Academic literature on the topic 'Aphid bacteria symbiosis'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the lists of relevant articles, books, theses, conference reports, and other scholarly sources on the topic 'Aphid bacteria symbiosis.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Journal articles on the topic "Aphid bacteria symbiosis"
1
Weldon, S. R., M. R. Strand, and K. M. Oliver. "Phage loss and the breakdown of a defensive symbiosis in aphids." Proceedings of the Royal Society B: Biological Sciences 280, no. 1751 (January 22, 2013): 20122103. http://dx.doi.org/10.1098/rspb.2012.2103.
Full textAbstract:
Terrestrial arthropods are often infected with heritable bacterial symbionts, which may themselves be infected by bacteriophages. However, what role, if any, bacteriophages play in the regulation and maintenance of insect–bacteria symbioses is largely unknown. Infection of the aphid Acyrthosiphon pisum by the bacterial symbiont Hamiltonella defensa confers protection against parasitoid wasps, but only when H. defensa is itself infected by the phage A. pisum secondary endosymbiont (APSE). Here, we use a controlled genetic background and correlation-based assays to show that loss of APSE is associated with up to sevenfold increases in the intra-aphid abundance of H. defensa . APSE loss is also associated with severe deleterious effects on aphid fitness: aphids infected with H. defensa lacking APSE have a significantly delayed onset of reproduction, lower weight at adulthood and half as many total offspring as aphids infected with phage-harbouring H. defensa , indicating that phage loss can rapidly lead to the breakdown of the defensive symbiosis. Our results overall indicate that bacteriophages play critical roles in both aphid defence and the maintenance of heritable symbiosis.
2
Xu, Shifen, Liyun Jiang, Gexia Qiao, and Jing Chen. "The Bacterial Flora Associated with the Polyphagous Aphid Aphis gossypii Glover (Hemiptera: Aphididae) Is Strongly Affected by Host Plants." Microbial Ecology 79, no. 4 (December 4, 2019): 971–84. http://dx.doi.org/10.1007/s00248-019-01435-2.
Full textAbstract:
AbstractAphids live in symbiosis with a variety of bacteria, including the obligate symbiont Buchnera aphidicola and diverse facultative symbionts. The symbiotic associations for one aphid species, especially for polyphagous species, often differ across populations. In the present study, by using high-throughput 16S rRNA sequencing, we surveyed in detail the microbiota in natural populations of the cotton aphid Aphis gossypii in China and assessed differences in bacterial diversity with respect to host plant and geography. The microbial community of A. gossypii was dominated by a few heritable symbionts. Arsenophonus was the most dominant secondary symbiont, and Spiroplasma was detected for the first time. Statistical tests and ordination analyses showed that host plants rather than geography seemed to have shaped the associated symbiont composition. Special symbiont communities inhabited the Cucurbitaceae-feeding populations, which supported the ecological specialization of A. gossypii on cucurbits from the viewpoint of symbiotic bacteria. Correlation analysis suggested antagonistic interactions between Buchnera and coexisting secondary symbionts and more complicated interactions between different secondary symbionts. Our findings lend further support to an important role of the host plant in structuring symbiont communities of polyphagous aphids and will improve our understanding of the interactions among phytophagous insects, symbionts, and environments.
3
Gómez-Valero, Laura, Mario Soriano-Navarro, Vicente Pérez-Brocal, Abdelaziz Heddi, Andrés Moya, José Manuel García-Verdugo, and Amparo Latorre. "Coexistence of Wolbachia with Buchnera aphidicola and a Secondary Symbiont in the Aphid Cinara cedri." Journal of Bacteriology 186, no. 19 (October 1, 2004): 6626–33. http://dx.doi.org/10.1128/jb.186.19.6626-6633.2004.
