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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.
251

Avaliação de inseticidas para o controle de Aryrotaenia sphaleropa (Meyrick,1909) (Lepidoptera : Tortricidae) na cultura da videira e Efeitos secundários sobre Trichogramma pretiosum (Riley,1879) (Hymenoptera : Trichogrammatidae) / Evaluation of organic insecticides for the control Argyrotaenia sphaleropa (Meyrick, 1909) (Lepidoptera:Tortricidae) control in vineyards and secondary effects on Trichogramma pretiosum (Riley, 1879) (Hymenoptera:Trichogrammatidae).

Morandi Filho, Wilson José 13 April 2008 (has links)
Made available in DSpace on 2014-08-20T14:07:36Z (GMT). No. of bitstreams: 1 Dissertacao_Wilson_Morandi_Filho.pdf: 955803 bytes, checksum: 8c4ac7519c2845a0b5ede8d7f4ed0ebb (MD5) Previous issue date: 2008-04-13 / The Argyrotaenia sphaleropa (Meyrick, 1909) (Lepidoptera:Tortricidae) is often found damaging vineyards and other temperate fruit orchards, in the Serra Gaucha region. This work was conducted to study seasonal occurrence of A. sphaleropa adults in vineyards using sexual synthetic pheromone, the effect of commercial formulations of insecticides with emphasis on that allowed in the organic production (neem, natural piretro, pirolenhoso extract and Bacillus thuringiensis) to control A. sphaleropa and their effects on the egg parasitoid Trichogramma pretiosum adults. Based on weekly evaluation A. sphaleropa adults catched in Delta trap baited with synthetic sexual pheromone (Z11,13-14Ac + Z11,13-14Al + Z11-14Al in a ratio of 4:4:1, 1000μg/septum) during 2003/2004 season, it was observed four populational peaks in a Cabernet Sauvignon vineyards. The first population peak occurred in the beginning of October, the second in the beginning of February, the third occurred in middle of March and the forth in June. In the experiments conducted in the laboratory using grapevine leaves with artificial infestations of 3st to 4th instars) and in commercial vineyard, Bacillus thuringiensis var. kurstaki (Dipel DF 50, 75 and 100 g/100L), fenitrothion (Sumithion 500 CE, 150 mL/100L) and triclhorfon (Dipterex 500, 300 mL/100L) were efficient to control A. sphaleropa larvae reducing insect population upper to 90%. In laboratory, the insecticides Natuneem® (1500 ppm of azadirachtin/L) and the pirolenhoso extract (Biopirol 7 M®) (250 and 500 mL/100L) were not efficient in the control of A. sphaleropa when applied over grapevine leaves. Natural piretro (250 and 500 mL/100L) resulted in a mortality of 77,65 and 85,88% of insects, respectively 120 hours after application. Natuneem® (0,25 e 0,50%) incorporated to A. sphaleropa artificial diet increased larval phase, reduced larval and pupae viability producing males with a reduces lifespan. Biopirol 7M® in the concentration of 0,50% increased larval duration, reduced male longevity and the oviposition period without affecting fecundity. Baseding on the fertility life table, it was verified that Natuneem® and Biopirol®, both in 0,25 and 0,50% added to artificial diets increase modified the duration in days of a generation, the liquid tax of reproduction, the infinitesimal reason of population increase and the finite reason of increase of A. sphaleropa, when compared with diet without insecticides. Secondary effects of insecticides allowed in organic production (Natuneem®, natural piretro, Biopirol 7M® and Dipel DF®) and the phosphorous compounds used in grapevine (triclorfon and fenitrotion) were evaluated on adults of the egg parasitoid Trichogramma pretiosum following IOBC methodology. The experiments were conducted exposing adults (more sensible period) of T. pretiosum to dry pesticide residues sprayed on glass plates. It was observed that Natuneem® (500 mL/100L), Biopirol 7 M® (500 mL/100L) and Dipel DF® (100g/100L) had been innocuous (<30% parasitism reduction) while natural piretro (250 mL/100L) was classified as moderad harmful (80-99% of parasitism reduction). Natural piretro in the higher