wählerisch genug sein und so nicht alle Eier bzw. Eier in zu geringer Qualität legen können. Meine Arbeit nutzt vier Ansätze um zu untersuchen, wie diese Entscheidungsprobleme entstehen und wie Weibchen diese strategisch lösen. Erstens benutze ich analytische Optimierungsmodelle um zu zeigen, dass ein evolutionärer Trade-Off zwischen Vermehrung und Überleben variierender evolutionär stabiler Ei- und Zeit-Limitierung führen kann, dass aber keiner dieser zwei Faktoren ignoriert werden darf. Zweitens stelle ich klar, dass in der Vergangenheit vorgeschlagene schematische Zeit- und Ei-Kosten der Eiablage sich nicht mit den wirklichen Selektionskräften auf die Ei-Anzahl decken und daher kein gutes Werkzeug zur Analyse von Eiablage-Strategien darstellen. Drittens zeige ich mit Optimierungs- und populationsgenetischen Modellen, dass räumliche Heterogenität in der Wirtsverfügbarkeit keine notwendige Bedingung für die Evolution von Generalismus ist, weil emergente Quellen-Senken Dynamiken die Anpassung der Insekten an marginale Habitate verhindern, wenn Migrationsraten nicht hoch sind. Viertens zeige ich an Agenten basierte Simulationen zum Beispiel des Aurorafalters, Anthocharis cardamines, dass der phänologische Spezialismus der Larven dieser Art den Eiablage-Generalismus der Weibchen zur Folge hat. Insgesamt zeigen diese vier Ergebnisse, wie nützlich theoretische Ansätze zur Untersuchung spezifischer Szenarios der strategischen Eiablage sein können und machen deutlich, dass die Evolution von Generalismus leichter aus zeitlicher denn aus räumlicher Heterogenität folgt. / Ovipositing phytophagous insects repeatedly face the decision problem of laying eggs on lower-quality host plants or waiting out for higher-quality ones. These choices carry fitness costs and benefits because larvae develop differentially on different hosts and because, in this inter-temporal optimization task, females may be too choosy and die before laying all eggs (i.e. become time-limited) or not be choosy enough and run out of eggs before their death (i.e. become egg-limited). This thesis employs four approaches to examine how oviposition decision problems arise and how they are strategically solved by female insects. First, I use analytical optimization models to show that a life-history trade-off between survival and reproduction can lead to varying evolutionarily stable levels of egg and time limitation, but that neither egg nor time limitation can be ignored in evolutionary analyses of oviposition. Second, I highlight that such schematic time and egg costs of oviposition as advocated in the past do not match the actual forces of natural selection on egg number as partitioned between egg and time limitation and therefore represent a less useful practice to analyze oviposition strategies. Third, I use optimality and population genetic models to show that spatial heterogeneity in host availability is not a sufficient condition for the evolution of generalism because emergent source-sink dynamics preclude adaptation of insects to marginal habitats unless migration rates are high. Fourth, I employ individual-based simulations built around the case study of the orange tip butterfly, Anthocharis cardamines, to show that this species’ larvae’s phenological specialism may drive the adult females’ oviposition generalism. All these findings show the usefulness of theoretical approaches to examine specific questions of strategic oviposition. Moreover, they demonstrate that evolution of generalism more likely results from resource unpredictability in time than in space.