Full textAbstract:
ABSTRACT Intracellular symbiosis is very common in the insect world. For the aphid Cinara cedri, we have identified by electron microscopy three symbiotic bacteria that can be characterized by their different sizes, morphologies, and electrodensities. PCR amplification and sequencing of the 16S ribosomal DNA (rDNA) genes showed that, in addition to harboring Buchnera aphidicola, the primary endosymbiont of aphids, C. cedri harbors a secondary symbiont (S symbiont) that was previously found to be associated with aphids (PASS, or R type) and an α-proteobacterium that belongs to the Wolbachia genus. Using in situ hybridization with specific bacterial probes designed for symbiont 16S rDNA sequences, we have shown that Wolbachia was represented by only a few minute bacteria surrounding the S symbionts. Moreover, the observed B. aphidicola and the S symbionts had similar sizes and were housed in separate specific bacterial cells, the bacteriocytes. Interestingly, in contrast to the case for all aphids examined thus far, the S symbionts were shown to occupy a similarly sized or even larger bacteriocyte space than B. aphidicola. These findings, along with the facts that C. cedri harbors the B. aphidicola strain with the smallest bacterial genome and that the S symbionts infect all Cinara spp. analyzed so far, suggest the possibility of bacterial replacement in these species.
4
Akman Gündüz, E., and A. E. Douglas. "Symbiotic bacteria enable insect to use a nutritionally inadequate diet." Proceedings of the Royal Society B: Biological Sciences 276, no. 1658 (December 2, 2008): 987–91. http://dx.doi.org/10.1098/rspb.2008.1476.
Full textAbstract:
Animals generally require a dietary supply of various nutrients (vitamins, essential amino acids, etc.) because their biosynthetic capabilities are limited. The capacity of aphids to use plant phloem sap, with low essential amino acid content, has been attributed to their symbiotic bacteria, Buchnera aphidicola , which can synthesize these nutrients; but this has not been demonstrated empirically. We demonstrate here that phloem sap obtained from the severed stylets of pea aphids Acyrthosiphon pisum feeding on Vicia faba plants generally provided inadequate amounts of at least one essential amino acid to support aphid growth. Complementary analyses using aphids reared on chemically defined diets with each amino acid individually omitted revealed that the capacity of the symbiotic bacterium B. aphidicola to synthesize essential amino acids exceeded the dietary deficit of all phloem amino acids except methionine. It is proposed that this shortfall of methionine was met by aphid usage of the non-protein amino acid 5-methylmethionine in the phloem sap. This study provides the first quantitative demonstration that bacterial symbiosis can meet the nutritional demand of plant-reared aphids. It shows how symbiosis with micro-organisms has enabled this group of animals to escape from the constraint of requiring a balanced dietary supply of amino acids.
5
Shigenobu, Shuji, and David L. Stern. "Aphids evolved novel secreted proteins for symbiosis with bacterial endosymbiont." Proceedings of the Royal Society B: Biological Sciences 280, no. 1750 (January 7, 2013): 20121952. http://dx.doi.org/10.1098/rspb.2012.1952.
Full textAbstract:
Aphids evolved novel cells, called bacteriocytes, that differentiate specifically to harbour the obligatory mutualistic endosymbiotic bacteria Buchnera aphidicola . The genome of the host aphid Acyrthosiphon pisum contains many orphan genes that display no similarity with genes found in other sequenced organisms, prompting us to hypothesize that some of these orphan genes are related to lineage-specific traits, such as symbiosis. We conducted deep sequencing of bacteriocytes mRNA followed by whole mount in situ hybridizations of over-represented transcripts encoding aphid-specific orphan proteins. We identified a novel class of genes that encode small proteins with signal peptides, which are often cysteine-rich, that are over-represented in bacteriocytes. These genes are first expressed at a developmental time point coincident with the incorporation of symbionts strictly in the cells that contribute to the bacteriocyte and this bacteriocyte-specific expression is maintained throughout the aphid's life. The expression pattern suggests that recently evolved secretion proteins act within bacteriocytes, perhaps to mediate the symbiosis with beneficial bacterial partners, which is reminiscent of the evolution of novel cysteine-rich secreted proteins of leguminous plants that regulate nitrogen-fixing endosymbionts.
6
Chong, Rebecca A., and Nancy A. Moran. "Intraspecific genetic variation in hosts affects regulation of obligate heritable symbionts." Proceedings of the National Academy of Sciences 113, no. 46 (October 31, 2016): 13114–19. http://dx.doi.org/10.1073/pnas.1610749113.
