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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.
191

Diversity, composition and seasonality of wild bees (Hymenoptera: Apoidea) in a northern mixed-grass prairie preserve

Patenaude, Andrea M. 14 September 2007 (has links)
The objective of this study was to characterize the wild bee fauna of a managed mixed-grass prairie in southwestern Manitoba. Weekly sampling using two methods, sweep-netting and bee bowls, was conducted over two years (2005-2006) at three sites within the Yellow Quill Mixed-grass Prairie Preserve. Spatial and seasonal patterns in diversity indices, taxonomic composition and ecological composition of the bee fauna were identified and investigated in relation to sampling method, environmental conditions, and floral resource availability. A total of 7014 individual bees representing five families and 100 species were collected. Numerically, social nesters from the genera Lasioglossum and Bombus dominated, while mining species of Andrena represented the greatest species richness. Observed spatial and seasonal patterns in the abundance, diversity and composition of the bee community were strongly modified by sampling method, resource limitation in the second year and the presence of the exotic invasive plant leafy spurge (Euphorbia esula).
192

Diversity, composition and seasonality of wild bees (Hymenoptera: Apoidea) in a northern mixed-grass prairie preserve

Patenaude, Andrea M. 14 September 2007 (has links)
The objective of this study was to characterize the wild bee fauna of a managed mixed-grass prairie in southwestern Manitoba. Weekly sampling using two methods, sweep-netting and bee bowls, was conducted over two years (2005-2006) at three sites within the Yellow Quill Mixed-grass Prairie Preserve. Spatial and seasonal patterns in diversity indices, taxonomic composition and ecological composition of the bee fauna were identified and investigated in relation to sampling method, environmental conditions, and floral resource availability. A total of 7014 individual bees representing five families and 100 species were collected. Numerically, social nesters from the genera Lasioglossum and Bombus dominated, while mining species of Andrena represented the greatest species richness. Observed spatial and seasonal patterns in the abundance, diversity and composition of the bee community were strongly modified by sampling method, resource limitation in the second year and the presence of the exotic invasive plant leafy spurge (Euphorbia esula).
193

The ecology and population genetics of a complex of cryptic bumblebee species

Scriven, Jessica J. January 2016 (has links)
Bumblebees are ecologically and economically important as pollinators, but some species are suffering severe declines and range contractions. In this thesis, three cryptic bumblebee species are studied to elucidate differences in their distribution, ecology and population genetics. As a result of their high morphological similarity, very little is known about the lucorum complex species: B. lucorum, B, cryptarum and B. magnus. In this study, their distributions across Great Britain were assessed using molecular methods, revealing that B. lucorum was the most abundant and most generalist of the three species, whereas B. magnus was the rarest and most specialised, occurring almost exclusively on heathland. Additionally, both B. magnus and B. cryptarum were more likely to be present at sites with cooler summer temperatures. Cryptic species represent interesting models to investigate the levels of niche differentiation required to avoid competitive exclusion. Characterising the niches of these species at a single site across the flight season revealed differences along three niche dimensions: temporal activity, weather sensitivity and forage-resource use. These species exhibited asymmetric niche overlap; a combination of ecological divergence and spatio-temporal heterogeneity may contribute to maintaining them in sympatry. Population genetic studies can be highly informative for understanding species ecology and for conservation management. The differences in habitat specialisation exhibited by these bumblebee species provide the opportunity to test conflicting hypotheses about links between dispersal and ecological specialisation: are habitat specialists selected to have low or high dispersal ability? Based on microsatellite analysis, the generalist B. lucorum had high levels of genetic diversity and little population structure across large spatial scales. The habitat specialist B. magnus had the lowest genetic diversity but similar levels of population differentiation to the moderate generalist, B. cryptarum. However, unlike B. cryptarum, B. magnus population differentiation was not affected by geographic distance, suggesting that this specialist species may maintain effective dispersal across large scales despite being restricted to a fragmented habitat. Bergmann’s rule is a well-known ecogeographic rule describing geographical patterns of body size variation, whereby larger endothermic species are found more commonly at higher latitudes. Ectotherms, including insects, have been suggested to follow converse Bergmann’s gradients, but the facultatively endothermic nature of bumblebees makes it unclear which pattern they should adhere to. This thesis reports caste-specific differences in body size between the three lucorum complex species in agreement with Bergmann’s rule: queens and males of B. cryptarum and B. magnus, which were found more commonly at higher latitudes and at sites with cooler temperatures, were larger than those of B. lucorum. Population genetic studies of invertebrates generally require the destruction of large numbers of individuals, which is often undesirable. Testing a variety of faecal collection and DNA extraction methods demonstrated that it is possible to obtain DNA of sufficient quality for genotyping from bumblebee faeces, without harming the individuals. This method would be valuable for studies of rare or declining bee species, for queens in reintroduction projects, and may be applicable to other arthropods. Overall this thesis contributes substantially to our knowledge of the ecology and population genetics of three important pollinator species. It provides data to inform species conservation, as well as understanding of ecosystem functioning and population dynamics. Furthermore, it successfully uses these cryptic species as a model to test several fundamental ecological theories.
194