dose (500 mL/100L) showed a parasitism deduction in more than 99%equivalent to fenthiom (Lebaycid 500, 100. / Avaliação de inseticidas para o controle de Argyrotaenia sphaleropa (Meyrick, 1909) na cultura da videira (Lepidoptera: Tortricidae) e efeito secundário sobre Trichogramma pretiosum (Riley, 1879) (Hymenoptera:Trichogrammatidae). Orientador: Dr. Marcos Botton. Co-orientador: Dr. Anderson Dionei Grützmacher. A lagarta-das-fruteiras Argyrotaenia sphaleropa (Meyrick, 1909)(Lepidoptera:Tortricidae) é uma espécie freqüentemente encontrada danificando a cultura da videira e outras frutíferas temperadas na região da Encosta Superior do Nordeste do Rio Grande do Sul. Neste trabalho, foi estudado a variação sazonal de machos adultos de A. sphaleropa na cultura da videira com emprego do feromônio sexual sintético, o efeito de formulações comerciais de inseticidas com ênfase para os permitidos na produção orgânica (nim, piretro natural, extrato pirolenhoso e Bacillus thuringiensis) para o controle do inseto e seu efeito sobre o parasitóide de ovos Trichogramma pretiosum. Com base na avaliação semanal de machos de A. sphaleropa capturados em armadilha Delta contendo o feromônio sexual sintético (formulação Z11,13-14Ac + Z11,13-14Al + Z11- 14Al na proporção 4:4:1, impregnada em liberadores de borracha na dose de 1000μg/septo) durante a safra 2003/2004 foram observados quatro picos populacionais na cultura da videira cultivar Cabernet Sauvignon. O primeiro pico populacional ocorreu no início do mês de outubro, o segundo no início de fevereiro e o terceiro teve o acme em meados do mês de março sendo quarto no mês de junho. Em experimentos conduzidos em laboratório com discos de folhas de videira com lagartas de 3-4 ínstar e em pomar comercial de videira, observou-se que os inseticidas Bacillus thuringiensis var. kurstaki (Dipel DF 50, 75 e 100 g/100L) fenitrothion (SumithionÒ 500 CE, 150 mL/100L), e triclorfon (DipterexÒ 500, 300 mL/100L) foram eficientes no controle de A. sphaleropa, reduzindo a população em níveis superiores a 90%. Em laboratório, os inseticidas Natuneem® (1500 ppm de Azadiracta indica por litro) e o extrato pirolenhoso (Biopirol 7 M®) nas doses (250 e 500 mL/100L) não foram eficientes no controle de A. sphaleropa quando aplicados sobre folhas de videira enquanto que o piretro natural (250 e 500 mL/100L) resultou em mortalidade significativa, controlando o inseto em 77,65 e 85,88% respectivamente, 120 horas após a aplicação. O Natuneem® nas concentrações testadas (0,25 e 0,50%) incorporados à dieta artificial de A. sphaleropa provoca um aumento na duração da fase de lagarta, menor viabilidade das fases de lagarta e pupa e menor longevidade de machos enquanto que o Biopirol 7M® na concentração de 0,50% provoca aumento na duração da fase de lagarta, reduz a longevidade de machos e o período de oviposição sem afetar a fecundidade. Com base na tabela de vida de fertilidade verificou-se que a presença do Natuneem® e do Biopirol® dietas artificiais nas concentrações de 0,25% e 0,50% aumentaram a duração em dias de uma geração, a taxa líquida xiii de reprodução, a razão infinitesimal de aumento populacional e a razão finita de aumento de A. sphaleropa quando comparado com a dieta sem os inseticidas. O efeito secundário dos inseticidas (Natuneem®, piretro natural, Biopirol 7M® e Dipel DF®) e do organo-fosforado fenthiom foi avaliado sobre adultos do parasitóide de ovos Trichogramma pretiosum seguindo a metodologia da IOBC. Os testes foram conduzidos expondo-se os adultos (estágio mais sensível) de T. pretiosum a resíduos secos de pesticidas pulverizados sobre placas de vidro. Foi observado que o Natuneem® (500 mL/100L), Biopirol 7 M® (500 mL/100L) e Dipel DF® (100g/100L) foram inócuos (<30% de redução no parasitismo) enquanto o piretro natural na dose de 250 mL/100L foi classificado como moderamente nocivo (80-99% de redução no parasitismo) e nocivo (>99% de redução no parasitismo) na dose de 500 mL/100L equivalendo-se ao organo-fosforados.
252

