Dissertations / Theses on the topic 'Megachile'

L'abeille solitaire coupeuse de feuilles megachile rotundata possede une biologie favorisant son elevage et son utilisation en tant que pollinisateur des cultures de plantes fourrageres. Ses cires epicuticulaires sont constituees de 35 pour cent d'acides gras, 26 pour cent d'alcanes et 39 pour cent de monoenes. Ces derniers permettent de distinguer d'une part les males des jeunes femelles vierges qui possedent proportionnellement plus de pentacosene-7 et de pentacosene-9, d'autre part de separer de ces deux groupes les femelles agees chez qui la chute des quantites de monoenes-7 est compensee par de plus fortes proportions de monoenes-5. Les glandes labiales cephaliques des males produisent essentiellement un compose non determine, peut-etre un hexanoate d'alcool a chaine ramifiee. La secretion de la glande de dufour est caracterisee par une serie homologue d'esters d'octyle, leur production diminue chez les femelles nidifiantes. Le contenu des glandes labiales thoraciques est constitue des memes acides gras que ceux trouves sur la cuticule. Les quantites d'acide linoleique augmentent chez les femelles nidifiantes. Les jeunes femelles et leur extrait pentanique provoquent un accroissement de l'activite des males: ils explorent alors les taches sombres et bondissent sur la femelle si elle est decouverte. Seule la fraction, de cet extrait, contenant les monoenes retablit ces comportements chez les males

Dramatic changes in ambient temperature can have a significant impact on insect physiology throughout development. The accumulations of the deleterious physiological effects throughout low temperature exposure are collectively known as chill injury. The mechanisms underpinning the downstream physiological consequences of chill injury such as oxidative stress, perturbations in ion homeostasis, and changes in metabolism have yet to be elucidated. Brief, daily pulses of increased temperatures have been shown to repair and/or protect against the continued accumulation of chill injury, leading to an increase in survival across several insect taxa. Until recently, no transcriptomic-level assessments of gene expression during low temperature stress had been conducted. In this document I present a comparison of low-temperature stress response mechanisms across life stages in the alfalfa leafcutting bee, Megachile rotundata. RNA-seq, qPCR and oxidative stress assays were used to determine the physiological effects of low temperature exposure on two life stages: one adapted for low-temperature exposure and one that is not. Differential expression analysis revealed distinct gene expression profiles between life stages. The lack of overlap in expression profiles suggests different mechanisms are driving the response. Furthermore, an overlap in the functional classes of differentially expressed transcripts suggest that the response may be physiologically robust, even though the response is variable at the level of gene expression. Gene expression suggests oxidative stress may be a critical component in chill injury response and recovery. Antioxidant activity and lipid peroxidation, a common proxy for oxidative stress, were assessed in both life stages. M. rotundata’s ability to cope with an induced oxidative stress did not vary between treatments in either life stage. Furthermore, a lack of statistical differences between treatments in lipid peroxidative do not support the hypothesis that the benefits of fluctuating temperatures are, in part, due to reduction in oxidative stress.
NDSU GraSUS Fellowship
USDA-ARS
North Dakota State University. Department of Biological Sciences
Sheila Kath Scholarship

Spring conditions stimulate development of many plants and animals after a period of winter dormancy. Climate change is predicted to cause earlier spring thaws, increasing temperature variability, and more frequent cold snaps. These conditions cause two problems for organisms. First, environmental cues may mislead organisms developing under these scenarios if temperature and photoperiod cues give conflicting information. Second, organisms outside of their overwintering stages can be less tolerant of cold exposure and may be at risk of injury or death. Little is known about the consequences of these conditions on bee species. Therefore, I examined these scenarios in a solitary bee species, Megachile rotundata. I hypothesized they would be sensitive to temperature changes to regulate spring emergence because of their cavity nesting life history where photoperiod cues likely buffered. I found light is buffered by the brood cell by approximately 80% and emergence can be synchronized by photoperiod. Furthermore, I demonstrated that M. rotundata may be more sensitive to temperature cues compared to photoperiod cues in regulating emergence. To understand how spring cold snaps during development affect adult bees, I comprehensively assayed M. rotundata cold tolerance. I discovered that cold exposure during development resulted in numerous sub-lethal effects in adult bees such as a decrease in flight performance and longevity. Furthermore, developmental cold stress affected adult thermal performance, such as chill coma recovery. Cold tolerance varies across development and the post-diapause quiescent stage was more tolerant to cold than pupal or emergence ready stages. Temperature fluctuations of spring may affect the timing of emergence but also the health of adult bees if they experienced a cold snap during development.