Vliv barvy na efektivitu Moerickeho pastí v kontextu rostlinné nabídky a environmentálních faktorů okolí pastí

PERLÍK, Michal January 2017 (has links)
Community composition of floricolous insects, beetles (Coleoptera) and bees and wasps (aculeate Hymenoptera) at six sites in Podyjí National Park was studied using four different colours of Moericke (pan) traps. Effects of different trap colours, forest habitats, and environmental variables in traps vicinity on the number of species and species composition were analysed. Influence of different conditions on trap catch is discussed.
195

Seleção de linhagens e efeito do hospedeiro na qualidade de Trichogramma pretiosum Riley, 1879 (Hymenoptera: Trichogrammatidae) para o controle de Tuta absoluta (Meyrick, 1917) (Lepidoptera: Gelechiidae) em tomateiro / Strain selection and host effect on Trichogramma pretiosum Riley, 1879 (Hymenoptera: Trichogrammatidae) quality for Tuta absoluta (Meyrick, 1917) (Lepidoptera: Gelechiidae) control in tomato crops

Guilherme dos Reis Vasconcelos 17 January 2013 (has links)
O objetivo do presente trabalho foi selecionar a linhagem mais adequada de T. pretiosum para o controle de T. absoluta na cultura do tomate, dentre as linhagens da coleção do Laboratório de Biologia de Insetos do Departamento de Entomologia e Acarologia da Escola Superior de Agricultura \"Luiz de Queiroz\", e comparar a qualidade dos insetos criados em ovos do hospedeiro alternativo, Anagasta kuehniella (Zeller, 1879) com aquela dos insetos oriundos de ovos de T. absoluta, com vistas à utilização do parasitoide para o controle da traça-do-tomateiro. Para atingir tal objetivo foram realizadas as seguintes etapas: seleção de linhagens, efeito da idade do hospedeiro no parasitismo, efeito do hospedeiro na qualidade do parasitoide e número de parasitoides a ser liberado por ovo da praga. A linhagem PR de T. pretiosum, proveniente do Paraná, foi, entre as estudadas, a mais adequada para o uso em programas de controle biológico de T. absoluta. T. pretiosum parasitou igualmente ovos de T. absoluta de 0 a 48 horas de idade. A capacidade de parasitismo, longevidade, capacidade locomotora e o tamanho do parasitoide foram reduzidos quando provenientes de ovos da traça-do-tomateiro em comparação a insetos emergidos de ovos de A. kuehniella. O número ideal de T. pretiosum a ser liberado na cultura do tomate para o controle de T. absoluta foi superior a 50 parasitoides/ovo. Portanto, T. pretiosum pode ser utilizado em programas de Controle Biológico Aplicado, visto que, devido à menor qualidade dos parasitoides provenientes de ovos de T. absoluta, o inimigo natural terá dificuldades em se estabelecer no campo, indicando ser necessário um grande número de liberações, pois T. pretiosum terá uma ação contra T. absoluta semelhante a um inseticida, desde que os parasitoides que nascerem nas gerações subsequentes às liberações serão menos agressivos e competitivos do que os insetos da natureza. / The aim of this study was to select the most suitable T. pretiosum strain for the biological control of T. absoluta in tomato crops, within the existing strains in the Laboratório de Biologia de Insetos\' colection at Escola Superior de Agricultura \"Luiz de Queiroz\", and compare the quality of the insects reared on eggs of the alternative host Anagasta kuehniella (Zeller, 1879) and on eggs of T. absoluta. For this, the following characteristics were studied: strain selection, host age effect on parasitism, different host effect on parasitoid quality and ideal number of released parasitoid per pest egg. The T. pretiosum strain PR, originated in Paraná state, was the most suitable for its use in T. absoluta biological control programs. T. pretiosum parasitism rate was the same for eggs aged from 0 to 48 hours. T. pretiosum\'s parasitism capability, longevity, mobility capability and parasitoid size were reduced when reared on T. absoluta eggs in comparison to the ones reared on A. kuehniella eggs. The ideal parasitoid number for release in order to control T. absoluta in tomato crops is over 50 per egg. Since the quality of parasitoids hatched from T. absoluta eggs is lower, populations of T. pretiosum will present difficulties to establish itself in the field. Therefore, T. pretiosum should be used in applied biological control programs, where a large number of parasitoids is released in the field from time to time, which will act similarly to insecticides.
196