Validation de la fonctionnalité des continuités écologiques en milieu urbain : approches plurispécifiques et multi-sites / Validation of the green infrastructure functionnality in urban landscape : multi-species and multi-sites approaches

Balbi, Manon 30 November 2017 (has links)
Le maintien de la connectivité à travers les paysages urbains, par nature très fragmentés, est un enjeu majeur de conservation de la biodiversité urbaine. On observe une prise en compte croissante de la connectivité dans les politiques d’aménagement du territoire, notamment avec l’établissement de la trame verte et bleue. De multiples outils cartographiques permettent de mettre en évidence les continuités écologiques (zones de forte connectivité), mais leur validation fonctionnelle fait souvent défaut. L’objectif de cette thèse est de valider les prédictions d’un modèle de chemin de moindre coût, sur plusieurs villes et avec différents modèles biologiques. Les espèces étudiées présentent différents modes et capacités de dispersion (vol, marche, reptation) et des exigences écologiques spécifiques (préférences pour les milieux herbacés ou boisés). Des protocoles de validation basés sur l’écologie du mouvement et la génétique du paysage sont appliqués, dans un souci de réplication (au sein de plusieurs villes) et de contrôle de la variabilité inter-individuelle. Nos résultats montrent des mouvements accrus au sein des continuités écologiques comparés à ceux observés en contextes paysagers prédits comme non connectés : les hérissons transloqués s’y déplacent sur des distances plus longues, plusieurs passereaux répondent à la repasse de chant sur de plus longues distances et les papillons de nuit montrent des taux de recapture beaucoup plus élevés. Par ailleurs, les analyses indirectes réalisées sur l’escargot petit-gris montrent une relation assez faible entre la différenciation génétique des populations et les modèles de connectivité. Ce travail fournit des arguments scientifiques pour soutenir la mise en place de continuités écologiques en milieu urbain. / Maintaining connectivity across urban landscape, intrinsically fragmented, is a major issue of urban biodiversity conservation. Connectivity is increasingly taken into account by policy and stakeholders, especially through the establishment of the blue-green infrastructure. Multiple mapping tools allow to detect ecological networks (highly connected areas), however their functionnal validation is often lacking. The objective of this study is to validate least cost path analysis predictions in several cities with different biological models. Studied species vary in terms of dispersal means and capacities (flight, walk, crawling) and habitat requirement (e.g. herbaceous or forested habitats). Several protocols based on movement ecology and landscape genetic are applied, focusing on replication (within and among cities) and control of inter-individual variability. Our results indicate that movement is increased in predicted ecological networks when compared with areas predicted as poorly connected: the translocated hedgehogs travelled longer distances, several passerine responded to song playback over longer distances, and moths showed increased recapture rates. Indirect analysis on the garden snail showed a weak relation between population genetic differentiation and connectivity models. This work provides scientific support for the establishment of ecological networks in urban landscapes.
253