Full textAbstract:
Symbiotic relationships promote biological diversification by unlocking new ecological niches. Over evolutionary time, hosts and symbionts often enter intimate and permanent relationships, which must be maintained and regulated for both lineages to persist. Many insect species harbor obligate, heritable symbiotic bacteria that provision essential nutrients and enable hosts to exploit niches that would otherwise be unavailable. Hosts must regulate symbiont population sizes, but optimal regulation may be affected by the need to respond to the ongoing evolution of symbionts, which experience high levels of genetic drift and potential selection for selfish traits. We address the extent of intraspecific variation in the regulation of a mutually obligate symbiosis, between the pea aphid (Acyrthosiphon pisum) and its maternally transmitted symbiont, Buchnera aphidicola. Using experimental crosses to identify effects of host genotypes, we measured symbiont titer, as the ratio of genomic copy numbers of symbiont and host, as well as developmental time and fecundity of hosts. We find a large (>10-fold) range in symbiont titer among genetically distinct aphid lines harboring the same Buchnera haplotype. Aphid clones also vary in fitness, measured as developmental time and fecundity, and genetically based variation in titer is correlated with host fitness, with higher titers corresponding to lower reproductive rates of hosts. Our work shows that obligate symbiosis is not static but instead is subject to short-term evolutionary dynamics, potentially reflecting coevolutionary interactions between host and symbiont.
7
Burke, Gaelen R., Benjamin B. Normark, Colin Favret, and Nancy A. Moran. "Evolution and Diversity of Facultative Symbionts from the Aphid Subfamily Lachninae." Applied and Environmental Microbiology 75, no. 16 (June 19, 2009): 5328–35. http://dx.doi.org/10.1128/aem.00717-09.
Full textAbstract:
ABSTRACT Many aphids harbor a variety of endosymbiotic bacteria. The functions of these symbionts can range from an obligate nutritional role to a facultative role in protecting their hosts against environmental stresses. One such symbiont is “Candidatus Serratia symbiotica,” which is involved in defense against heat and potentially also in aphid nutrition. Lachnid aphids have been the focus of several recent studies investigating the transition of this symbiont from a facultative symbiont to an obligate symbiont. In a phylogenetic analysis of Serratia symbionts from 51 lachnid hosts, we found that diversity in symbiont morphology, distribution, and function is due to multiple independent origins of symbiosis from ancestors belonging to Serratia and possibly also to evolution within distinct symbiont clades. Our results do not support cocladogenesis of “Ca. Serratia symbiotica” with Cinara subgenus Cinara species and weigh against an obligate nutritional role. Finally, we show that species belonging to the subfamily Lachninae have a high incidence of facultative symbiont infection.
8
Macdonald, Sandy J., Gavin H. Thomas, and Angela E. Douglas. "Waste not, want not: Nitrogen recycling by metabolic pathways shared between an animal and its symbiotic bacteria." Biochemist 35, no. 4 (August 1, 2013): 20–24. http://dx.doi.org/10.1042/bio03504020.
Full textAbstract:
A combined computational and experimental analysis of metabolism in the symbiosis between the pea aphid and its obligate endosymbiont Buchnera aphidicola redefines existing notions of symbiotic nitrogen recycling. As a consequence of metabolic pathways shared between the partners, the insect recycles waste ammonia into essential amino acids (EAAs) that are lacking in its diet of sugar-rich but nitrogen-poor plant phloem sap.
9
Pérez-Brocal, Vicente, Rosario Gil, Andrés Moya, and Amparo Latorre. "New Insights on the Evolutionary History of Aphids and Their Primary Endosymbiont Buchnera aphidicola." International Journal of Evolutionary Biology 2011 (February 16, 2011): 1–9. http://dx.doi.org/10.4061/2011/250154.
Full textAbstract:
Since the establishment of the symbiosis between the ancestor of modern aphids and their primary endosymbiont, Buchnera aphidicola, insects and bacteria have coevolved. Due to this parallel evolution, the analysis of bacterial genomic features constitutes a useful tool to understand their evolutionary history. Here we report, based on data from B. aphidicola, the molecular evolutionary analysis, the phylogenetic relationships among lineages and a comparison of sequence evolutionary rates of symbionts of four aphid species from three subfamilies. Our results support previous hypotheses of divergence of B. aphidicola and their host lineages during the early Cretaceous and indicate a closer relationship between subfamilies Eriosomatinae and Lachninae than with the Aphidinae. They also reveal a general evolutionary pattern among strains at the functional level. We also point out the effect of lifecycle and generation time as a possible explanation for the accelerated rate in B. aphidicola from the Lachninae.
