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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

The evolution and ecological genetics of pupal color dimorphism in swallowtail butterflies (Lepidoptera: Papilioninae) /

Hazel, Wade Nelson, January 1980 (has links)
Thesis--Virginia Polytechnic Institute and State University. / Vita. Abstract. Includes bibliographical references (leaves 85-88). Also available via the Internet.
2

Daily Eclosion Patterns in Nymphalid Butterflies and Their Causes

January 2017 (has links)
abstract: The molt from pupae to adult stage, called eclosion, occurs at specific times of the day in many holometabolous insects. These events are not well studied within Lepidopteran species. It was hypothesized that the eclosion timing in a species may be shaped by strong selective pressures, such as sexual selection in the context of male-male competition. The daily timing of eclosion was measured for six species of nymphalid butterflies. This was done by rearing individuals to pupation, placing the pupa in a greenhouse, and video recording eclosion to obtain the time of day at which it occurred. Four species exhibited clustered eclosion distributions that were concentrated to within 201 minutes after sunrise and were significantly different from one another. The other two species exhibited eclosion times that were non-clustered. There were no differences between sexes within species. The data support a relationship between the timing of eclosion each day and the timing of mating activities, but other as of yet undetermined selective pressures may also influence eclosion timing. / Dissertation/Thesis / Masters Thesis Biology 2017
3

Effects of sulfuric-nitric acid solutions on mortality and development of Aedes triseriatus larvae and pupae

Fadely, Keith Richard January 1982 (has links)
Larvae of Ae. triseriatus mosquitoes were collected from treeholes on the Ball State University campus. These insects were raised to adulthood under laboratory conditions. Newly hatched larvae were raised in deionized water. One hundred twenty-five of instar 1 mosquitoes (group A) were placed into separate baby food jars containing deionized water. These jars were separated into five groups. The pH of the water in each group was adjusted to 3, 4, 5, 6 and 7 with a 70% to 30% sulfuric-nitric acid solution. Subsequent groups consisting of instar 2, 3 and 4 larvae and pupae (groups B, C, D and E respectively) were exposed to the same experimental treatment as that of group A. The effects of each of these pH levels on mortality and development was observed until the insects reached maturity or died.Larvae in water of pH 3 experienced a higher percentage of mortality than mosquitoes exposed to less acidic solutions. A decrease in mortality with age was observed. Mortality of insects in group A was greater than that of any other group. Mosquitoes in group D experienced the lowest mortality.Variations of developmental time for mosquitoes in pH 3 were probably due to high mortality. Developmental time was similar for all groups. Slight variations between these groups may have been due to natural fluctuations in development. The total average developmental time for Ae. triseriatus mosquitoes of this study was 11.12 days.
4

The effect of different water types on the survival and eclosion rate of submerged Lucilia sericata pupae

Robinson, Sakura 25 October 2018 (has links)
Blowflies (Diptera: Calliphoridae) are main colonizers of decomposing remains and any information on the influences of their lifecycle of growth and development are important to forensic entomologists when estimating postmortem interval during a medicolegal death investigation. Pupal survival of blowfly species, Lucilia sericata were studied at different developmental stages following pupation, white (0-12 hrs), young (24 hrs), medium (5 days), old (9 days) were submerged at various immersion intervals ranging from 1 hr to 120 hr (5 days) in different water types (fresh, salt, polluted, and drinking water). Control group (N= 100) were white pupae that were not submerged were also observed in order to compare the survival and eclosion rate. Two trials of the submergence process were conducted to observe the pupae survival. Data were analyzed using multiple logistic regressions in a 3-way interaction to determine if significant differences were seen between the water, time in water, and pupal stage. Dissolved inorganic nitrogen (DIN) of NH4+, NO2-, NO3-, and oP or DIP were analyzed to examine to determine if a correlation between the water types could be seen. DIN analyses exhibited similar NO2- + NO3- and NO3- in polluted and fresh water. The results show that as the pupae developmental age progressed, the pupae generally survived longer immersion intervals. The survival of white pupae decreased with the increase of submergence for all four water types, exhibiting a 100%mortality rate with pupae submerged longer than 24-36 hours. While pupae immersed in polluted water had similar survival rates in the white stage, the survival rate declined as the developmental age increased for pupae immersed in polluted water. Pupae immersed in salt and polluted water had earlier eclosion times when compared to other water groups, emerging at 36 hours from when the control group first emerged at day 12. Understanding the survival rate of submerged Lucilia sericata (Diperta: Calliphoridae) pupae will be potentially useful for criminal investigations by providing a better understanding of the survival of pupae submerged in different aquatic environments.
5