Green Communication in IoT Networks Using a Hybrid Optimization Algorithm

Maddikunta, Praveen Kumar Reddy, Gadekallu, Thippa Reddy, Kaluri, Rajesh, Srivastava, Gautam, Parizi, Reza M., Khan, Mohammad S. 01 June 2020 (has links)
There has been a huge surge in the Internet of Things (IoT) applications in recent years. The sensor nodes in the IoT network generate data continuously that directly affects the longevity of the network. Even though the potential of IoT applications are immense, there are numerous challenges like security, privacy, load balancing, storage, heterogeneity of devices, and energy optimization that have to be addressed. Of those, the energy utilization of the network is of importance and has to be optimized. Several factors like residual energy, temperature, the load of Cluster Head (CH), number of alive nodes, and cost function affect the energy consumption of sensor nodes. In this paper, a hybrid Whale Optimization Algorithm-Moth Flame Optimization (MFO) is designed to select optimal CH, which in turn optimizes the aforementioned factors. The performance of the proposed work is then evaluated with existing algorithms with respect to the energy-specific factors. The results obtained prove that the proposed method outperforms existing approaches.
254

<b>Phylogenomics and species distribution models to infer evolutionary relationships, delimit species, and better understand lichen-host interactions in tiger moths</b>

Makani L Fisher (17656290) 16 December 2023 (has links)
<p dir="ltr">The lichen-feeding tiger moth tribe Lithosiini (Erebidae: Arctiinae) represent the largest radiation of invertebrate lichenivory. Caterpillars feed on lichen and as they feed, also sequester lichen polyphenolics, a behavior unique to these insects. The role of these compounds is believed to defend lithosiines against predators as larvae have been found to be protected against predators such as ants and moths to predators such as birds and bats. Experimental testing with controlled diets is necessary to fully make this connection, however little is known about host specifics for lithosiines. Furthermore, although lithosiines are monophyletic, the lack of a fully resolved phylogeny hampers investigation into many of the shallower level relationships, e.g. those among genera and species, within the group.</p><p dir="ltr">I addressed these knowledge gaps using the subtribe Cisthenina. Members of this group have been used to investigate predator-prey interactions and been included in morphological and molecular studies. Thus, while the group still needs attention, there is an ample amount of legacy loci data available for its members. I used these data to investigate the evolutionary relationships at the genus level, but to increase resolution in my analyses I additionally sampled taxa throughout the group with a recently developed anchored hybrid enrichment (AHE) probe set. I combined it with the legacy loci to both increase taxon sampling and resolution. I confirmed that trees made strictly from the legacy loci were unsuccessful and resulted in poorly supported relationships that made little sense. The addition of the AHE data greatly helped resolve relationships, however, there remained areas that were poorly supported and they appear to be genera with only a few loci. Thus, there is still room for improvement, but this offers a way for moving forward in lithosiine research, particularly to involve others who may have limited funding, equipment, and/or personnel and may only be able to afford legacy loci in diverse collaborations.</p><p dir="ltr">As the AHE probe set worked well with genus-level relationships I further attempted to use it in species delimitation of the notorious <i>Hypoprepia fucosa</i>-<i>miniata </i>species complex. Members of this group are varying shades of yellows, oranges and reds and have a convoluted taxonomic history. I gathered and organized over 4,000 specimens and using the AHE probe set found support for five distinct species. Interestingly, I used other morphological characters such as genitalia, but found no differences between species and a large amount of intraspecific variation. This suggests other courtship behaviors may be present and external morphology, i.e., color patterns, remain the best way to identify species. As part of this I am describing a new species and raising one from subspecies and as species are now readily distinguishable, they can be used for further investigations into lithosiines.</p><p dir="ltr">I used a member of this complex, <i>H</i>. <i>fucosa</i> to then evaluate the use of species distribution models (SDMs) to better understand their niche and how it relates to plausible lichen hosts. I evaluated 17 lichen species from two lichen genera, <i>Physcia </i>(13 species) and <i>Myelochro</i><i>a </i>(4 species)<i>. </i>These genera were selected based on previous feeding assays and the metabolites found in them have also been found in <i>H</i>. <i>fucosa </i>further suggesting caterpillars may feed on them. SDMs typically only use environmental factors to define and predict species niches. I compared the niches described by traditional SDMs to assess how similar they were, but I also investigated the use of lichens as biotic factors in the models. I assessed the influence each lichen had on the moth’s distribution found the niche of every lichen to be significantly different than that of the moth and their inclusion in SDMs of <i>H</i>. <i>fucosa </i>to improve model performance. This suggests <i>H</i>. <i>fucosa </i>caterpillars to be polyphagous, but to have some connection with these lichens. Further investigation with live specimens is needed, but these results support this as an effective way to describe lithosiine niches to better understand lichen feeding.</p>
255