Doctoral Dissertation Fellowship

Megachile rotundata is an agriculturally important pollinator of alfalfa and is not doing well in the U.S due to a 50% return rate (Pitts-Singer and Bosch, 2011). Nesting boxes can reach temperatures between 35˚C-48˚C (see Chapter 2). These temperatures can cause damage to multiple stages of development, including death (Barthel et al. 2002, Rossie et al. 2010). To date, it is unclear how cavity temperature varies across the box. Traditionally, nesting cavity temperatures have been monitored using 1-3 temperature probes to measure thousands of cavities (CaraDonna et al. 2018). These methods do not account for the accuracy of the temperature probe to depict temperatures several cm away from the probe. To asses this variation I have designed a 3D printed nesting box that holds one temperature probe for every four cavities. I found that cavity temperature impacts nesting preference, and survival, of the alfalfa leafcutting bee.
United States. Department of Agriculture
North Dakota State University. Department of Biological Sciences
North Dakota State University. College of Science and Mathematics
NSF IOS 1557940
NSF EPSCoR 1826834

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES
Terrestrial ecosystems, solitary bees and wasps play important roles as pollinators, predators and parasites. Most part of the life of these Hymenoptera is designed to aspects related to nesting, including the search of the nest site, nest construction and food collection to rear the larvae. However, in natural environments the nests of these insects are difficult to find. A solution to this problem, at least for some species, is the use of artificial burrows in the field (trap nests). Using trap nests it is possible to collect standardized samples and to study the biology of some species. Thus, the community of solitary bees and wasps, nesting in trap nests was evaluated using parameters such as richness, diversity and nest abundance in two different agroecosystems of the state of Pernambuco, northeastern Brazil: sugarcane monoculture and polyculture. Moreover, the natural history and nesting biology of a bee species (Megachile dentipes) collected in the trap nests was studied. In this study, the main aspects of life history (seasonality, diameter of the nests, sex ratio, parasitism, development time) and nesting biology (nest architecture, nesting behavior, larval diet) was studied. Insects were sampled using the technique of trap nests, which consisted of 1) cardboard tubes inserted into blocks of wood of different diameters (4, 6, 8 and 10 mm), and 2) wooden planks, drilled lengthwise (5, 6, 8, 10 and 12 mm in diameter) and covered with a transparent plastic sheet (observation-nests). In each agroecosystem 3.360 cardboard tubes were available for nesting during one year (June/2009 to May/2010) and 1000 holes of observationnests during five months (October/2009 to February/2010). In the monoculture a total of 259 nests, 86 (33.2%) build by bees and 173 (66.8%) by wasps were sampled. Five species of bees were sampled, and Megachile dentipes was the most abundant bee species in the sugarcane (n = 76; 85%). In the polyculture area, 411 nests were collected, being 254 (61.8%) of bees and 157 (38.2%) of wasps. In this environment, 14 spp. nesting bee species were recorded. The leaf-cutter bee Megachile dentipes was also the most abundant (n = 117 nests, 46%). The abundance of bee nests, species richness and diversity of bees and wasps was significantly higher in the polyculture area compared to monoculture area. It is suggested that plant richness is a determining factor in the occurrence of the species. However, other factors such as distance from forest fragments and the use of herbicides and burning, might have influence in the low richness and diversity of bees and wasps in the area with sugarcane monoculture. Regarding Megachile dentipes it was shown that it is an polilectic species, collecting pollen from a wide spectrum pollen from mainly five botanical families: Asteraceae, Rubiaceae, Euphorbiaceae, Mimosaceae and Scrophulariaceae. This species showed a clear preference for nesting in the dry periods of the year in both studied areas, with peaks in October and December. Furthermore, this species had several generations throughout the year (multivoltine). It was demonstrated experimentally that recognition of the cavities by females is determined by the nest position in the blocks. Probably, chemical signals (marking the cavity) are not used, at least in the initial recognition of the nests. Nest structure of M. dentipes differs from most species because the lining of the brood cell is made from chewed leaves unlike the other species that involve the brood cells with whole leaves not chewed.. Biological and ecological characteristics of M. dentipes, as e.g. abundance and poliletia, makes this species a good candidate for management programs aimed at pollination, but further studies are necessary for that purpose.