La présent étude examine aspect de l'écologie chimique de la Pyrale du maïs (Ostrinia nubilalis, Hübner, Lepidoptera: Crambidae). L’isolement reproducteur des phérotypes et leur spécialisation à la plante hôte ont reçu une attention particulière. Toutes les expériences ont été conçues pour avoir des informations pertinents sur le plan écologique des signaux chimiques libérés ou perçu par la Pyrale du maïs pendant la période de reproduction. La plupart des travaux en cadre de cette thèse dans des conditions naturelles et en tenant compte de tous les traits comportementaux de la Pyrale. Premièrement, le paysage chimique du champ de maïs a été étudié pour connaître les signaux chimiques rencontrés par une femelle de Pyrale du maïs qui est à la recherche d’une plante hôte. Les mélanges des volatiles qui composent l'environnement olfactif du champ de maïs a été identifié et leurs rôles discutés selon la biologie et le comportement d’oviposition de la Pyrale du maïs.Deuxièmement, en tenant compte de la périodicité du comportement de la Pyrale du maïs nous avons étudié les modifications circadiennes des profils des volatiles libérés par les plantes individuelles du maïs et par le champ du maïs.Troisièmement, le fidélité d’hôte plantes de la Pyrale du maïs a été étudié. Les volatiles libérés par différentes plantes hôtes au moment de vol d’oviposition ont été identifiés et le comportement de ponte a été étudié dans le tunnel du vol.Quatrièmement, les signaux chimiques impliqués dans l'isolement reproducteur des phérotypes de la Pyrale du maïs a été étudié. Nous nous sommes concentrés sur la phéromone mâle produite par les pinceaux androconiaux et sur leur rôle dans le comportement de cour. / The present PhD study investigates the aspect of chemical ecology in the European corn borer (ECB, Ostrinia nubilalis Hübner, Lepidoptera: Crambidae): pherotypes reproductive isolation and host plant specialisation.All the experiences were designed to have ecologically relevant information about the chemical signals released or perceived by ECB moth during the reproduction period. Most of the work was conducted close to natural conditions and taking into account all the behavioural traits of ECB.First we investigated what can be the chemical landscape of maize field for host-seeking ECB moth. The whole volatile blends that make up the olfactory environment of maize field biotope was identified according to the ECB oviposition behaviour (Paper I). Secondly taking into account the diel periodicity of ECB behaviour we studied the diel changes of volatile profiles released from maize plant and from maize field (Paper II). Thirdly, we studied the process of host fidelity within the ECB host plants. The volatiles released from different host plants at the time of ECB oviposition flight were identified and the oviposition behaviour was studied in wind tunnel to evidence the host plant preferences of ovipositing females (Paper III). Fourthly, we address the question on assortative mating in ECB pherotypes and we investigated the chemical signals involved in the reproductive isolation in ECB pherotypes. We focused on the male pheromone produced by hairpencils and on courtship behaviour (Paper IV).

The production of cereals, especially maize, which is a staple food in sub-Saharan Africa, is challenged by pests and diseases. In addition, climate change will exacerbate the magnitude of these challenges and agriculture in general. Lepidopteran stemborers are major pests of cereal crops in sub-Saharan Africa. Two indigenous noctuids, Busseola fusca and Sesamia calamistis and one exotic crambid, Chilo partellus, occur as single and mixed-species communities infesting cereal crops in East and southern Africa. The composition of these communities however varies with altitude and over seasons. Interactions between the species especially when in combination, can affect the level of damage to cereal crops. The objective of this study was to describe the intraspecific and interspecific interactions between the three stemborer species when they make use of the same resources. This study involved field surveys in maize fields in major agro-ecological zones and also different experiments under greenhouse and laboratory conditions to describe the interactions between the species as well as the effect of temperature, species density and duration of the period of competition on outcomes of these interactions. Results showed that stemborer communities are composed of single and mixed species of B. fusca, S. calamistis and C. partellus, which varied with the different agro-ecological zones and also along altitudinal gradients. Temperature was the most important abiotic factor that influenced the composition of stemborer communities. However, infestation patterns varied with season. This study also showed that female moths of the three species did not avoid oviposition on plants that were previously infested by stemborers. Busseola fusca showed a high preference for heterospecific-infested plants, while C. partellus preferred conspecific-infested plants. Sesamia calamistis did not show a significant preference for one plant over the other. This study further showed that both intra- and interspecific competition characterise communities of these stemborer species which ultilise the same resources. Interspecific competition was stronger between the noctuids and the crambid than between the two noctuid species. Temperature had a significant influence on the competitive outcomes between the three species. Finally the study showed that densitydependent effects and the duration of the interactions are also important factors which influence the level of competitive outcomes between the species. Climate change is likely to influence the interactions and composition of stemborer communities. / PhD (Environmental Sciences), North-West University, Potchefstroom Campus, 2015