Comportamento olfativo de três espécies de parasitóides (Hymenoptera: Braconidae) de moscas-das-frutas (Diptera: Tephritidae) / Olfactory behavior of three parasitoid species (hymenoptera: braconidae) of fruit flies (diptera: tephritidae)

José Wilson Pereira da Silva 22 July 2005 (has links)
Entre os inimigos naturais das moscas-das-frutas, os representantes da subfamília Opiinae (Hymenoptera: Braconidae) têm sido os mais utilizados em programas de controle biológico. Entretanto, algumas espécies da subfamília Alysiinae são comumente relacionadas ao parasitismo desses dípteros, em particular Asobara anastrephae (Muesebeck). No estudo da eficiência desses parasitóides é de fundamental importância o conhecimento dos estímulos utilizados para a localização do hábitat de seus hospedeiros. Dessa forma, foram avaliadas as respostas olfativas do parasitóide exótico Diachasmimorpha longicaudata Ashmead, e dos nativos, Doryctobracon areolatus (Szépligeti) e A. anastrephae a frutos de goiaba (Psidium guajava L.) com e sem larvas de moscasdas- frutas, em condições de laboratório. D. longicaudata e D. areolatus foram também estudados em telado. As fêmeas de D. longicaudata e de D. areolatus responderam aos odores de frutos podres não-infestados, embora D. areolatus também tenha sido atraído aos frutos em maturação inicial (de vez). As fêmeas dessas espécies demonstraram reconhecer os voláteis de frutos com larvas de Ceratitis capitata (Wied.). No entanto, em bioensaios realizados com frutos contendo larvas de diferentes instares, as fêmeas de D. longicaudata não foram capazes de separar frutos com larvas dos primeiros instares dos de terceiro instar de C. capitata. Nas avaliações dos voláteis liberados dos frutos com larvas de C. capitata e de Anastrepha fraterculus (Wied.), as fêmeas de D. longicaudata orientaram-se aos voláteis dos frutos com ambas as espécies de hospedeiros, mas diferiram significativamente dos voláteis com larvas de C. capitata. As fêmeas de D. areolatus também demonstraram respostas para ambas as espécies, mas diferiram significativamente dos voláteis de frutos com larvas de A. fraterculus. As fêmeas de A. anastrephae orientaram-se de forma similar para os campos com odores de frutos infestados com ambas as espécies de moscas-dasfrutas. Em área coberta (telado), as fêmeas de D. longicaudata orientaram-se pelos voláteis de frutos podres com e sem larvas, porém não diferenciaram significativamente os hospedeiros. As fêmeas de D. areolatus não foram atraídas para os frutos nas gaiolas no solo independentemente do hospedeiro, sugerindo que este parasitóide não forrageia em frutos caídos. / Parasitoids of the Opiinae subfamily (Hymenoptera: Braconidae) are among the most used natural enemies in fruit fly control programs. Furthermore, some species of the subfamily Alysiinae, such as Asobara anastrephae (Muesebeck), are commonly associated to the parasitism of these dipterans. The study of efficiency of parasitoids is essential in order to understand the mechanisms that regulate both prey and habitat searching behavior of natural enemies. In this work we evaluated the behavioral response of the native parasitoid species Doryctobracon areolatus (Szépligeti), A. anastrephae as well as the exotic species Diachasmimorpha longicaudata Ashmead, to guava fruit (Psidium guajava L.) with and without fruit flies larvae under laboratory conditions. In addition, behavioral response of D. longicaudata and D. areolatus were also determined under natural conditions. Parasitoid females of D. longicaudata and D. areolatus responded to volatiles from non-infested fermented fruits, moreover D. areolatus also attracted to fruits on initial maturation. Both species recognized volatiles from fruits infested with Ceratitis capitata (Wied.) larvae; however D. longicaudata females were unable to differentiate volatiles from fruit infested with different larval instars of C. capitata. Olfactometer choice bioassays showed that females of both parasitoid species oriented to volatiles released from fruits infested with C. capitata and Anastrepha fraterculus (Wied.) larvae, however preference differed significantly for volatiles associated with each fruit fly species. Under natural conditions, D. longicaudata was attracted to volatiles released from infested and non-infested fermented fruits. Nevertheless, D. areolatus did not respond to volatiles from infested fruits placed on the ground, suggesting that this species do not prey on fallen fruits.
197