Nos ecossistemas terrestres, abelhas e vespas solitárias desempenham essenciais papéis como polinizadores, predadores e parasitas. Grande parte da vida das fêmeas desses himenopteros é destinada à nidificação, como busca pelo local do ninho, construção do ninho e coleta do alimento larval. Contudo, os ninhos desses insetos em ambientes naturais são difíceis de serem encontrados. Uma solução para este problema, pelo menos para algumas espécies, é a utilização de cavidades artificiais no campo (ninhosarmadilha), uma vez que amostragens dos ninhos podem ser realizadas de forma padronizada em diferentes ambientes, além de fornecerem dados acerca da biologia das espécies capturadas. Diante disso, a comunidade de abelhas e vespas solitárias nidificantes em ninhos armadilha foi avaliada a partir de parâmetros como riqueza, diversidade e abundância de ninhos em dois agroecossistemas em Pernambuco: monocultura canavieira e sistema de policultura. Além disso, foi estudada a história natural e biologia de nidificação da espécie de abelha (Megachile dentipes) mais abundante nos ninhos-armadilha. Neste estudo foram avaliados os principais aspectos relacionados à história de vida (sazonalidade, razão sexual, parasitismo, tempo de desenvolvimento) e biologia de nidificação (arquitetura do ninho, comportamento de nidificação, dieta larval) de M. dentipes. Os insetos foram amostrados através da técnica de ninhos-armadilha, que consistiu de 1) tubos de cartolina inseridos em blocos de madeira de diferentes diâmetros (4, 6, 8 e 10 mm), e 2) pranchas de madeira, perfuradas longitudinalmente (5, 6, 8, 10 e 12 mm de diâmetro), cobertas com uma lâmina plástica transparente (ninhos-observação). Em cada agroecossistema estudado, foram disponibilizados para nidificação 3.360 tubos de cartolina ao longo de um ano (junho/2009 a maio/2010), e 1.000 cavidades de ninhos-observação durante cinco meses (outubro/2009 a fevereiro/2010). Um total de 259 ninhos, sendo 86 (33,2%) de abelhas e 173 (66,8%) de vespas foi coletado nas armadilhas instaladas na monocultura. Foram amostradas 5 espécies de abelhas, dentre elas, Megachile dentipes, a espécie de abelha mais abundante no canavial (n=76; 85%). Na área com policultura, foram coletados 411 ninhos, sendo 254 (61,8%) de abelhas e 157 (38,2%) de vespas. Neste ambiente, foram registradas 14 spp. de abelhas nidificantes ninhos armadilha. Mais uma vez, a espécie de abelha corta folha Megachile dentipes foi a mais abundante em número de ninhos (n=117; 46%). A abundância de ninhos de abelhas e a riqueza e diversidade de espécies de abelhas e vespas nidificantes em ninhos-armadilha foi significativamente maior em área de policultura quando comparada à monocultura canavieira. É sugerido que a riqueza florística de cada área seja um fator determinante na ocorrência das espécies. Contudo, fatores como a distância de fragmentos de mata e a utilização de herbicidas e queimadas, podem ter colaborado para uma baixa riqueza e diversidade de abelhas e vespas na área com monocultura canavieira. Quanto à espécie Megachile dentipes, observou-se que trata-se de uma espécie polilética, que coleta pólen de um amplo espectro polínico envolvendo, principalmente, cinco famílias botânicas: Asteraceae, Rubiaceae, Euphorbiaceae, Mimosaceae e Scrophulariaceae. Esta