Transfer of aphid secondary symbionts within sympatric insectcommunities and the effect of ingesting symbionts on ladybirdbeetles 公开
Kamins, Alexandra Orion (2009)
Published
Abstract
Aphids cannot survive on their limited diet of plant phloem without the help of their primary
symbiotic bacterium, Buchnera. In addition to this obligate relationship, a number of
facultative symbionts can inhabit this sap-sucking insect. While efficient transmission from
mother to daughter is readily seen in the lab for both types, secondary symbionts are thought
to undergo horizontal transfer across species in the field. Genetic comparisons suggest these
jumps may even occur between very distantly related species, such as whiteflies or ladybirds.
Such horizontal transfer could play a critical role in both understanding the colonization of
new insect lineages with novel bacteria and in the general understanding of bacterial
migration. I explored the transfer among insects in the aphid community, screening field
samples of sympatric ants, ladybirds and aphids for three common aphid secondary
symbionts and conducting feeding experiments with live ladybirds. I found that ladybird
larvae fed aphids with symbionts were half as likely to die as larvae fed aphids without
symbionts, suggesting there is an advantage to consuming symbionts. There was decrease in
the persistence over time of the symbiont Serratia symbiotica in adult ladybird beetles fed
aphids with the bacteria, until no bacterial DNA was seen in the ladybirds after one week. No
ants or ladybirds were found in the field with any of the three main aphid symbionts,
suggesting that horizontal transfer is a rare event. Still, ingestion may need to be considered
as a route of symbiont acquisition.
Table of Contents
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Figure 1 Seasonal cycle of a pea aphid . . . . . . . . . . . . . . . . 2
Methods. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16
Figure 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Figure 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Figure 4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Figure 5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Figure 6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Figure 7 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Figure 8 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Figure 9. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Table 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Discussion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Future Directions and Concluding Remarks . . . . . . . . . 30
Appendix A . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
Appendix B . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
References. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .34
About this Honors Thesis
School | |
---|---|
Department | |
Degree | |
Submission | |
Language |
|
Research Field | |
关键词 | |
Committee Chair / Thesis Advisor | |
Committee Members |
Primary PDF
Thumbnail | Title | Date Uploaded | Actions |
---|---|---|---|
|
Transfer of aphid secondary symbionts within sympatric insectcommunities and the effect of ingesting symbionts on ladybirdbeetles () | 2018-08-28 13:13:40 -0400 |
|
Supplemental Files
Thumbnail | Title | Date Uploaded | Actions |
---|