The evolution and ecological genetics of pupal color dimorphism in swallowtail butterflies (Lepidoptera: Papilioninae)

Hazel, Wade Nelson 24 September 2008 (has links)
Data bearing on the evolution, environmental control and genetic basis of pupal color dimorphism was presented or discussed for six species of swallowtail betterflies. Papilla glauces and P. cresphontes produce only brown pupae while P. polyxenes, P. troilus, Battus philenor and Eurytides marcellus produce both green and brown pupae. Natural pupation sites of the species were located and results were generally consistent with the hypothesis of Sheppard (1958) which relates the evolution of the environmentally-cued dimorphism to environmental variation. The relative importance of texture, color and photo-period as environmental cues controlling the expression of pupal color was investigated and the results were discussed in relation to differences in the pupation sites of the species. The genetic basis of pupal color was investigated in E. marcellus by selecting for an increase in the tendency of larvae to produce green or brown pupae. The results were found to be consistent with the genetic basis of the trait as proposed by Hazel (1977). It was concluded that the primary factor responsible for the evolution of the dimorphism and the environmental cues which control its expression is nature of the pupation sites that a species utilizes. / Ph. D.
6

Influencia da dieta irradiada sobre a longevidade e reproducao de Tribolium castaneum

FONTES, LUCIA da S. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:42:42Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:01:36Z (GMT). No. of bitstreams: 1 05233.pdf: 2598763 bytes, checksum: 32a56e411f1bece4104ab336f20a79b0 (MD5) / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
7

Influencia da dieta irradiada sobre a longevidade e reproducao de Tribolium castaneum

FONTES, LUCIA da S. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:42:42Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:01:36Z (GMT). No. of bitstreams: 1 05233.pdf: 2598763 bytes, checksum: 32a56e411f1bece4104ab336f20a79b0 (MD5) / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
8

Atividade inseticida do extrato bruto etanólico de persea americana (lauraceae) sobre larvas e pupas de aedes aegypti (diptera, culicidae) / Insecticidal activity of ethanolic crude extract of persea americana (lauraceae) on larvae and pupae of aedes aegypti (diptera, culicidae)