espécie mostrou uma clara preferência em fundar ninhos nos períodos mais secos do ano, em ambas as áreas estudadas, com picos de nidificação em outubro e dezembro. Além disso, apresentou várias gerações ao longo do ano (multivoltina). Foi demonstrado experimentalmente que o reconhecimento das cavidades pelas fêmeas baseia-se na posição em que o orifício se encontra no bloco de ninhos-armadilha. Provavelmente, não estão envolvidos sinais químicos (marcação da cavidade) ao menos no reconhecimento inicial dos ninhos. A estrutura do ninho de M. dentipes difere da maioria das espécies descritas até o momento, pois o revestimento da célula de cria é feito com folhas trituradas (manipuladas), diferentemente das demais espécies que envolvem as células de cria com folhas inteiras não trituradas. Características biológicas e ecológicas de M. dentipes, como e.g. abundância e polilectia, tornam esta espécie uma boa candidata a programas de manejo visando a polinização, embora sejam necessários mais estudos direcionados a essa finalidade.

Over the last several decades, the use of solitary bees as an alternative to honey bees (Apis mellifera L.) for pollination of commercial crops has increased, in part as a response to ongoing problems faced by commercial honey bee populations. Two solitary bee species have exhibited great commercial potential: the blue orchard bee, Osmia lignaria Say, and the alfalfa leafcutting bee, Megachile rotundata Fabricius (Hymenoptera: Megachilidae). However, growth of O. lignaria and M. rotundata populations is limited in commercial systems, mainly due to low establishment of females at provided nesting sites, possibly due to mortality, dispersal, or other causes. Rough handling of pre-emergent bees may possibly contribute to post-emergence dispersal in O. lignaria. The current work addressed this hypothesis by using shaking as a proxy for rough handling. However, shaken bees did not establish fewer nests than unshaken bees. Therefore, commercial fruit growers using O. lignaria as pollinators should be able to remove cocoons from their nests as part of their management plan, without fear of increasing bee dispersal. When searching for a nest site, M. rotundata females are known to be attracted to previously used nest materials. The current work verified the attraction of M. rotundata females to old conspecific nests. It also sought to determine which nest components were most attractive to females. It was found that all components were equally attractive. It may be useful to establish these species' learning abilities in a laboratory setting. The current work attempted to design a conditioning protocol for solitary bees. Initially, a method utilizing the proboscis extension reflex was sought. However, O. lignaria and M. rotundata did not reflexively extend their proboscises upon antennal stimulation with sucrose solution. Therefore, another method of conditioning was implemented. Bees were conditioned to respond to floral odors in a feeding bioassay. Results are compared for both species, as well as for males and females. The research completed for this dissertation may provide helpful information for commercial managers of solitary bees seeking to decrease both bee dispersal and the incidence of disease and parasites.