Efeitos de inibidores de proteinases de soja em organismos não-alvo associados à cultura da cana-de-açúcar / Effects of soybean proteases inhibitors on non-target organisms associated to sugarcane

Renata Araújo Simões 17 January 2008 (has links)
Genes de plantas que codificam inibidores de enzimas digestivas de insetos têm sido introduzidos em plantas cultivadas visando o controle de pragas. Os inibidores de proteinases estão presentes nos tecidos vegetais, principalmente nas sementes, e atuam em resposta a ataques por herbívoros e patógenos. Inibidores de serino-proteinases (IPs) dos tipos Bowman-Birk e Kunitz isolados de sementes de soja foram inseridos em variedades de cana-de-açúcar para aumentar a resistência à broca Diatraea saccharalis (Fabr.), principal praga desta cultura. Para utilização de plantas geneticamente modificadas contendo inibidores de proteinases é necessário um conhecimento profundo de sua sustentabilidade e segurança ambiental, determinando a estabilidade da característica inserida e os seus efeitos nos organismos não-alvo. O objetivo desta pesquisa foi avaliar os efeitos diretos e indiretos de inibidores de proteinases de soja em organismos não-alvos: um parasitóide larval, Cotesia flavipes (Cam.) (Hymenoptera: Braconidae); um patógeno, Metarhizium anisopliae (Mestch.) Sorokin (Deuteromycotina: Hyphomycetes); um polinizador, Apis mellifera L. (Hymenoptera: Apidae) e um decompositor, Scheloribates praeincisus (Berlese) (Acari: Oribatida: Scheloribatidae); associados à cultura da cana-de-açúcar. O consumo de Kunitz e BBI não afetou a sobrevivência de S. praeincisus. Por outro lado, a ingestão dos inibidores semi-purificados e purificados do tipo Kunitz diminuiu a duração das fases imaturas de S. praeincisus. A ingestão de folhas de cana GM expressando inibidores de proteinases (Kunitz e BBI) não afetou o tempo de desenvolvimento e a sobrevivência dos imaturos deste oribatídeo quando comparada à ingestão de suas isolinhas. Os inibidores de proteinases semi-purificados e purificados não afetaram a duração dos períodos larval e pupal, o peso e número de pupas e percentual de emergência do parasitóide C. flavipes em D. saccharalis. Por outro lado, a proporção de fêmeas em relação a machos de C. flavipes foi maior no tratamento onde as lagartas foram alimentadas com dieta contendo 0,5% de inibidores semi-purificados comparado-se à testemunha. A proporção fêmea:macho foi significativamente maior também quando os parasitóides foram alimentados com o inibidor do tipo Kunitz em relação ao controle e aos parasitóides alimentados com BBI. A adição de 0,5% (p/v) de inibidores de proteinases semi-purificados e 0,05% (p/v) de inibidores purificados do tipo Kunitz nos meios de cultura MC e BDA resultaram em maiores crescimento vegetativo e produção de conídios de M. anisopliae. Os inibidores purificados do tipo BBI não alteraram a esporulação do fungo. Os resultados dos estudos com A. mellifera não foram conclusivos e novas investigações precisam ser conduzidas para esclarecer os potenciais efeitos de inibidores