The effects of gypsy moth defoliation and climatic conditions on radial growth of deciduous trees /

Naidoo, Robin. January 1997 (has links)
No description available.
256

Optimization of a mass-rearing system to produce codling moth, Cydia pomonella, for a Sterile Insect Release programme in South Africa

Stenekamp, Daleen 03 1900 (has links)
Thesis (PhD (Conservation Ecology and Entomology))--University of Stellenbosch, 2011. / ENGLISH ABSTRACT: Codling moth, Cydia pomonella, is a worldwide pest and of major economic importance to the South African pome fruit industry. Sterile insect release is applied as a component of area-wide integrated pest management and includes the mass-rearing, sterilization and the release of the sterile insects. For sterile insect release, the improvements of rearing methods in terms of the quality of the diet ingredients and the economical aspect of the rearing method are examined. The effect of genetically modified maize meal, containing the Bacillus thuringiensis gene, in an artificial medium for codling moth rearing, is determined. The use of even a small amount of Bacillus thuringiensis resulted in larval mortality and prolonged development. These results are detrimental to a mass-rearing facility and must be considered by any rearing facility that uses genetically modified maize meal if the insect is sensitive to the gene. An alternative to maize meal in the artificial medium was tested and whole wheat flour was considered to be a suitable replacement. Agar agar is an expensive gelling agent used in the artificial medium. An alternative for agar agar (Kelcogel, Elastigel and carrageenen) is tested and the biological effect on codling moth is determined. Factors such as mortality, pupal and moth weight, longevity, fecundity and development time were used as quality parameters. Results showed that Elastigel was a suitable replacement for agar agar, with bigger pupae and moths, higher fecundity and increased longevity. The economical advantage of the replacement is a 40.91% reduction of the diet cost. The other gelling agents tested also gave acceptable results and can be considered if shortages of agar agar or Elastigel occur. A new method of mass-rearing codling moth larvae in a closed rearing system using large trays placed in a ventilated box is designed. This method is more cost and space effective as a smaller area is needed to rear a large number of moths. The risk of diet contamination is less because of the closed environment and more economical and effective air handling. This is the first report of its kind to describe the mass-rearing of codling moth in a closed environment and the risks involved in using genetically modified maize meal in an artificial diet for the codling moth. These results should be incorporated into existing mass-rearing facilities or taking into consideration when designing new mass-rearing facilities. / AFRIKAANSE OPSOMMING: Die kodlingmot, Cydia pomonella, is van ekonomiese belang vir die Suid-Afrikaanse kernvrugte bedryf. Die steriele insek tegniek word gebruik as ‘n komponent in area-wye geïntegreerde plaagbeheer en sluit in die massa-aanteel, sterilisering en vrylaat van steriele insekte. Vir die steriele insek tegniek is die verbetering van die massa-aanteel van die kodlingmot in terme van kwaliteit van die dieet en die ekonomiese aspek van die aanteel metode ondersoek. Die effek van genetiese gemanipuleerde mieliemeel wat die Bacillus thuringiensis geen bevat, in ‘n kunsmatige voedselmedium vir die aanteel van kodlingmot, is bepaal. Daar is gevind dat die gebruik van selfs ‘n klein persentasie Bacillus thuringiensis in die mieliemeel, mortaliteit en ‘n verlengde lewenssiklus in kodlingmot veroorsaak. Die gevolge is nadelig vir ‘n massa-aanteel fasiliteit en behoort in ag geneem te word vir enige insek wat op ‘n kunsmatige medium, wat mieliemeel bevat, geteel word, mits die insek sensitief is vir Bacillus thuringiensis. ‘n Alternatiewe bestanddeel vir mieliemeel, volkoringmeel, word aanbeveel. Agar agar is ‘n duur verdikkingsagent wat in kunsmatige mediums gebruik word. ‘n Alternatief vir agar agar (Kelcogel, Elastigel en carrageenen) is getoets en die biologiese effek op die kodlingmot is bepaal. Faktore soos mortaliteit, papie en mot gewig, langlewendheid, vrugbaarheid en lengte van lewenssiklus was gebruik as kwaliteit parameters. Resultate het getoon dat Elastigel ‘n geskikte plaasvevanger is van agar agar, met groter papies en motte, groter vrugbaarheid en langlewendheid. Die ekonomiese gevolg van die plaasvervanger, is ‘n vermindering van 40.91% van die dieetkoste. Die ander verdikkingagente wat is getoets is, het aanvaarbare resultate gelewer wat noodsaaklik is indien daar ‘n tekort van Elastigel of agar agar ontwikkel. ‘n Nuwe metode van massa-aanteel van kodlingmot larwes is bepaal. Die metode behels ‘n geslote sisteem, waar groter aanteel bakke in ‘n geslote, geventileerde boks geplaas word. Die metode is koste en spasie effektief en ‘n kleiner area word benodig om ‘n groter aantal motte te lewer. Die risiko van kontaminasie van die dieet word verminder as gevolg van die geslote sisteem wat gebruik word en meer ekonomiese en effektiewe lugversorging word gebruik. Hierdie is die eerste verslag van sy soort wat die massa-aanteel van kodlingmot in ‘n geslote sisteem beskryf en wat die risiko aandui van geneties gemanipuleerde mieliemeel in ‘n kunsmatige medium vir die kodlingmot. Hierdie resultate behoort in ag geneem te word vir reeds bestaande massa-aanteel fasiliteite of met die ontwerp van nuwe massa-aanteel fasiliteite.
257