10
Shang, Feng, Jinzhi Niu, Bi-Yue Ding, and Jin-Jun Wang. "Comparative Insight into the Bacterial Communities in Alate and Apterous Morphs of Brown Citrus Aphid (Hemiptera: Aphididae)." Journal of Economic Entomology 113, no. 3 (February 10, 2020): 1436–44. http://dx.doi.org/10.1093/jee/toaa016.
Full textAbstract:
Abstract Wing polyphenism (alate and apterous morphs) in aphids is a trade-off between dispersal and reproduction. How bacterial communities are associated with wing polyphenism in aphids is still not clearly understood. This study used 16S rRNA sequencing to examine the differences in diversity of the bacterial community between alate and apterous morphs in Aphis citricidus, the main vector of the Citrus tristeza virus. Eighty-one operational taxonomic units (OTUs) belonging to 37 orders, 34 classes, and 13 phyla were identified from all samples. Among these OTUs, Wolbachia (79.17%), Buchnera (17.64%), and Pseudomonas (2.99%) were the dominant bacterial genera. The diversity of symbionts varied between the two morphs; apterous morphs had more bacterial diversity (69 OTUs belonging to 45 families, 21 classes, and 12 phyla) than alate morphs (45 OTUs belonging to 36 families, 15 classes, and 10 phyla). In addition, the abundance of five OTUs was significantly different between two morphs. Among these OTUs, two Pseudomonas species (Pseudomonas_brenneri [OTU21] and unclassified_Pseudomonas [OTU13]) represented a high proportion (3.93% and 2.06%) in alate morphs but were present in low abundance (0.006% and 0.002%) in apterous morphs. RT-qPCR showed consistent results with high-throughput DNA sequencing. The preliminary survey showed the difference in composition and frequency of bacteria between alate and apterous morphs. Thus, the results contribute to anew insight of microorganisms that may be involved in wing dimorphism and helpful for controlling the dispersal of this pest through artificial elimination or reinfection of bacterial symbionts or targeting symbiosis-related host genes by RNA interference in future.
Dissertations / Theses on the topic "Aphid bacteria symbiosis"
1
Simonet, Pierre. "Processus cellulaires et moléculaires impliqués dans l’homéostasie bactériocytaire chez le puceron du pois Acyrthosiphon pisum." Thesis, Lyon, 2016. http://www.theses.fr/2016LYSEI135/document.
Full textAbstract:
Les associations symbiotiques constituent un moteur majeur de la diversification écologique et évolutive des organismes métazoaires. Chez les insectes, elles ont conduit, au cours de l’évolution, à l’émergence d’un nouveau type cellulaire spécialisé dans l’hébergement des bactéries symbiotiques, les bactériocytes. Ces cellules demeurent une énigme fascinante de la symbiose, les processus déterminant leur développement, leur morphogenèse et leur dégénérescence restant encore méconnus. Dans cette étude, nous avons utilisé la symbiose entre le puceron Acyrthosiphon pisum et son endosymbiote obligatoire, Buchnera aphidicola, comme système modèle. En combinant des approches inédites de cytométrie en flux et d’imagerie cellulaire, nous avons démontré une régulation fine et coordonnée des dynamiques de croissance et de dégénérescence des bactériocytes et des symbiotes bactériens, en accord avec les besoins physiologiques de l’insecte. De l’embryon à l’âge adulte, les cellules symbiotiques croissent de manière exponentielle, répondant aux besoins nutritionnels de l’hôte qui nécessite pour son développement de grandes quantités d’acides aminés essentiels produits par le métabolisme bactériocytaire. Avec la sénescence du puceron, les bactériocytes diminuent en nombre, en taille et subissent une dégénérescence progressive. Ce processus dégénératif ne montre pas les signes classiques de l’apoptose. Il résulte d’une hypervacuolisation cytoplasmique, dérivée du réticulum endoplasmique, déclenchant une cascade de réponses cellulaires dont l’activation des voies autophagique et lysosomale. Ce phénomène de mort cellulaire non-apoptotique en deux étapes, rappelant la paraptosis, n’a jamais été décrit chez les insectes et sa découverte ouvre la voie à l’étude des régulations agissant sur l’homéostasie bactériocytaire. Dans le dernier volet de cette thèse, nous avons procédé à l’étude fonctionnelle du gène PAH, fortement exprimé dans les bactériocytes et potentiellement impliqué dans la régulation de leur homéostasie. Les résultats obtenus n’ont pas révélé de phénotype bactériocytaire, après ARN interférence, mais ont permis de démontrer un rôle essentiel de ce gène dans la morphogenèse des insectesSymbiotic associations constitute a driving force in the ecological and evolutionary diversification of metazoan organisms. Over the evolution, they have led to the emergence, in insects, of a novel eukaryotic cell type, the