de proteinases em abelhas. De uma forma geral, observou-se que os inibidores de proteinases (Kunitz e BBI) não afetaram negativamente os organismos não-alvo testados. Por outro lado, a ingestão de inibidor do tipo Kunitz alterou positivamente alguns parâmetros biológicos de C. flavipes, M. anisopliae e S. praeincisus. / Genes of plants expressing insect proteinase inhibitors have been introduced into plants for pest control. Proteases inhibitors are present in plant tissues, mainly in seeds, and act in response to predators and pathogens. The Bowman-Birk type and Kunitz type of serine proteases inhibitors (PI) from soybean seeds are been used to increase resistance of sugarcane to Diatraea saccharalis (Fabr.), the most important pest of this crop. The sustainability and environmental safety of PI crops is still unknown. For these reasons, it is necessary to understand the stability and the non-target effects of this new trait. The objective of this study was to evaluate the direct and indirect effects of soybean PI on the following non-target organisms associated to sugarcane: the larval parasitoid, Cotesia flavipes (Cam.) (Hymenoptera: Braconidae); the entomopathogen, Metarhizium anisopliae (Mestch.) Sorokin (Deuteromycotina: Hyphomycetes); the pollinator Apis mellifera L. (Hymenoptera: Apidae) and the soil mite involved in the process of recycling organic matter, Scheloribates praeincisus (Berlese) (Acari: Oribatida: Scheloribatidae). Kunitz and BBI did not affect S. praeincisus survival. On the other hand, Kunitz semi-purified and purified inhibitor ingestion reduced duration of the immature stages of S. praeincisus. Ingestion of GM senescent leaves did not have an effect on mite immatures development time and survival compared to ingestion of its isolines leaves. The semi-purified and purified proteinases inhibitors did not alter either the duration of larval and pupal stages of C. flavipes on D. saccharalis, or weight and number of pupae and parasitoid emergence. In other hand, the parasitism and proportion of female was higher on the treatment where caterpillars were fed with diet containing 0.5% of semi-purified inhibitors, comparing to control. The ratio female:male was significantly higher also when parasitoids were fed to the Kunitz type inhibitor compared to the control and BBI. The addition of 0.5 % (w/v) of semi- purified proteinase inhibitors and 0.05% (w/v) of Kunitz type purified inhibitors on two culture media (CM and PDA), resulted in increase of vegetative growth and production of conidia. BBI type purified inhibitors did not change the fungus sporulation. The results from the studies with A. mellifera were not conclusive and investigations are needed to clarify the potential impact of proteinase inhibitors on A. mellifera. Overall, proteinase inhibitors (Kunitz and BBI) did not negatively affect the non-target organisms tested. Conversely, ingestion of the Kunitz type of proteinase inhibitors altered positively some biological parameters of C. flavipes, M. anisopliae and S. praeincisus.
198

