Search results for "Aphid"
showing 8 items of 128 documents
Data from: Multi-modal defenses in aphids offer redundant protection and increased costs likely impeding a protective mutualism
2018
1.The pea aphid, Acyrthosiphon pisum, maintains extreme variation in resistance to its most common parasitoid wasp enemy, Aphidius ervi, which is sourced from two known mechanisms: protective bacterial symbionts, most commonly Hamiltonella defensa, or endogenously encoded defenses. We have recently found that individual aphids may employ each defense individually, occasionally both defenses together, or neither. 2.In field populations, Hamiltonella-infected aphids are found at low to moderate frequencies and while less is known about the frequency of resistant genotypes, they show up less often than susceptible genotypes in field collections. To better understand these patterns, we sought t…
A genomic reappraisal of symbiotic function in the aphid/Buchnera symbiosis: reduced transporter sets and variable membrane organisations.
2011
International audience; Buchnera aphidicola is an obligate symbiotic bacterium that sustains the physiology of aphids by complementing their exclusive phloem sap diet. In this study, we reappraised the transport function of different Buchnera strains, from the aphids Acyrthosiphon pisum, Schizaphis graminum, Baizongia pistaciae and Cinara cedri, using the re-annotation of their transmembrane proteins coupled with an exploration of their metabolic networks. Although metabolic analyses revealed high interdependencies between the host and the bacteria, we demonstrate here that transport in Buchnera is assured by low transporter diversity, when compared to free-living bacteria, being mostly bas…
A new species of Rhopalosiphum (Hemiptera, Aphididae) on Chusquea tomentosa (Poaceae, Bambusoideae) from Costa Rica
2012
copyright 2012, Los autores y Zookeys. Datos incluidos por Lisela Moreira Carmona, responsable de depósitos del área de Patógenos y Plagas de Plantas (CIBCM-UCR). The new species Rhopalosiphum chusqueae Pérez Hidalgo & Villalobos Muller, is described from apterous viviparous females caught on Chusquea tomentosa in Cerro de la Muerte (Costa Rica). The identity of the species is supported both by the morphological features and by a molecular phylogenetic analysis based on a fragment of the mitochondrial DNA containing the 5’ region of the cytochrome c oxidase 1 (COI) and on the nuclear gene coding for the Elongation factor-1 alpha (EF1α). The taxonomic position of the new species is discussed…
Identification, characterization and analysis of expression of genes encoding arylalkylamine N-acetyltransferases in the pea aphidAcyrthosiphon pisum
2013
Most organisms exhibit some kind of rhythmicity in their behaviour and/or physiology as an adaptation to the cyclical movements of the Earth. In addition to circadian rhythms, many organisms have an annual rhythmicity in certain activities, such as reproduction, migration or induction of diapause. Current knowledge of the molecular basis controlling seasonal rhythmicity, especially in insects, is scarce. One element that seems to play an essential role in the maintenance of both circadian and seasonal rhythms in vertebrates is the hormone melatonin. In vertebrates, the limiting enzyme in its synthesis is the arylalkylamine N-acetyltransferase (AANAT). Melatonin is also present in insects bu…
Transcriptional study of photoperiodic response in aphids and characterization of candidate photoperiodic photoreceptors
2020
Acyrthosiphon pisum es una especie de pulgón altamente estacional. Durante la estación favorable, únicamente se producen hembras partenogenéticas vivíparas (virginóparas). En otoño, cuando hay menos luz (el fotoperiodo es más corto), A. pisum percibe la diferencia y las virginóparas paren machos y luego hembras sexuadas (ovíparas). Tras aparearse, las ovíparas ponen huevos que resisten el invierno y eclosionan en primavera, reiniciando el ciclo. Algunos mutantes que ocurren de forma natural no responden al fotoperiodo y se reproducen asexualmente durante todo el año. Se denominan anholocíclicos en contraposición a los holocíclicos, que tienen fase sexual. Se desconocen los mecanismos molecu…
Molecular evolution of aphids and their primary (Buchnera sp.) and secondary endosymbionts: Implications for the role of symbiosis in insect evolution
2001
Aphids maintain an obligate, endosymbiotic association with Buchnera sp., a bacterium closely related to Escherichia coli. Bacteria are housed in specialized cells of organ-like structures called bacteriomes in the hemocoel of the aphid and are maternally transmitted. Phylogenetic studies have shown that the association had a single origin, dated about 200-250 million years ago, and that host and endosymbiont lineages have evolved in parallel since then. However, the pattern of deepest branching within the aphid family remains unsolved, which thereby hampers an appraisal of, for example, the role played by horizontal gene transfer in the early evolution of Buchnera. The main role of Buchner…
The genome sequence of Blochmannia floridanus: Comparative analysis of reduced genomes
2003
Bacterial symbioses are widespread among insects, probably being one of the key factors of their evolutionary success. We present the complete genome sequence of Blochmannia floridanus , the primary endosymbiont of carpenter ants. Although these ants feed on a complex diet, this symbiosis very likely has a nutritional basis: Blochmannia is able to supply nitrogen and sulfur compounds to the host while it takes advantage of the host metabolic machinery. Remarkably, these bacteria lack all known genes involved in replication initiation ( dna A, pri A, and rec A). The phylogenetic analysis of a set of conserved protein-coding genes shows that Bl. floridanus is phylogenetically related to Buch…
Dual action of phosphonate herbicides in plants affected by herbivore—Model study on black bean aphid Aphis fabae rearing on broad bean Vicia faba pl…
2008
Abstract The interactions between plants, herbicides and herbivore insects were studied as an aspect of possible side effect of the using of phosphonate herbicides. The experimental system was composed of phosphonate herbicides, broad bean Vicia faba (L.) plants and black bean aphid Aphis fabae (Scopoli). Two means of herbicide application, namely standard spraying and direct introduction of the herbicide into stem via glass capillary, were examined. The results obtained for N-2-piridylaminomethylene bisphosphonic acid and its derivatives show 10 times higher inhibition of the plant growth if glass capillary mode was used. When plants were infested by aphids 24 h after the use of herbicide,…