bacteriocytes, specialized in harboring symbiotic bacteria. These cells constitute a fascinating enigma in cell biology, as the processes underpinning their development, morphogenesis and degeneration remain still unsolved. In my PhD thesis, we have used the nutritional symbiosis between the aphid, Acyrthosiphon pisum, and its obligate endosymbiont, Buchnera aphidicola, as a model system. We have first developed a novel approach for counting symbiotic bacteria, based on flow cytometry, and showed that the endosymbiont population increases exponentially throughout aphid nymphal development, with a growing rate that has never been characterized by indirect molecular techniques. Using histology and imaging techniques, we have shown that bacteriocytes also increase significantly in number and size during nymphal development. Once adulthood is reached, the dynamics of symbiont and host cells is reversed: the number of endosymbionts decreases progressively and bacteriocytes start to degenerate. These results show a coordination of the cellular dynamics between bacteriocytes and primary symbionts, and reveal a fine-tuning of aphid symbiotic cells to the nutritional demand imposed by the host physiology throughout development. Interestingly, the degenerative process that bacteriocytes undergo with aging exhibits morphological features distinct from the evolutionary conserved apoptotic cell deaths. It originates from an extensive ER-derived hypervacuolation, triggering a cascade of cellular stress responses including the activation of autophagy and lysosomal pathways. This stepwise non-apoptotic cell death, sharing several features with paraptosis, has hitherto never been characterized in insects and its discovery opens the way to the identification of the molecular mechanisms acting on bacteriocyte homeostasis. In the last part of this PhD project, we have proceeded to the characterization of the PAH gene functions in aphid physiology, using an RNA interference (RNAi) approach. Our results show that, even though this gene is highly expressed in bacteriocytes, it is not involved in the regulation of their homeostasis. Nevertheless, we have demonstrated a new role for this metabolic gene in insect embryonic development and morphogenesis
2
Lukasik, Piotr. "The facultative endosymbionts of grain aphids and the horizontal transfer of ecologically important traits." Thesis, University of Oxford, 2011. http://ora.ox.ac.uk/objects/uuid:6aedd183-2dde-4099-a74a-e3f7c909546a.
Full textAbstract:
Insects are often infected with facultative endosymbiotic bacteria, which can have a range of important ecological effects. The grain aphid, Sitobion avenae, harbours diverse facultative symbionts, which suggests their importance in grain aphid biology. This thesis attempts to explain the ecological roles of the facultative endosymbionts in S. avenae. It also examines the question of whether the horizontal transmission of symbionts between aphid clones and species can be important for shaping the ecology and evolution of multi-species aphid communities. Novel techniques developed for research with the grain aphid study system are presented. Grain aphid clones vary in their tolerance to low temperatures, but this trait is not affected by their facultative endosymbionts. Strains of a symbiont Hamiltonella defensa do not protect grain aphids from hymenopterous parasitoids, regardless of the host genotype. However, experienced parasitoid females preferentially oviposit in aphids which do not harbour symbionts. Comparison of the fitness consequences of infection with the same Hamiltonella strains in their original and in novel grain aphid host clones reveal no consistent differences. Symbiont strains establish easily following artificial transfer between clones of the grain aphid, but the symbionts transferred from other aphid species form less stable infections. Hamiltonella strains do not affect the fecundity of their grain aphid host clones regardless of their host species of origin, but also do not generally confer protection against parasitoids. There are no clear patterns in the distribution of parasitoid-resistant phenotypes across phylogenetic trees of Hamiltonella and its bacteriophage APSE. Strains of four unrelated species of endosymbionts, Rickettsia, Spiroplasma, Rickettsiella and Regiella, confer the same pathogen-resistant phenotype to a single pea aphid clone. The same symbiont strains can confer resistance to clones of two different aphid species. Some strains in multiple infections may compensate for the costs of infections with other symbionts. The importance of these results for understanding the ecological and evolutionary role of facultative endosymbionts in aphids and other insects are discussed, and directions for further research are proposed.