BUMBLE BEES UTILIZE WEEDY MARGINS AND ARE UNAFFECTED BY THE INCREASING URBAN GRADIENT

Reeher, Paige A. 27 June 2019 (has links)
No description available.
199

The Effects of Urban Land Use on Wasps (Hymenoptera: Apocrita)

Freeman, Klaire E. 10 May 2013 (has links)
No description available.
200

High throughput DNA barcoding to assess the diversity of Laurentian insects

Kalboussi, Malek 08 1900 (has links)
La grande diversité d’insectes et la quantité de spécimens recueillis lors de l’échantillonnage constituent les plus grands défis de la systématique des insectes. Le tri des échantillons au niveau des espèces est nécessaire avant qu’ils puissent être utilisés pour des enquêtes sur les modèles de biodiversité. En raison de l’obstacle taxonomique, le manque d’expertise taxonomique, de nombreuses études sur la diversité des insectes classe les spécimens en Unités Morphologiques Opérationnelles (MorphOTUs), aussi appelées morpho-espèces, en désignant les groupes définis subjectivement en fonction de caractéristiques morphologiques évidentes. Cependant, il est long et douteux de définir avec précision les limites des espèces en se fondant sur les MorphOTUs, surtout dans les groupes où il y a de minuscules insectes et une grande similarité au niveau des espèces, comme chez les Hyménoptères. Le codage à barres de l’ADN, une approche taxonomique discriminatoire qui utilise des séquences d’ADN, a accéléré la classification taxonomique et peut être une approche alternative aux MorphOTUs. Cependant, il est crucial d’utiliser une stratégie fiable et économique de codage à barres ADN pour traiter un grand nombre d’échantillons. En outre, le codage à barres d’ADN devrait fonctionner avec les espèces problématiques dans l’entomologie moléculaire comme on l'observe parfois avec les hyménoptères. Afin de mettre en œuvre une évaluation rapide de la biodiversité des Hyménoptères, optimiser les de étapes de barcodage d`ADN (extraction d’ADN, amplification par PCR et séquençage) était le premier objectif de ce projet de recherche. On a testé et optimisé une extraction d’ADN arrivant à une méthode coûtante 0,20 dollars par spécimen. On a validé la performance adéquate des mini-codes à barres d’ADN, réduits en taille à 313bp, pour établir une classification d’Unités Taxonomiques Opérationnelles Moléculaires (MOTUs) comparable à celle du codage à barres d’ADN couramment utilisé, de longueur de 658bp. On a adopté ce protocole optimisé pour le codage à barres de 517 spécimens d’Hyménoptères échantillonnés par des pièges aspirateurs situés dans la forêt laurentienne de l’Est du Canada. Avec le séquençage multiplexé à haut débit Illumina, impliquant des amplicons étiquetés, on a obtenu des mini-codes à barres pour 88% des spécimens. Le coût et le temps nécessaires pour générer des données MOTU, grâce à notre approche de codage à barres d’ADN, étaient environ la moitié de celui de la classification morphologique en MorphOTUs. Le deuxième objectif de ma recherche était de comparer l’efficacité du tri morphologique des MorphOTUs avec l’identification moléculaire et la délimitation par MOTUs. On a démontré iii une forte congruence entre l’identification morphologique et moléculaire au niveau taxonomique de la famille dansla base de données Barcode of Life (BOLD) et GenBank (93 %), alors que seulement 18 % des mini-codes à barres ont été attribués à des identifications plus précises (genre ou espèce). La délimitation moléculaire s’est faite avec quatre méthodes de regroupement différentes (basée sur la distance : Découverte automatique de l’écart de codes à barres (ABGD) et Assemblage des espèces par partitionnement automatique (ASAP) ; basée sur un dendrogramme : Coalescente mixte généralisée du yule (GMYC) et Processus bayésien de l’arbre de poisson (bPTP)). En générale, les méthodes moléculaires ont plus que doublé la diversité estimée des MorphOTUs des Hyménoptères. Les MOTUs étaient en grande partie incompatibles avec les MorphOTUs (ratio d’appariement <0,35). Les méthodes basées sur la distance ont donné des résultats plus conformes au tri morphologique que les méthodes basées sur les arbres, en particulier dans la superfamille des Chalcidoidea. Compte tenu de la comparaison entre le coût et le temps des méthodes de classification moléculaire et morphologique, nos résultats suggèrent que le codage à