The nesting ecology of bumblebees

O'Connor, Stephanie A. January 2013 (has links)
Bumblebees have undergone dramatic declines both in Britain and further afield during the last century. Bumblebees provide a crucial pollination service to both crops and wild flowers. For these reasons, they have received a great deal of research attention over the years. However, the ecology of wild bumblebee nests and the interactions between nests and other species, particularly vertebrates has been somewhat understudied. This is largely due to the difficulty in finding sufficient nests for well replicated study and a lack of appropriate methods of observation. Here, methods for locating bumblebee nests were trialled. It was found that a specially trained bumblebee nest detection dog did not discover nests any faster than people who had received minimal instruction. Numbers of nest site searching queens provide a reliable indication of suitable nesting habitat (i.e. places where nests are more likely to be found). In order to investigate aspects of bumblebee nesting ecology wild nests were observed by filming or regular observations by either researchers or members of the public. Some buff-tailed bumblebee (Bombus terrestris) nests were collected and all the bumblebees were genotyped to identify any foreign individuals. A review of British mammalian dietary literature was conducted to identify those that predate bumblebees. Great tits (Parus major) were filmed predating bumblebees at nests and it was clear from the literature and observations that badger (Meles meles), pine martens (Martes martes) and hedgehogs (Erinaceus europaeus) predate bumblebee nests, as well as the wax moth (Aphomia sociella). No evidence for predation by any other vertebrate species was found. Behaviours recorded included parasitism by Psithyrus, apparent nectar theft and possible usurpation by true bumblebees, egg-dumping by foreign queens and drifting and drifter reproduction by foreign workers. These events may cause harm to colonies (for example, through horizontal transmission of pathogens, or exploitation of the host nest’s resources). Alternatively where for example, usurpation by true bumblebees, egg-dumping or drifting is successful, these alternative reproductive strategies may increase the effective population size by enabling a single nest to produce reproductives of more than one breeding female. These data found that wild buff-tailed bumblebees (B. terrestris) nests with a greater proportion of workers infected with Crithidia bombi were less likely to produce gynes than those with fewer infected workers. Gyne production also varied dramatically between years. There is a growing body of evidence that a class of frequently used insecticides called neonicotinoids are negatively impacting bumblebees. An experiment was conducted using commercial colonies of buff-tailed bumblebees (B. terrestris) which were fed pollen and nectar which had been treated with the neonicotinoid imidacloprid at field realistic, sub-lethal levels. Treated colonies, produced 85-90% fewer gynes than control colonies. If this trend is representative of natural nests feeding on treated crops, for example, oilseed rape and field beans or garden flowers, then this would be expected to cause dramatic population declines. In this thesis methods for locating bumblebee nests have been tested, new behaviours have been identified (for example, egg-dumping by queens and predation by great tits) and estimations for rates of fecundity and destruction by various factors have been provided. Doubt has been cast over the status of some mammals as predators of bumblebee nests and estimates for gyne production, nest longevity, etc, have been given. More work is needed, especially observations of incipient nests as this is when the greatest losses are thought to occur.
258

