| plasmid-encoded anthranilate synthase (trpeg) in buchnera aphidicola from aphids of the family pemphigidae. | buchnera aphidicola is an obligate intracellular symbiont of aphids. one of its proposed functions is the synthesis of essential amino acids, nutrients required by aphids but deficient in their diet of plant phloem sap. the genetic organization of the tryptophan pathway in buchnera from proliferous aphids of the family aphididae has previously been shown to reflect a capacity to overproduce this essential amino acid (c.-y. lai, l. baumann, and p. baumann, proc. natl. acad. sci. usa 91:3819-3823, ... | 1999 | 9872768 |
| molecular characterization of the leucine cluster in buchnera sp. strain psy, a primary endosymbiont of the aphid pemphigus spyrothecae. | buchnera strains from most aphid subfamilies studied to date have been found to carry the leucine gene cluster (leua, -b, -c, and -d) on a plasmid, an organization unique among bacteria. here, however, we demonstrate a classical chromosomal location of the cluster in buchnera sp. strain psy from the aphid pemphigus spyrothecae (subfamily pemphiginae). the genes that flank leuabcd in buchnera sp. strain psy appear to be adjacent in the genome of buchnera sp. strain aps, a strain carrying a leucin ... | 2002 | 11976137 |
| specialised placement of morphs within the gall of the social aphid pemphigus spyrothecae. | the strategic placement and aggregation of certain castes within the nests of eusocial insects such as bees and ants results in complex colonies that enjoy increased fitness through improved efficiency of social tasks. to examine if this advanced social phenomenon might apply to social aphids, the location of the numerous morphs within the nests (plant galls) of the aphid species pemphigus spyrothecae was examined. | 2007 | 17298667 |
| soldiers effectively defend aphid colonies against predators in the field | morphologically specialized soldiers occur in more than 50 aphid species in the families pemphigidae and hormaphididae. to study the effectiveness of soldiers of the gall-forming aphid, pemphigus spyrothecae pass., in protecting their galls against natural levels of predation, we manipulated the proportions of soldiers and non-soldiers in sets of galls still attached to poplar trees in the field. galls with 50 soldiers and 50 non-soldiers were approximately 10 times less likely to be attacked by ... | 1998 | 9514674 |
| changes in clonal poplar leaf chemistry caused by stem galls alter herbivory and leaf litter decomposition. | gall-inducing insects are highly specialized herbivores that modify the phenotype of their host plants. beyond the direct manipulation of plant morphology and physiology in the immediate environment of the gall, there is also evidence of plant-mediated effects of gall-inducing insects on other species of the assemblages and ecosystem processes associated with the host plant. we analysed the impact of gall infestation by the aphid pemphigus spirothecae on chemical leaf traits of clonal lombardy p ... | 2013 | 24260333 |
| clonal mixing in the soldier-producing aphid pemphigus spyrothecae (hemiptera: aphididae). | illuminating the genetic relationships within soldier-producing aphid colonies is an essential element of any attempt to explain the evolution of the altruistic soldier caste. pemphigus spyrothecae is a soldier-producing aphid that induces galls on the leaf petioles of its host (trees of the genus populus). at least a quarter of the aphids within the clonally produced gall population are morphologically and behaviourally distinct first-instar soldiers that defend the gall population from predati ... | 2002 | 12144671 |
| microsatellite loci for studying clonal mixing, population structure and inbreeding in a social aphid, pemphigus spyrothecae (hemiptera: pemphigidae). | | 2000 | 10972790 |