CARVALHO, George Harrison Ferreira de 25 February 2011 (has links)
Made available in DSpace on 2014-07-29T15:30:38Z (GMT). No. of bitstreams: 1 GeorgeHarrison.pdf: 311872 bytes, checksum: 1d09dab2e74a25c19bd15b1748b7bc46 (MD5) Previous issue date: 2011-02-25 / In the search for new alternatives for control of Aedes aegypti, in view of its resistance to chemical insecticides in use, research on plant substances has been increasing, due to be degradable and less toxic to vertebrates. The aim of this study was to evaluate the insecticidal effect of crude ethanol extract (cee) of bark of Persea americana Mill, on larvae and pupae of Ae. aegypti in the laboratory and field. After obtaining this cee was dissolved in dimethyl sulfoxide (DMSO), thus obtaining the test solution. For each test, and repetition, in both laboratory and field were used 100 larvae of the 1st, 2nd, 3rd and 4th instars and 100 pupae too. The same amount of larvae and pupae was used for the groups positive and negative controls, performed respectively with temephos at 1 ppm and 1.6% of the DMSO. Both the laboratory bioassays and field were conducted with key artificial urban tire, glass and plastic. The results showed the insecticidal activity of the cee P. americana larvae and pupae of Ae. aegypti, both in laboratory and field. There was 100% mortality of the larvae of the 1st and 2nd instars in the laboratory at a dose of 5 ppm and field at a dose of 10 ppm. In the laboratory the LC50 and LC90 were respectively 7.2 and 19.3 ppm for 3rd instar, 6.6 and 15.4 ppm for 4th instar and 93.6 and 158.7 ppm for pupae. Following the same order, in the field, the LC50 and LC90 were 27.8 and 51.3 ppm plows the 3rd instar, 23.8 and 46.9 ppm for the 4th instar and 145.3 and 261.9 ppm for the pupae. The most important factor of this study was the effect pupicida of P. americana, because it is very rare to find this effect on other products, both natural and synthetic.Tests acute oral toxicity in rats were conducted to cee this plant that proved to be nontoxic according to norms (Acute Toxic Class Method - OECD 423) for products of plant origin. / Na busca de alternativas ao controle do Aedes aegypti, em vista da resistência aos inseticidas sintéticos, a investigação de compostos vegetais vem se destacando, pela degradação mais rápida e menor toxicidade aos vertebrados. Assim, avaliou-se o efeito inseticida do extrato bruto etanólico (ebe) da casca de Persea americana Mill sobre larvas e pupas de Ae. aegypti. Após a obtenção do ebe este foi solubilizado em dimetilsulfóxido (DMSO), obtendo assim a solução-teste. Para cada bioensaio e repetição, tanto em laboratório quanto em campo foram utilizadas 100 larvas de cada estádio e 100 pupas. A mesma quantidade foi usada para os controles positivos e negativos realizados com o temefós (1ppm) e DMSO a 1,6%. Todos os bioensaios foram realizados com os principais criadouros artificiais urbanos, pneu, vidro e plástico. Os resultados obtidos demonstraram a atividade inseticida do ebe de P. americana em larvas e pupas de Ae. aegypti. Houve mortalidade de 100% das larvas de 1° e 2° estádios em laboratório na dose de 5ppm e em campo na dose de 10ppm. No laboratório as CL50 e CL90 foram, respectivamente, de 7,2 e 19,3 ppm para o 3° estádio, de 6,6 e 15,4 ppm para 4° estádio e de 93,6 e 158,7ppm para pupas. Seguindo a mesma ordem, no campo, as CL50 e CL90 foram de 27,8 e 51,3ppm ara o 3°estádio, de 23,8 e 46,9 ppm para o 4° estádio e de 145,3 e 261,9 ppm para as pupas. O fator mais importante deste trabalho foi o efeito pupicida de P. americana, pois é muito raro encontrar esse efeito em outros produtos, tanto naturais quanto sintéticos. Esses resultados são sugestivos de aprimorarem estudos químicos para identificação de compostos ativos. Testes de toxicidade oral aguda com ratos foram realizados com o ebe dessa planta que mostraram-se atóxico de acordo com as normas do (Acute Toxic Class Method - OECD 423) para produtos de origem vegetal.
9

The biology, behaviour and survival of pupating false codling moth, Thaumatotibia leucotreta (Meyrick) (Lepidoptera: Tortricidae), a citrus pest in South Africa

