Biology Reference
In-Depth Information
CONCLUDING COMMENTS
Our understanding of the relationship between bacteria and aphids has been transformed over the
last decade, largely through the application of molecular biology. The various bacteria have been
identiÝed and their incidence and characteristics established, principally by molecular techniques.
Molecular approaches have also been crucial to our appreciation of the importance of vertical
transmission and genomic decay in shaping the gene content and capabilities of
Buchnera
.
Most recent studies, however, have concentrated on individual members of the association. A
task for the future is to address interactions between partners. This requires us to view the association
as an interactive relationship, not an assemblage of microbial taxa coexisting in a habitat known
as an aphid. Symbiosis function and aphid traits are inÞuenced by the total complement of micro-
organisms and their interrelationships. What are the nutrients and signals that mediate these diverse
interactions? How should we regard the accessory bacteria Ð as commensals, opportunistic patho-
gens, or Ñhelper bacteriaÒ that are potential replacements for
Buchnera
(Ñprimary symbionts in
waitingÒ), should the latter suffer genomic meltdown? A Ýrm understanding of these interactions
will lead to a better appreciation of this astonishing symbiosis and may provide a basis for novel
approaches to aphid pest management.
ACKNOWLEDGMENTS
Research leading to previously unpublished data was funded by grant GR3/10491 from the Natural
Environment Research Council, U.K.
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