The European honey bee (Apis mellifera) has been present in Australia for approximately 150 years. For the majority of that time it was assumed this species could only be of benefit to Australia‘s natural ecosystems. More recently however, researchers and conservationists have questioned this assumption. Honey bees are an introduced species and may be affecting native fauna and flora. In particular, native bees have been highlighted as an animal that may be experiencing competition from honey bees as they are of similar sizes and both species require nectar and pollen for their progeny. Most research to date has focused on indirect measures of competition between honey bees and native bees (resource overlap, visitation rates and resource harvesting). The first chapter of this thesis reviews previous research explaining that many experiments lack significant replication and indirect measures of competition cannot evaluate the impact of honey bees on native bee fecundity or survival. Chapters two and four present descriptions of nesting biology of the two native bee species studied (Hylaeus alcyoneus and an undescribed Megachile sp.). Data collected focused on native bee fecundity and included nesting season, progeny mass, number of progeny per nest, sex ratio and parasitoids. This information provided a picture of the nesting biology of these two species and assisted in determining the design of an appropriate experiment. Chapters three and five present the results of two experiments investigating the impact of honey bees on these two species of native bees in the Northern Beekeepers Nature Reserve in Western Australia. Both experiments focused on the fecundity of these native bee species in response to honey bees and also had more replication than any other previous experiment in Australia of similar design. The first experiment (Chapter three), over two seasons, investigated the impact of commercial honey bees on Hylaeus alcyoneus, a native solitary bee. The experiment was monitored every 3-4 weeks (measurement interval). However, beekeepers did not agist hives on sites simultaneously so measurement intervals were initially treated separately using ANOVA. Results showed no impact of honey bees at any measurement interval and in some cases, poor power. Data from both seasons was combined in a Wilcoxon‘s sign test and showed that honey bees had a negative impact on the number of nests completed by H. alcyoneus. The second experiment (Chapter 5) investigated the impact of feral honey bees on an undescribed Megachile species. Hive honey bees were used to simulate feral levels of honey bees in a BACI (Before/After, Control/Impact) design experiment. There was no impact detected on any fecundity variables. The sensitivity of the experiment was calculated and in three fecundity variables (male and female progeny mass and the number of progeny per nest) the experiment was sensitive enough to detect 15-30% difference between control and impact sites. The final chapter (Chapter six) makes a number of research and management recommendations in light of the research findings.

Morphologie des antennes etudiees au meb: la souche canadienne possede une plus grande densite de sensilles placoides que la souche francaise, et ce chez les femelles. Observations ecoethologiques: plus grande precocite de la reprise d'activite matinale des femelles canadiennes; le garnissage des cellules d'elevage s'effectue grace a des voyages d'approvisionnement plus frequents pour la souche canadienne; plus grande richesse en pollen de luzerne des nids de souche canadienne. Attraction des megachiles pour la luzerne modifiable par conditionnement alimentaires des larves. Distinction des 2 souches par electrophorese enzymatique grace aux variations des esterases et de la lactate deshydrogenase. Etude du determinisme genetique des esterases

Thirteen New World populations of Megachile rotundata and M. apicalis and two Old World populations of M. rotundata were analyzed at 23 enzyme loci using cellulose acetate electrophoresis. Conventional and G- or C-banded karyotypes were also examined in these populations. The principal findings are (1) No differences were found in the level of heterozygosity between haplodiploid Megachile and that of other diploid insects. This is the first record showing the mean heterozygosity in the hymenopteran genus to be consistent with the mean of most other diploid insects. (2) There was no difference in the level of heterozygosity nor the percent polymorphic loci between males and females, and heterozygotes was discovered in males of the two megachilid species studied. (3) The heterozygosity levels among New World populations of M. rotundata and M. apicalis were similar, but both were more than twice that of Old World rotundata analyzed. This is consistent with the expectations of the founder-event models of both Carson and Templeton. (4) FST, the amount of genetic differentiation among populations, was greater among New World populations of apicalis sampled than among those of rotundata. The extensive commercialization in rotundata may have tempered interpopulation differences which might had occurred had the species been undisturbed. (5) Wrights "isolation by distance" model is inapplicable to either of the two Megachile species. In rotundata, the high gene flow level suggests that human commercial action may effectively disrupt any opportunity for the development of locally adapted populations through selection. In apicalis, little gene flow is present among the populations which is expected by both Carson and Templeton models. The absence of any clinal pattern in apicalis probably better reflects Templeton's transilience model. We believe that the random alteration of major alleles, implicit in transilience, more readily accounts for the distinct local populations we found in apicalis. (6) Chromosomal data suggest that both pericentric inversions and deletions have been involved in karyotype evolution of the two species and a primitive karyotype is proposed based on its ubiquitousness in all populations of both species.