The production of cereals, especially maize, which is a staple food in sub-Saharan Africa, is challenged by pests and diseases. In addition, climate change will exacerbate the magnitude of these challenges and agriculture in general. Lepidopteran stemborers are major pests of cereal crops in sub-Saharan Africa. Two indigenous noctuids, Busseola fusca and Sesamia calamistis and one exotic crambid, Chilo partellus, occur as single and mixed-species communities infesting cereal crops in East and southern Africa. The composition of these communities however varies with altitude and over seasons. Interactions between the species especially when in combination, can affect the level of damage to cereal crops. The objective of this study was to describe the intraspecific and interspecific interactions between the three stemborer species when they make use of the same resources. This study involved field surveys in maize fields in major agro-ecological zones and also different experiments under greenhouse and laboratory conditions to describe the interactions between the species as well as the effect of temperature, species density and duration of the period of competition on outcomes of these interactions. Results showed that stemborer communities are composed of single and mixed species of B. fusca, S. calamistis and C. partellus, which varied with the different agro-ecological zones and also along altitudinal gradients. Temperature was the most important abiotic factor that influenced the composition of stemborer communities. However, infestation patterns varied with season. This study also showed that female moths of the three species did not avoid oviposition on plants that were previously infested by stemborers. Busseola fusca showed a high preference for heterospecific-infested plants, while C. partellus preferred conspecific-infested plants. Sesamia calamistis did not show a significant preference for one plant over the other. This study further showed that both intra- and interspecific competition characterise communities of these stemborer species which ultilise the same resources. Interspecific competition was stronger between the noctuids and the crambid than between the two noctuid species. Temperature had a significant influence on the competitive outcomes between the three species. Finally the study showed that densitydependent effects and the duration of the interactions are also important factors which influence the level of competitive outcomes between the species. Climate change is likely to influence the interactions and composition of stemborer communities. / PhD (Environmental Sciences), North-West University, Potchefstroom Campus, 2015

Doctor of Philosophy / Department of Entomology / Ludek Zurek / The larval stages of Culicoides sonorensis Wirth and Jones, a confirmed vector of bluetongue and epizootic hemorrhagic disease viruses affecting ruminants in North America, have been observed to occur typically in animal waste enhanced muds. In this dissertation, I studied the larval development (first instar to adult stage) and oviposition (four-choice assays) of C. sonorensis on sterilized mud (autoclaved) enriched with manure of different farm animal species (dairy cattle, beef cattle, sheep, goats, pigs, horses, white-tailed deer, and chicken). In addition, to determine why only some manure-polluted sites are colonized by C. sonorensis even when they are in close proximity to each other, I examined the moisture levels and microbial concentrations (mud) and physicochemical characteristics (standing water) of a manure-overflow pond site producing C. sonorensis and compared them to nearby cattle stock pond site(s) that produced different Culicoides species. Finally, as the first step in examining the role of microbiome in various physiological functions of C. sonorensis and other suspected/potential vector Culicoides species, I assessed the bacterial communities in field-collected adult females of C. sonorensis, C. crepuscularis, C. haematopotus, and C. stellifer (Illumina sequencing of 16S rRNA gene). In larval development experiments, the proportion of adults emerged and development time to adult stage varied with manure type and its concentration present in the substrate. Mud supplemented with chicken manure did not support C. sonorensis development, mud enriched with white-tailed deer manure poorly supported midge development, while C. sonorensis development in mud enhanced with manure of sheep, goats, beef cattle, dairy cattle, pigs, and horses varied. In oviposition experiments, colonized females preferred to deposit eggs on substrates without animal manure over substrates with animal manure. In subsequent studies, the manure-overflow pond site that produced mainly C. sonorensis contained significantly higher total aerobic culturable bacteria, pH, salinity, total dissolved solids, and conductivity levels than cattle stock pond sites that produced different Culicoides species. Finally, bacterial composition of field-collected C. sonorensis adult females comprised mainly of the phyla Proteobacteria and Firmicutes, while the majority of bacterial taxa identified from C. crepuscularis, C. haematopotus, and C. stellifer belonged to Proteobacteria. An unidentified bacterial genus (related to Tumebacillus), Propionibacterium, and Curvibacter were detected commonly across all four midge species. These results suggest that manure of several farm animal species can contribute to C. sonorensis development in the field. However, oviposition preferences remain uncertain, as colonized females appeared to show aversion to animal manure, which is in contradiction to the typical presence of C. sonorensis larvae in animal waste enhanced muds. Nonetheless, variations in microbial and/or physicochemical conditions in the larval habitats likely play a role in the differential emergence of C. sonorensis from various manure-polluted sites. Moreover, some bacterial taxa are associated commonly with C. sonorensis and other suspected/potential vector Culicoides species. Future studies are needed to examine oviposition preferences of field-collected females, life history traits of adults emerging from various manure-enriched substrates, developmental requirements of larvae, and the role of microbiome in various physiological functions of the host including vector competence for orbiviruses.