Love, Claire Natalie January 2015 (has links)
Control of the citrus pest, false codling moth (FCM), Thaumatotibia leucotreta Meyrick (Lepidoptera: Tortricidae) is crucial for the South African citrus industry. The economic losses and phytosanitary status of this pest, coupled with increased consumer awareness and demands, has created a need for effective, IPM-compatible control measures for use against the soil-dwelling life stages of FCM. Promising developments in the field of microbial control through the use of entomopathogenic fungi (EPF) and entomopathogenic nematodes (EPNs) have highlighted the need for research regarding pupation biology, behaviour and survival of FCM, as a good understanding of biology of the target organism is an important component of any biological control programme. The aim of this study was to improve the current understanding of FCM pupation habits through the manipulation of soil texture class, ground cover, shading, soil compaction, air temperature, and soil moisture in the laboratory. These findings would then be used to aid the biological control programmes using EPF and EPNs against FCM in the soil. Three soil texture classes (sandy loam, silt loam and silty clay loam) were obtained from orchards for use in the study. FCM larvae were allowed to drop into the soil of their own accord and the pupation behaviour that followed was then captured on film with pupae formed in the soil being kept in order to measure adult eclosion. In general, very few abiotic factors had a clear influence on FCM pupation. Larval wandering time and distance was short, but also variable between individuals. Distance did increase when soils were moist. Pupation depth was shallow, with pupal cocoons generally being formed on the soil surface. Depth of pupation was less than one centimetre for all abiotic conditions, with little burrowing into soil. Eclosion success was higher for sandier soils when these were dry and uncompacted, but the addition of both moisture and soil compaction increased FCM eclosion success. FCM was sensitive to desiccation when the soils were dry and temperature limits of 15 °C and 32 °C had a strongly negative impact on eclosion success. Preferences for particular abiotic conditions were limited to only certain moisture conditions when interacting with soil texture class and a preference for pupating in soil when it is available. Limited preference was found for particular soil textures despite this having a strong influence on eclosion success, but individuals did appear to pupate in close proximity to one another. Viable direct habitat manipulation for FCM control could not be identified. These results and all of the abiotic variables measured have important implications for EPF and EPN application, survival and persistence in the soil in order to improve the ability of these biological control agents to control FCM. These are discussed in each chapter.
10

Lutte contre les mouches tsé-tsé en Afrique de l’Ouest : optimisation de l’utilisation de la technique de l’insecte stérile / Control of tsetse flies in West Africa : optimizing the use of the sterile insect technique