Modelling the proximal source of intercepted exotic insects

Guichard, Sylvain January 2009 (has links)
Biological invasions are major threats to any nation’s economy and biodiversity. To detect new biological incursions of some species biosecurity agencies deploy pheromone sentinel traps for targeted species at high risk sites such as airports, seaports and transitional facilities. A good example is the gypsy moth surveillance program in New Zealand. Following the detection of an incursion by an unwanted organism, ground-based searches to locate the source can be very expensive, but are essential to identify the introduction pathway and to increase the chances of success eradicating the unwanted organism. In such circumstances, the possibility of better targeting the search for the source of the incursion using a modelling approach is worthy of investigation A stochastic mechanistic model to hindcast moth flight from a recapture location to the release location was developed based on insect behaviour in response to wind and pheromones. The model was composed of two main processes, 1) downwind dispersal, assumed to result from an appetitive behaviour, indicated by an analysis of a previous mark-release-recapture experiment on painted apple moth (Teia anartoides, Walker) and, 2) anemotaxic dispersal inspired by pheromone anemotaxis theory but up-scaled from a fine-scaled behaviour model to a 2 m scale. A genetic algorithm was used to fit some model parameters. A specialised fitness function was developed to allow the genetic algorithm to identify parameters that resulted in models that reflected both the spread and density patterns in the trapping data. The resulting function allowed the stochastic model results to be compared with the inherently stochastic trapping data. The resulting individual based model simulates the spatio-temporal dispersal pattern of painted apple moth recorded during a previous mark-release-recapture experiment. While the proposed model is shown to have limitations with respect to accuracy and precision it is also demonstrated to greatly improve biosecurity incursion response capability, by more efficient targeting of search effort for the proximal source of an incursion.
259

Moth pollination, low seed set, and vestigialization of attractive floral traits in Abronia umbellata (Nyctaginaceae)