Comprendre comment les processus de transmission non génétique comme la transmission sociale influencent l’évolution comportementale des espèces est une problématique importante en biologie de l’évolution. Cette thèse cherche à appréhender les mécanismes de diffusion et de maintien d’une information au sein d’un groupe par l’étude de la transmission sociale d’un choix de site d’oviposition chez Drosophila melanogaster. Le premier volet de cette thèse met en évidence l’existence d’une transmission du choix de site de ponte entre des femelles démonstratrices possédant l’information et des femelles observatrices naïves ainsi qu’à déterminer le processus d’apprentissage social sous-jacent. Le transfert de l’information sociale du choix d’oviposition se fait par le biais d’interactions directes entre les démonstratrices et observatrices. L’analyse de ces interactions par une méthode de vidéo tracking révèle l’existence d’un transfert de l’information bidirectionnel : plus les observatrices et les démonstratrices interagissent plus les observatrices acquièrent le choix d’oviposition et plus les démonstratrices le perdent. L’acquisition d’une information personnelle de la part les démonstratrices n’induit pas systématiquement sa transmission sociale aux observatrices suggérant que les deux processus sont dissociés. Le deuxième volet vise à comprendre dans quels contextes l’information sociale est employée et comment un individu réalise la balance entre l’utilisation des informations sociales et personnelles présentes dans son environnement. L’influence du groupe est examinée sur l’efficacité de la transmission par l’étude de paramètres tels que le ratio entre démonstratrices et observatrices, la taille du groupe, ou la présence d’une variabilité génétique. Les drosophiles montrent une stratégie d’apprentissage social de « copier la majorité » pour choisir leur site de ponte. Lorsque deux informations sociales sont présentes et contradictoires, les drosophiles acquièrent celle en adéquation avec leur préférence innée. La taille du groupe n’influence pas la transmission sociale mais perturbe l’utilisation de l’information personnelle des démonstratrices. La présence d’une variabilité génétique au sein du groupe, issue du polymorphisme du gène foraging, montre des différences de stratégies d’apprentissage social entre les individus des différents variants alléliques. L’utilisation de l’apprentissage social est parfaitement intégrée dans les prises de décision des drosophiles laissant envisager sa prévalence dans le règne animal. Cette thèse permet d’apporter de nouveaux éléments sur les mécanismes d'adaptation du comportement basé sur les processus de transmission sociale et de dégager les futurs enjeux liés à son étude. / Understanding how the process of non-genetic transmission as social transmission influence species behavioral evolution is an important issue in evolutionary biology. This thesis seeks to understand the diffusion mechanisms and information maintenance within a group studying social transmission of a choice of oviposition in Drosophila melanogaster. The first part of this thesis show social transmission occurrence of oviposition choice between informed demonstrator and naive observer females and try to determine social learning processes underlying. Social information transfer of oviposition choice occurs through direct interactions between demonstrators and observers. Analysis of these interactions by a video tracking method reveals a bidirectional information transfer: the more observers and demonstrators interact, the more observers gain oviposition choice behavior and the more demonstrators lose it. Personal information acquisition of oviposition choice by demonstrators is not sufficient to induce its transmission to observers, observers social learning seems to require special conditions. The second part of this thesis analyzes how social context influence social information use and how an individual realizes the balance between social and personal information use. The influence of group composition on social transmission efficiency is studied through different parameters such as the ratio between demonstrators and observers, group size, and the presence of genetic variability within the group. Flies show a “copy the majority” social learning strategy in their oviposition site choice behavior. Females acquire social information matching with their innate preference in presence of two contradictory social information. Group size does not affect the social transmission but perturbs demonstrator’s use of personal information. Genetic variability within the group stems from foraging gene polymorphism shows differences of social learning strategy between allelic variants. This thesis highlights a social learning use fully integrated into individuals’ decision-making and brings new elements on behavioral adaptation mechanisms based on social transmission processes.