Pagabeleguem, Soumaïla 15 December 2015 (has links)
En Afrique sub-saharienne, près de 10 millions de km2 de terres, les plus fertiles en productions fourragères et agricoles, sont infestées de mouches tsé-tsé limitant ainsi les initiatives de développement d’une agriculture durable. Les tsé-tsé transmettent des trypanosomes qui sont responsables des trypanosomoses animales et humaines africaines. En 2000, les Chefs d’Etats et de Gouvernements africains ont décidé de redoubler d’efforts pour lutter contre les mouches tsé-tsé et les trypanosomoses en créant la Pan African Tsetse and Trypanosomosis Eradication Campaign (PATTEC). Dans ce contexte, le gouvernement sénégalais a initié un programme d’éradication des glossines dans la zone des Niayes en utilisant une souche de Glossina palpalis gambiensis originaire du Burkina Faso. La présente thèse visait à optimiser l’utilisation de la technique de l’insecte stérile (TIS) en Afrique de l’Ouest pour lutter contre les glossines. Un dispositif de transport sur de longues distances de pupes matures a été développé et validé à partir de pupes mâles de G. p. gambiensis produites et irradiées à Bobo-Dioulasso, Burkina Faso et à Bratislava, Slovaquie (irradiation faite à Seibersdorf, Autriche) et transportées par voie aérienne jusqu’à Dakar, Sénégal. Le dispositif constitué d’une boîte isotherme et des packs S8 a permis de maintenir les pupes à une température de 10 ± 3°C et de les transporter pendant 2-3 jours jusqu’au centre d’émergence de l’ISRA, pour produire des mâles stériles utilisables pour la technique de l’insecte stérile. Un contrôle qualité a été réalisé sur un échantillon de 50 pupes prélevé dans chaque lot de pupes (minimum 2 lots par envoi) pour déterminer l’aptitude d’envol des mâles stériles et leur survie sous stress (à jeun). Le reste des pupes utilisé pour les lâchers sur le terrain a été considéré comme témoin. Le protocole qualité décrit permettra un suivi précis de la qualité des mâles stériles utilisés dans les programmes opérationnels d’éradication dans le cadre de la PATTEC. Un outil moléculaire de discrimination de mâles stériles lâchés et sauvages a également été développé à partir du gène mitochondrial COI (cytochrome oxydase) et a montré que les séquences COI des mouches lâchées (produites en insectarium) sont 100% identiques entre elles et différentes de celles des mouches sauvages. Par ailleurs, afin de déterminer les conditions optimales d’élevage de souches de G. p. gambiensis et de déterminer la souche qui sera la plus adaptée à tel ou tel environnement ou pays dans le cadre d’une lutte avec une composante lâcher de mâles stériles, les traits de vie (survie et fécondité) de trois souches de G. p. gambiensis (souches originaires du Burkina Faso (BKF), Sénégal (SEN) et souche introgressée (SENbkf) ont été évalués dans différentes conditions de températures et d’humidités relatives. La température optimale d’élevage en masse a été de 25 ± 1°C, 24,6 ± 1°C et 23,9 ± 1°C pour BKF, SENbkf et SEN respectivement. La variation de l’humidité relative (entre 40 et 75%) a eu très peu d’influence sur la survie et la fécondité. La souche BKF a mieux résisté à de fortes températures que les souches SEN et SENbkf, mais la température limite de survie a été de 32°C pour les trois souches. / In sub-Saharan Africa, nearly 10 million km² of land, the most fertile for animal and agricultural productions, are infested with tsetse flies limiting all development initiatives for sustainable agriculture. Tsetse flies transmit trypanosomes that cause human and animal african trypanosomosis, a debilitating disease of humans (sleeping sickness) and livestock (nagana). In 2000, the African Heads of State and Government decided to increase efforts to address the tsetse and trypanosomosis problem on the African continent and created the Pan-African Tsetse and Trypanosomosis Eradication Campaign (PATTEC). In this context, the Government of Senegal initiated a tsetse eradication program in the Niayes area using a Glossina palpalis gambiensis strain originating from Burkina Faso. The objective of this thesis was to optimize the use of the sterile insect technique (SIT) in West Africa in order to control the tsetse flies. A system to transport mature pupae over long distances has been developed and validated for male G. p. gambiensis pupae produced and irradiated either in Bobo-Dioulasso, Burkina Faso or in Bratislava, Slovakia (irradiation done in Seibersdorf, Austria) and then transported by air to Dakar, Senegal. The system, constituted of an insulated box and S8 packs, allowed the maintenance of pupae at a temperature of 10 ± 3°C and their transport during 2-3 days to the emergence center of ISRA, where they molted into sterile males which were used for the sterile insect technique.A quality control was carried out on a sample of 50 pupae from each batch (at least 2 batches per shipment) to determine the flight ability of sterile males and their survival under stress conditions (without feeding). The remaining emerging pupae were released in the target area of the eradication programme and were considered as control group. The described protocol for quality control will allow accurate monitoring of the quality of sterile males used in operational eradication programs organized in the context of PATTEC.A molecular tool to distinguish between sterile and wild males was also developed using the mitochondrial gene COI (cytochrome oxidase). We showed that COI sequences of released flies (reared in insectary) are 100% identical and different from those of wild flies.Furthermore, in order to determine the optimal rearing conditions for G. p. gambiensis strains and to identify the strain that would be the best adapted to a particular environment or country in the context of a control with an SIT component, life history (survival and fecundity) of three G. p. gambiensis strains (strains originating from Burkina Faso (BKF), Senegal (SEN), and an introgressed strain (SENbkf)) were investigated at different temperatures and relative humidity conditions. The optimal temperature for the mass-rearing was 25 ± 1°C, 24.6 ± 1°C and 23.9 ± 1°C for BKF, SENbkf and SEN respectively. The relative humidity ranging from 40 to 75% had very little influence on the survival and fecundity. The BKF strain resisted better at higher temperatures than the SENbkf and SEN strains but the temperature limit for survival was about 32°C for all three strains.

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