3
Humphreys, Natalie J. "Symbiotic bacteria and aphid reproduction." Thesis, University of York, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.337631.
Full text
4
Adams, Diane. "Host plant effects on an aphid-bacterial symbiosis." Thesis, University of York, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.337152.
Full text
5
Whithead, Lynne F. "The symbiotic bacteria of the pea aphid, Acyrthosiphon pisum." Thesis, University of Oxford, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.333293.
Full text
6
Oliver, Kerry M. "The role of pea aphid bacterial symbionts in resistance to parasitism." Diss., Tucson, Arizona : University of Arizona, 2005. http://etd.library.arizona.edu/etd/GetFileServlet?file=file:///data1/pdf/etd/azu%5Fetd%5F1031%5F1%5Fm.pdf&type=application/pdf.
Full text
7
Russell, Jacob Adam. "Coevolution and consequences of symbioses between aphids and maternally transmitted bacteria." Diss., The University of Arizona, 2004. http://hdl.handle.net/10150/280740.
Full textAbstract:
Symbiosis is a prevalent phenomenon among organisms throughout the tree of life, including the insects which often harbor maternally transmitted bacteria. Aphids engage in symbiotic interactions with several maternally transmitted bacteria, and many are known to associate with microbes known as secondary symbionts. These bacteria are typically not essential from the aphid's perspective, and until recently little was known about their roles in aphid biology or the coevolutionary histories of these symbioses. I have addressed these mysteries in this dissertation, through use of molecular and experimental analyses. My findings reveal that secondary symbionts are diverse and infect members of numerous aphid and insect taxa. Though they are maternally transmitted, their distributions can be attributed to occasional horizontal transmission among species. Consequences of symbiosis were observed at genomic levels, with "T-" and "U-type" symbionts exhibiting accelerated evolution in their 16S rRNA sequences. The "R-type" symbiont, in contrast, has not experienced accelerated substitution rates, though it does show a recent trend toward increased AT content, as observed for other symbiotic bacteria. Molecular and phylogenetic evidence presented in this dissertation suggest that secondary symbionts are generalists, capable of infecting numerous aphid hosts. Here, I also present experimental evidence in support of this hypothesis, demonstrating that two of three horizontally transferred symbionts are passed on maternally, at high efficiency, in a novel host, Acyrthosiphon pisum. However, not all efficiently transmitted symbionts would be expected to persist in populations of A. pisum, as some reduce aphid fitness. Finally, evidence obtained from my research and previous experimental and theoretical studies suggests that secondary symbionts should improve aphid fitness, though benefits may not accrue in all environments. Here, I examine the effects of temperature on the fitness effects induced by R-, T-, and U-type symibionts, finding that the R- and T-types confer benefits in aphids exposed to high temperatures, compared to slight and even non-existent effects on A. pisum reared under permissive temperatures. The U-type reduced fitness of aphids reared under high temperatures, revealing a potential cost to symbiont infection that could help to explain intermediate infection frequencies.
8
Birkle, Lucinda. "A molecular characterisation of the mitochondria and bacteria of the pea aphid, Acyrthosiphon pisum." Thesis, University of York, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.387619.
Full text
9
Hansen, Thorsten. "IDENTIFYING MECHANISMS OF HOST PLANT SPECIALIZATION IN APHIS CRACCIVORA AND ITS BACTERIAL SYMBIONTS." UKnowledge, 2018. https://uknowledge.uky.edu/entomology_etds/42.