Zabrotes subfasciatus é considerado um dos principais predadores de sementes da espécie Phaseolus vulgaris, causando sérios prejuízos para esta espécie em armazenagem. Este trabalho teve como objetivo conhecer alguns dados do comportamento de oviposição das fêmeas de Z. subfasciatus (Coleoptera, Bruchidae) que ainda são desconhecidos. Foi estudada a oviposição de Z. subfasciatus em P. vulgaris, ao longo de toda a vida e em situações de privação do hospedeiro, logo após a emergência dos adultos, por períodos determinados de 1 a 10 dias. Foi utilizada apenas uma variedade de P. vulgaris: rosinha. O trabalho foi dividido em 2 fases, realizadas concomitantemente. Na primeira fase, foi estudada a variação da oviposição, ao longo do tempo de vida total das fêmeas, sem e com privação do hospedeiro, por até 10 dias, bem como a variabilidade entre as fêmeas dentro de cada grupo, observando as estratégias de cada uma delas no interior de cada grupo. Foram analisados vários parâmetros, como: número de ovos colocados diariamente, a longevidade, o período de oviposição e o número de ovos colocados por cada fêmea dentro de cada grupo. O número de ovos depositados por dia variou estatisticamente, sendo que o pico de oviposição na presença do hospedeiro (Grupo Controle) ocorreu entre o 2o e 5o dia de postura. A longevidade média foi de 11,1±1,8; o período de oviposição médio foi de 8,7±1,1 dias e o número de ovos colocados por cada fêmea ao longo da vida foi de 37,0±9,3. Nos Grupos em que houve privação do hospedeiro, também observou-se que o número de ovos colocados por dia foi diferente estatisticamente, sendo que o pico de oviposição ocorreu sempre no 1o. dia seguinte à privação, com exceção do nível 1, em que o pico ficou entre os dias 1 e 4 (após a presença do hospedeiro). A fecundidade máxima de cada grupo diminuiu, mas só foi diferente estatisticamente a partir do nível 6 (6 dias sem o hospedeiro), sendo que a média foi de 13,9±9,2 ovos, quando o tempo de espera foi de 10 dias. Isso sugere que em até 5 dias de privação, Z. subfasciatus consegue manter sua capacidade de postura, graças a uma boa retenção dos seus ovos e, a partir do 6o dia, há, provavelmente, uma reabsorção. A longevidade foi maior nos Grupos de Privação do hospedeiro a partir do nível 3, em relação ao Grupo Controle, mas o período de oviposição foi menor (4,3±4,6 dias no nível 10) a partir do nível 1, em relação ao Grupo Controle. O número de ovos colocados por todas as fêmeas, tanto no Grupo Controle como nos de Privação, não diferiu, indicando assim que não há variabilidade intraespecífica dentro de cada grupo. Na segunda fase, o objetivo foi comparar a distribuição dos ovos por grão, no Grupo em que não houve privação do hospedeiro (Controle) e nos Grupos em que houve privação por 2, 5, 8 e 10 dias, respectivamente. Foi constatado que as fêmeas privadas do hospedeiro por 5 e 8 dias apresentaram maior número de grãos com 4 ou mais ovos, no 1o dia de oviposição (1,4 grão em média), em relação ao Grupo Controle e as fêmeas que ficaram privadas do hospedeiro por 2 e 10 dias (0,8 grão em média). Quanto ao número de grãos com 1 ou nenhum ovo, observou-se que o Grupo Controle e os Grupos em que houve privação do hospedeiro por 8 e 10 dias apresentaram um maior número de grãos (3,2 grãos em média) em relação aos demais (2,1 grãos em média), no 1o dia de oviposição. E quanto ao número de ovos no grão com mais ovos, observou-se que ocorreu um maior número de ovos em todos os Grupos Privados (5,1 ovos/ grão em média), em relação ao Grupo Controle (1,9 ovo/ grão, em média). / Zabrotes subfasciatus is considered to be one of the main predators of Phaseolus vulgaris seeds, causing severe damage to this species during storage. The aim of the present study was to investigate some aspects of the oviposition behavior of Z. subfasciatus (Coleoptera, Bruchidae) females that are still unknown. The oviposition of Z. subfasciatus on P. vulgaris was studied along the entire life cycle of the parasite and in situations of host privation, right after the emergence of the adults, for periods of time ranging from one to ten days. Only one variety of P. vulgaris ("rosinha") was used. The study was divided into two parts carried out concomitantly. In the first part, the variation of oviposition along the total lifetime of the females was studied, with and without host privation up to ten days, as well as the variability among the females inside each group, with individual observation of the strategies of each insect. Several parameters were analyzed: number of eggs laid daily, longevity, oviposition period and number of eggs laid per female inside each group. The number of eggs laid per day varied significantly and the peak oviposition in the presence of the host (Control Group) occurred between