Doubleday, LAURA 05 September 2012 (has links)
Flowering plants display remarkable phenotypic diversity, especially in reproductive structures, much of which is thought to be associated with pollination by animals. Pollination syndromes are collections of floral traits (e.g. flower colour, shape, odour) that are associated with a plant attracting particular functional groups of animal pollinators. We explored the extent to which traits associated with the moth pollination syndrome translated into pollination by moths in the Pacific coast dune endemic Abronia umbellata and found mixed results: in one year of study, there was no difference in seed set by day- vs. night-pollinated inflorescences, but in another year of study, night-pollinated inflorescences set significantly more seed than those pollinated during the day. We integrate this work with tests of pollen and resource limitation of seed production and with seed set surveys of natural populations to address proximate and ultimate causes of low seed set, finding low rates of pollinator visitation, high pollen limitation of seed production in all populations studied, and no evidence of endogenous resource limitation of seed production. We propose that “excess” flowers may be functionally male, serving to increase outcross siring success. The transition from self-incompatibility and obligate outcrossing to self-compatibility and predominant selfing is the most common evolutionary transition among the flowering plants and traits associated with outcrossing may become reduced across such shifts, potentially through the action of natural selection, especially if pollinators are also herbivores, or if the signals that pollinators use to locate flowers are also used by herbivores. We examined the reduction of attractive visual and olfactory floral traits in A. umbellata across a shift from outcrossing to selfing and found a reduction of all floral traits considered. We found that floral volatile emissions were reduced more strongly than flower size or floral display (number of flowers per inflorescence), but there was no evidence of an ecological cost associated with conspicuousness: we did not find reduced leaf herbivory among selfers relative to outcrossers. / Thesis (Master, Biology) -- Queen's University, 2012-08-30 19:46:23.663
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台灣農業無形資產附加價值提昇之探討 – 蝴蝶蘭產業營運新模式 / Value added for agricultural intangible assets in Taiwan – new operational models of moth orchid industry

蘇春霖, Su, Chun Lin Unknown Date (has links)
臺灣農業有優良的傳統,曾經以優越的生產技術,良好的品質,在外銷市場上,屢創佳績。本文首先探討當前農業發展的困境,源自於過度注重生產導向思維,忽略產業鏈上下游息息相關的產業結構,忽略行銷通路的發展,忽略知識經濟中,創新服務的附加價值。 近年來,蝴蝶蘭產業揚名國際,博得蝴蝶蘭王國美譽。分析蝴蝶蘭產業的價值傳遞過程,發現台灣蝴蝶蘭產業,正逐漸步入早期傳統農業的後塵,策略發展以生產能力為核心。這個營運策略為擴張規模,增加產能,以期降低成本,在市場上以價格競爭為手段。對於一個產業而言,這是一個危險的訊號。 今以蝴蝶蘭產業為例,深究台灣農業是否可以從企業經營觀點,健全產業結構,發掘更多附加價值。這個問題的答案存在於以無形資產創價的觀念,以現有良好的生產技術為後盾,結合農業科技智慧財產、聯合行銷與品牌經營,是未來台灣農業應該努力發展的三大策略主軸。 在此一策略思維主軸下,許多創新事業模式可以發展,包括農業生物科技公司,品質認證公司,拍賣公司,行銷公司,溫室營建公司等,或為周邊產業,或為上下游,唇齒相依。農產業一如其他產業,應思考佔據產業關鍵地位,方能提升議價能力,擁有競爭優勢。這些創新事業的特色為科技運用,服務事業,重視品質,最終以品牌經營為依歸。活絡創新事業,將現代化科技與服務精神引入農產事業,這是一場無產經營的變革,成功關鍵在發揮合作精神與善用優質人力。創造的無形資產價值,有一天可以超越農產品本身的價格。 / Agriculture had helped Taiwan earn economic advance in the early time, but went in vain and into history without sustained development. What constrains agriculture itself is the production-centered mind setting. Recently, moth orchid export has become a rising star among other horticulture products. Through analysis of Taiwan orchid value chain, it is found that orchid industry is stepping into the same path of traditional agriculture practice. Individual orchid farmers focus on enlarging greenhouse coverage in order to reduce cost and to win a price-based war. Discussion is made to ask if business management can be integrated into Taiwan agricultural practice. With good field practice technique supporting, intellectual property protection of biotechnology, brand operation and cooperative marketing should be three main strategies for future development of Taiwan agriculture. Agriculture, just like other business operation, should develop strategy to gain advantage in key position to win competition advantages. The characters of these innovative operational models are applications of current technology, service oriented, emphasis on quality, and ends in good brand management. Taiwan orchid farmers should also realize only through cooperative efforts, they can prevail. In the future, agriculture should recruit quality human resource in all aspects including business management, technology, engineering and service. Value generation by new business models producing intangible assets are proposed and discussed.

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