Graduation date: 1993

Insect microbiota plays an essential role on the hosts’ health and fitness, regulating their development, nutrition and immunity. The natural microbiota of bees, in particular, has been given much attention, largely because of the globally reported bee population declines. However, although the worker honey bee has been associated with distinctive and specialized microbiota, the microbiota of solitary bees has not been examined in detail, despite their enormous ecological importance. The main objectives of the present thesis were a) the bacterial community description for various solitary bee species, b) the association of the solitary bee microbiota with ecological factors such as landscape type, c) the relation of the bee foraging preferences with their nest bacterial microbiota, d) the examination of the nest building material contribution to the nest microbiota, e) the isolation of bacterial strains with beneficial or harmful properties for the solitary bee larvae and f) the pathological investigation of bacteria found in deceased solitary bee larvae. The findings of the present study revealed a high bacterial biodiversity in the solitary bee nests. At the same time, the bacterial communities were different for each bee host species. Furthermore, it was shown that the pollen bacterial communities underwent compositional shifts reflecting a reduction in floral bacteria with progressing larval development, while a clear landscape effect was absent. The examination of the nest pollen provisions showed different foraging preferences for each included bee species. Both the pollen composition and the host species identity had a strong effect on the pollen bacteria, indicating that the pollen bacterial communities are the result of a combinatory process. The introduced environmental material also contributed to the nest natural microbiome. However, although the larval microbiota was significantly influenced by the pollen microbiota, it was not much associated with that of the nest material. Two Paenibacillus strains isolated from O. bicornis nests showed strong antifungal activities, while several isolated strains were able to metabolize various oligosaccharides which are common in pollen and nectar. Screening for potential pathogenic bacteria in the nests of O. bicornis unveiled bacterial taxa, which dominated the bacterial community in deceased larvae, while at the same time they were undetectable in the healthy individuals. vi Finally, larvae which were raised in vitro developed distinct bacterial microbiomes according to their diet, while their life span was affected. The present thesis described aspects of the microbiota dynamics in the nests of seven megachilid solitary bee nests, by suggesting which transmission pathways shape the established bacterial communities and how these are altered with larval development. Furthermore, specific bacterial taxa were associated with possible services they might provide to the larvae, while others were related with possible harmful effects. Future studies should integrate microbiota examination of different bee generations and parallel investigation of the microbiota of the nests and their surrounding environment (plant community, soil) to elucidate the bacterial transmission paths which establish the nest microbiota of solitary bees. Functional assays will also allow future studies to characterize specific nest bacteria as beneficial or harmful and describe how they assist the development of healthy bees and the fitness of bee populations