the second and the fifth day after deposition. The mean longevity was 11.1 ± 1.8 days, the mean oviposition period was 8.7 ± 1.1 days and the number of eggs laid by each female along their lives was 37.0 ± 9.3. In the groups submitted to host privation the number of eggs deposited per day was significantly different, with peak oviposition occurring always on the first day after privation, except for level 1 where the peak was observed between the first and fourth days (after the presence of the host). The maximum fecundity of each group has reduced, but the difference was statistically significant only when level 6 (six days without the host) and higher levels were reached, the average being 13.9 ± 9.2 eggs when the waiting time was ten days. This suggests that, for up to five days of privation, Z. subfasciatus is able to maintain its oviposition capacity thanks to the good retention of its eggs. After the sixth day, however, reabsorption is likely to occur. The longevity of the groups submitted to host privation from level 3 to higher levels was longer than the longevity of the Control Group, but the oviposition period from level 1 to higher levels (4.3 ± 4.6 days at level 10) was lower than in the Control Group. The number of eggs laid by all females in the Control and Privation Groups did not differ, thus indicating that there is no intraspecific variability inside each group. In the second part of the experiment, the aim was to compare the distribution of eggs per grain in the group where there was no host privation (Control) and in the groups where privations of 2, 5, 8 and 10 days were imposed. The females kept under host privation for 5 and 8 days presented a larger number of grains with four or more eggs on the first day of oviposition (average of 1.4 grains) compared with the Control Group and with the females that were kept under host privation for 2 and 10 days (average of 0.8 grains). As regards the number of grains with one or no egg, the Control Group and the groups submitted to host privation for 2 and 10 days presented a larger number of grains (average of 3.2 grains) in relation to the others (average of 2.1 grains) on the first day of oviposition. As regards the number of eggs on the grains with a larger content of eggs, the number of eggs was larger in all the Privation Groups (average of 5.1 eggs/grain) in relation to the Control Group (average of 1.9 eggs/grain).

Orientador: Sergio Antonio De Bortoli / Resumo: No controle biológico, além dos microrganismos benéficos, devem ser também destacados parasitoides e predadores, sendo um bom exemplo deste último grupo, os crisopídeos (Neuroptera: Chrysopidae). O controle biológico aplicado, com a utilização de insetos predadores, como é o caso dos crisopídeos, está na dependência de alguns fatores, destacando-se dentre eles o conhecimento da biologia do inseto e a necessidade do domínio de uma técnica de criação eficiente e econômica em laboratório, que permita sua produção massal para subsequentes liberações em áreas de exploração agrícola. Já é de conhecimento que larvas de alguns crisopídeos são mantidas em laboratório, com boa eficiência, alimentadas com fontes de alimento obtidas de outras criações de insetos também mantidas em laboratório, dentre os quais podem ser destacados ovos de alguns lepidópteros. Ovos de Corcyra cephalonica (Stainton, 1866) (Lepidoptera: Pyralidae) são benéficos ao desenvolvimento de crisopídeos, produzindo adultos com alta viabilidade, porém há poucos relatos que estabelecem relação entre a espécie com Ceraeochrysa cincta (Schneider, 1851). Assim, este estudo teve por objetivo analisar o desempenho biológico de Ce. cincta alimentada com ovos de C. cephalonica, por três gerações, bem como fatores relacionados a técnicas de manipulação das diferentes fases deste predador na sua criação. Os ovos para os bioensaios com Ce. cincta foram coletados nas gaiolas de adultos com o auxílio de três instrumentos de corte,... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: In biological control, in addition to beneficial microorganisms, parasitoids and predators should also be highlighted. A good example of this latter group is the crisopids (Neuroptera: Chrysopidae). The biological control applied, with the use of predatory insects, as in the case of the crisopids, is dependent on some factors, especially the knowledge of insect biology and the need to master an efficient and economical breeding technique in the laboratory, allowing its mass production for subsequent releases in farm areas. It is known that larvae of some chrysopids are maintained, with good efficiency, with food sources obtained from other insect creations also kept in the laboratory, among which lepidopteran eggs can be highlighted. Corcyra cephalonica (Stainton, 1866) (Lepidoptera: Pyralidae) has also been shown to favor the development of chrysopids, producing adults with high viability, not being many reports relating this species to Ceraeochrysa cincta (Schneider, 1851). Thus, this study aimed to analyze the biological performance of Ce. cincta being fed with eggs of C. cephalonica, per three generations as well as factors related to phase manipulation techniques of this predator in its rearing. The eggs of Ce. cincta were collected from adult cages with the aid of three cutting instruments, two types of scissors, one long and one conventional, with a thin tip, and an apparatus made from a stylus blade adapted to a shaver. Ten samples were collected for each of the three... (Complete abstract click electronic access below) / Mestre

The association of olfactory information with a resource is broadly known as olfactory-based associative learning. From an ecological perspective, associative learning can reduce search time for resources and fine tune responses to changing biotic and abiotic factors in a variable environment, which in mosquitoes has implications for pathogen transmission and vector control strategies. The purpose of this dissertation was to examine the ability for olfactory-based associative learning across the major life history domains of mosquitoes. Six different experiments comprise this dissertation. The first was to evaluate the response of mosquitoes following conditioning to 5, 10 or 50% sucrose concentrations with individual level mosquito conditioning and testing and introduction of statistical analysis with binary logistic regression. Mosquitoes did not respond in a dose dependent manner with respect to positive response to target odors following conditioning. This effect appears to be related to the mosquitoes' prior exposure to sugar as those exposed to 10% sucrose before conditioning did not prefer 50% sucrose but significantly fewer chose 5% sucrose. In an evaluation of host associated odors and second blood meal choice by females using a dual-choice olfactometer no significant effects were observed. The lack of significance may have been due to insufficient sample sizes, problems with odor collection or physiological state of mosquitoes. Effects of predatory mosquitofish on larval development and female oviposition choice were evaluated by rearing in separated habitats under three different treatments followed by an oviposition choice assay. Females did not prefer their natal habitat or avoid predators but chose substrate that had contained mosquitofish fed conspecific larvae. Mosquitofish affected larval development with acceleration in treatments with mosquitofish fed Tetramin® and delayed pupation in treatments with mosquitofish fed conspecific larvae. Mosquito memory length was evaluated by conditioning and testing at six time intervals from colony and field populations at two ages. Younger mosquitoes showed higher levels of positive response after conditioning at all time intervals except the longest (24h). Finally the olfactory-based associative learning ability of Anopheles cracens was evaluated. Significant evidence for learning was observed in males but not females at a memory length interval of 24h.

Detailed knowledge about the habitat requirements of butterflies is vital for successful conservation. The aim of the present study was to examine the habitat requirements of the endangered butterfly Scolitantides orion on 15 sites in Östergötland, Sweden. The requirements of adults and ovipositing females were studied with regard to several environmental variables measured at three scales; small, transect and large scale. The probability of finding adults increased with decreasing tree cover at the small scale, and adult numbers increased with the proportion of bare rock at the large scale. In contrast, ovipositing females mainly responded to the small scale. The main finding was that females oviposited in areas with higher tree cover (< 70 %) than that preferred by dwelling adults (< 20 %). However, there was a greater probability of finding eggs when tree cover was less than 50 %. Furthermore, egg numbers on host plants increased with the number of leaves on the stem and with the proportion of surrounding bare rock or bare ground. At the transect scale, females oviposited in areas with a higher density of host plants. To conclude, S. orion predominately inhabits open areas with warm microclimatic conditions for dwelling and oviposition. To conserve this species, suitable areas containing nectar plants and high densities of host plants with large leaf numbers and surrounded by large proportions of bare rock or bare ground, should be preserved. The areas should be maintained by selective clearing at regular intervals to uphold canopy openness and heterogeneity.