barres mini-ADN pour estimer la diversité des espèces d’Hyménoptères est plus économique que le tri par MorphOTU. Cependant, bien que les méthodes MorphOTU et MOTU aient donné de nombres unités taxonomiques différentes, les analyses de la diversité utilisées actuellement tiennent compte de l’abondance et d’autres paramètres. On n’a pas évalué si les MorphOTUs et les protocoles d’entente donneraient des résultats suffisamment équivalents dans la recherche réelle sur les diversités α et β, c’est-à-dire pour évaluer s’ils pouvaient tout de même tous deux être utiles. / The great insect diversity and the quantity of insect specimens collected during sampling constitute the biggest challenges facing insect systematics. Sorting samples to the species level is necessary before they can be used for investigations of biodiversity patterns. Because of the Taxonomic impediment, the lack of taxonomic expertise, many insect diversity studies sort specimens to Morphological Operational Taxonomic Units (MorphOTUs), also known as morphospecies, classifying subjectively defined groups based on obvious morphological features. However, accurately defining species boundaries based on MorphOTUs is time consuming and questionable, especially in groups with tiny insects and great species-level similarity such as Hymenoptera. DNA barcoding, a taxonomic discriminatory approach that employs DNA sequences, has accelerated taxonomic classification and may be an alternative approach to MorphOTUs. However, it is crucial to use a reliable and economic DNA barcoding strategy to deal with a large number of samples. Additionally, DNA barcoding should work with species problematic in molecular entomology as is sometimes observed with Hymenoptera. In order to implement a rapid biodiversity assessment of Hymenoptera, optimizing the DNA barcoding steps (DNA extraction, PCR amplification, and DNA sequencing) was the first objective of this present research. We tested and optimized a DNA extraction arriving at a method costing 0.20CAD per specimen. We validated the adequate performance of 313bp mini barcodes for establishing Molecular Operational Taxonomic Units (MOTUs) classification, comparable to that of the commonly used full-length DNA barcode of 658bp. We adopted this optimized protocol to barcode 517 Hymenoptera specimens sampled with suction traps located in the Laurentian Forest of eastern Canada. With multiplexed Illumina high throughput sequencing of tagged amplicons, we obtained mini-barcodes for 88% of specimens. The cost and time taken to generate MOTU data through our DNA barcoding approach was approximately twice that of morphological identification for MorphOTU designation. The second objective of my research was to compare the efficacy of morphological sorting of MorphOTUs with the molecular identification and delimitation of MOTUs. We found a high taxonomic congruence between morphological and molecular identification at family level in Barcode of Life (BOLD) and GenBank databases (93%), whereas only 18% of mini-barcode data was assigned to more precise identification (genus or species). Molecular delimitation based on four different clustering methods (distance-based: Automatic Barcode Gap Discovery v (ABGD) and Assemble Species by Automatic Partitioning (ASAP); tree-based: Generalized Mixed Yule Coalescent (GMYC) and Bayesian Poisson Tree Processes (bPTP)) resulted in more than doubling the estimated diversity of Hymenoptera as compared to MorphOTUs. The MOTUs were largely incongruent with MorphOTUs (match ratio <0.35). Distance-based methods gave results more congruent with morphological sorting than tree-based methods, especially within the Chalcidoidea superfamily. Taking into account the comparison between the cost and time of molecular and morphological classification methods, our results suggest that mini-DNA barcoding to estimate a proxy for Hymenoptera species diversity is more economical than MorphOTU sorting. However, although MorphOTU and MOTU methods gave different numbers of species, actual diversity analyses take into account abundance and other parameters. We did not evaluate whether MorphOTUs and MOTUs would yield sufficiently equivalent results in actual α- and β diversity research: that is, they may yet both be fit for purpose

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