Insektenmikrobiota spielt eine entscheidende Rolle für die Gesundheit und Fitness ihres Wirtes, indem sie dessen Entwicklung, Nahrung und Immunität reguliert. Dem natürlichen Mikrobiom der Honigbiene ist bereits viel Aufmerksamkeit gewidmet worden, was vor allem auf die Berichte des globalen Rückgangs der Bienenpopulationen zurückzuführen ist. Insbesondere sind die Arbeiterinnen der Honigbiene in Verbindung mit unverkennbaren und spezialisierten Bakterien gebracht worden, die hauptsächlich durch soziale Kontakte übertragen werden. Demgegenüber wurden die Mikrobiome der Solitärbienen, trotz ihrer enormen ökologischen Bedeutung, bisher noch nicht im Detail untersucht. Die Hauptziele der vorliegenden Doktorarbeit waren a) die Beschreibung der Bakteriengemeinschaften von unterschiedlichen Solitärbienenarten, b) die Assoziation von Mikrobiota der Solitärbienen mit ökologischen Faktoren wie dem Landschaftstyp, c) die Erforschung der Präferenzen der Nahrungssuche von Solitärbienen in Bezug auf die bakteriellen Gemeinschaften ihrer Nester, d) die Untersuchung des Beitrages des Nestbaumaterials zur gesamten Mikrobiota des Nestes, e) die Isolierung von Bakterienstämmen mit vorteilhaften oder schädlichen Eigenschaften auf die Entwicklung der Solitärbienenlarven und f) die Untersuchung von pathologischen Bakterien, die in verstorbenen Solitärbienenlarven gefunden wurden. Die Ergebnisse der vorliegenden Studie zeigten eine hohe bakterielle Biodiversität in den Nestern der Solitärbienen. Gleichzeitig waren die bakteriellen Gemeinschaften bei jeder Wirtsbienenart unterschiedlich. Es wurde weiterhin gezeigt, dass die Bakteriengemeinschaften der Pollen, Verschiebungen in der Zusammensetzung unterlagen. Diese Verschiebung spiegelt eine Abnahme von Blütenbakterien mit fortschreitender Larvenentwicklung wider. Dabei wurde kein Landschaftseffekt festgestellt. Die Untersuchung des Pollenvorräte der Nester ergab unterschiedliche Präferenzen der Futtersuche für jede einbezogene Bienenspezies. Sowohl die Zusammensetzung des Pollens als auch die Identität der Wirtsspezies wirkten sich stark auf die Pollenbakterien aus, was darauf hindeutet, dass die Pollenbakteriengemeinschaften das Ergebnis eines kombinatorischen Prozesses sind. Das eingetragene Umweltmaterial trug auch zum natürlichen Mikrobiom des Nestes bei. Die Mikrobiota der Larven wurden zudem signifikant durch die Pollenmikrobiota beeinflusst, jedoch nicht sehr stark durch das Nestmaterial. Zwei Paenibacillus-Stämme, die aus Nestern von O. bicornis isoliert wurden, zeigten starke antimykotische Aktivitäten. Darüber hinaus konnten mehrere isolierte Stämme verschiedene Oligosaccharide metabolisieren, die in Pollen und Nektar üblich sind. Das Screening auf potenziell pathogene Bakterien in den Nestern von O. bicornis enthüllte bakterielle Taxa, welche die Bakteriengemeinschaft in verstorbenen Larven dominierten und nicht in den gesunden Individuen nachweisbar waren. Letztendlich entwickelten Larven, die in vitro gezüchtet wurden, ihrer Ernährung entsprechend, unterschiedliche bakterielle Mikrobiome. Außerdem wurde dadurch ihre Lebensdauer beeinträchtigt. In der vorliegenden Arbeit wurden Aspekte der Mikrobiota-Dynamik in den Nestern von sieben Solitärbienen der Familie Megachilidae beschrieben, indem suggeriert wurde, welche Übertragungswege die etablierten Bakteriengemeinschaften prägen und wie diese mit der Entwicklung der Larven verändert werden. Darüber hinaus wurden bakterielle Taxa identifiziert, die für die Wirte mit einem möglichen funktionellen Nutzen verbunden sind, während andere mit möglichen schädlichen Wirkungen in Verbindung stehen. Zukünftige Studien sollten sowohl Mikrobiota-Untersuchungen verschiedener Bienengenerationen als auch die parallele Untersuchung der Mikrobiota der Nester und ihrer Umgebung (Pflanzengemeinschaft, Boden) einschließen, um die bakteriellen Übertragungswege umfassend aufzuklären, die die Nestmikrobiome von Soltärbienen begründen. Außerdem könnten funktionelle Assays in zukünftigen Untersuchungen dazu dienen, spezifische Nestbakterien als nützlich oder schädlich zu charakterisieren, und beschreiben, wie sie die Entwicklung gesunder Bienen und die Fitness der Bienenpopulationen unterstützen