Full textAbstract:
Many insects form close relationships with microbial symbionts. Insect symbionts can provide novel phenotypes to their hosts, including influencing dietary breadth. In the polyphagous cowpea aphid, Aphis craccivora, the facultative symbiont Arsenophonus improves aphid performance on one host plant (locust), but decreases performance on other plants. The goal of my thesis was to investigate the mechanism by which Arsenophonus facilitates use of locust. First, I assembled an Aphis craccivora-Arsenophonus-Buchnera reference transcriptome to conduct RNAseq analysis, comparing gene expression in aphids feeding on locust and fava, with and without Arsenophonus infection. Overall, few transcripts were differentially expressed. However, genes that were differentially expressed mapped to a variety of processes, including metabolism of glucose, cytoskeleton regulation, cold and drought regulation, and B-vitamin synthesis. These results imply that Arsenophonus is producing B-vitamins, which might be deficient in locust. In a second set of experiments, I used qPCR to test whether symbiont function across host plants might be mediated by bacterial titer. I measured relative Arsenophonus abundance across plants, and found Arsenophonus titer was variable, but generally greater on locust than fava. In summary, my results suggest that Arsenophonus synthesis of B-vitamins should be further investigated and may be mediated by bacterial titer.
10
Ali, Sajjad [Verfasser], Stefan [Akademischer Betreuer] Vidal, Petr [Akademischer Betreuer] Karlovsky, and Stefan [Akademischer Betreuer] Schütz. "Exploring the interactions of bacterial secondary symbionts (BSS) in wheat aphids, Sitobion avenae F. with parasitoids / Sajjad Ali. Betreuer: Stefan Vidal. Gutachter: Petr Karlovsky ; Stefan Schütz." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2015. http://d-nb.info/1079384561/34.
Full textBooks on the topic "Aphid bacteria symbiosis"
1
Kirchman, David L. Symbioses and microbes. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780198789406.003.0014.
Full textAbstract:
The book ends with a chapter devoted to discussing interactions between microbes and higher plants and animals. Symbiosis is sometimes used to describe all interactions, even negative ones, between organisms in persistent, close contact. This chapter focuses on interactions that benefit both partners (mutualism), or one partner while being neutral to the other (commensalism). Microbes are essential to the health and ecology of vertebrates, including Homo sapiens. Microbial cells outnumber human cells on our bodies, aiding in digestion and warding off pathogens. In consortia similar to the anaerobic food chain of anoxic sediments, microbes are essential in the digestion of plant material by deer, cattle, and sheep. Different types of microbes form symbiotic relationships with insects and help to explain their huge success in the biosphere. Protozoa are crucial for wood-boring insects, symbiotic bacteria in the genus Buchnera provide sugars to host aphids while obtaining essential amino acids in exchange, and fungi thrive in subterranean gardens before being harvested for food by ants. Symbiotic dinoflagellates directly provide organic material to support coral growth in exchange for ammonium and other nutrients. Corals are now threatened worldwide by rising oceanic temperatures, decreasing pH, and other human-caused environmental changes. At hydrothermal vents in some deep oceans, sulfur-oxidizing bacteria fuel an entire ecosystem and endosymbiotic bacteria support the growth of giant tube worms. Higher plants also have many symbiotic relationships with bacteria and fungi. Symbiotic nitrogen-fixing bacteria in legumes and other plants fix more nitrogen than free-living bacteria. Fungi associated with plant roots (“mycorrhizal”) are even more common and potentially provide plants with phosphorus as well as nitrogen. Symbiotic microbes can provide other services to their hosts, such as producing bioluminescence, needed for camouflage against predators. In the case of the bobtail squid, bioluminescence is only turned on when populations of the symbiotic bacteria reach critical levels, determined by a quorum sensing mechanism.
Book chapters on the topic "Aphid bacteria symbiosis"
1
Adams, D., T. L. Wilkinson, and A. E. Douglas. "The aphid-bacterial symbiosis: a comparison between pea aphids and black bean aphids." In Proceedings of the 9th International Symposium on Insect-Plant Relationships, 275–78. Dordrecht: Springer Netherlands, 1996. http://dx.doi.org/10.1007/978-94-009-1720-0_62.
Full text
2
"Bacteria and Other Symbionts of Aphids." In Insect Symbiosis, 41–56. CRC Press, 2003. http://dx.doi.org/10.1201/9780203009918-7.
Full text
3
Douglas, Angela. "Buchnera Bacteria And Other Symbionts Of Aphids." In Insect Symbiosis, 23–38. CRC Press, 2003. http://dx.doi.org/10.1201/9780203009918.ch2.
Full text
4
"Bacterial Symbionts of Aphids (Hemiptera: Aphididae)." In Biology and Ecology of Aphids, 110–35. CRC Press, 2016. http://dx.doi.org/10.1201/b19967-7.
Full text