Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

Symbiosis00:58

Symbiosis

37.9K
Symbiotic relationships are long-term, close interactions between individuals of different species that affect the distribution and abundance of those species. When a relationship is beneficial to both species, this is called mutualism. When the relationship is beneficial to one species but neither beneficial nor harmful to the other species, this is called commensalism. When one organism is harmed to benefit another, the relationship is known as parasitism. These types of relationships often...
37.9K
Defenses Against Pathogens and Herbivores02:26

Defenses Against Pathogens and Herbivores

29.8K
Plants present a rich source of nutrients for many organisms, making it a target for herbivores and infectious agents. Plants, though lacking a proper immune system, have developed an array of constitutive and inducible defenses to fend off these attacks.
29.8K
Epiphytes, Parasites, and Carnivores02:40

Epiphytes, Parasites, and Carnivores

17.0K
Plants often form mutualistic relationships with soil-dwelling fungi or bacteria to enhance their roots’ nutrient uptake ability. Root-colonizing fungi (e.g., mycorrhizae) increase a plant’s root surface area, which promotes nutrient absorption. While root-colonizing, nitrogen-fixing bacteria (e.g., rhizobia) convert atmospheric nitrogen (N2) into ammonia (NH3), making nitrogen available to plants for various biological functions. For example, nitrogen is essential for the...
17.0K
Predator-Prey Interactions02:39

Predator-Prey Interactions

22.0K
Predators consume prey for energy. Predators that acquire prey and prey that avoid predation both increase their chances of survival and reproduction (i.e., fitness). Routine predator-prey interactions elicit mutual adaptations that improve predator offenses, such as claws, teeth, and speed, as well as prey defenses, including crypsis, aposematism, and mimicry. Thus, predator-prey interactions resemble an evolutionary arms race.
22.0K
Frequency-dependent Selection01:21

Frequency-dependent Selection

24.4K
When the fitness of a trait is influenced by how common it is (i.e., its frequency) relative to different traits within a population, this is referred to as frequency-dependent selection. Frequency-dependent selection may occur between species or within a single species. This type of selection can either be positive—with more common phenotypes having higher fitness—or negative, with rarer phenotypes conferring increased fitness.
24.4K
Transduction01:16

Transduction

2.2K
Among the three main modes of HGT—transformation, conjugation, and transduction—transduction is unique in that it is mediated by bacteriophages, or bacterial viruses.Transduction occurs in two ways. Generalized transduction occurs during the lytic cycle of a bacteriophage infection. In this process, bacteriophages infect bacterial cells, replicate within them, and ultimately cause cell lysis, releasing newly assembled virions. Occasionally, random fragments of the bacterial genome...
2.2K

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Elevated Temperatures Disrupt Wolbachia-Induced Feminisation and Reshape Microbial Community Dynamics Across Generations in a Spider Host.

Molecular ecology·2026
Same author

Emergent symbiont strains provide thermally robust protection against co-evolved and novel parasitoids of introduced pea aphids.

The ISME journal·2026
Same author

Phage toxin variants are linked to protection specificity in a defensive symbiont.

Molecular biology and evolution·2026
Same author

Ecological Mercenaries: Why Aphids Remain Premier Models for the Study of Ecological Symbiosis.

Insects·2025
Same author

The ecology, evolution, and physiology of Cardinium: a widespread heritable endosymbiont of invertebrates.

FEMS microbiology reviews·2025
Same author

Wolbachia Feminises a Spider Host With Assistance From Co-Infecting Symbionts.

Environmental microbiology·2025

Related Experiment Video

Updated: Mar 8, 2026

Maintaining Biological Cultures and Measuring Gene Expression in Aphis nerii: A Non-model System for Plant-insect Interactions
07:20

Maintaining Biological Cultures and Measuring Gene Expression in Aphis nerii: A Non-model System for Plant-insect Interactions

Published on: August 31, 2018

8.1K

Aphid Heritable Symbiont Exploits Defensive Mutualism.

Matthew R Doremus1, Kerry M Oliver2

  • 1Department of Entomology, University of Georgia, Athens, Georgia, USA mdoremus@email.arizona.edu.

Applied and Environmental Microbiology
|February 5, 2017
PubMed
Summary

The X-type bacteria in pea aphids provides no protection and causes harm. It survives by hitchhiking on the benefits of another bacteria, Hamiltonella defensa.

Keywords:
Hamiltonella defensaPAXSentomopathogenic fungiheat stressheritable symbiontsparasitoidspea aphid resistance

More Related Videos

Methods for the Extraction of Endosymbionts from the Whitefly Bemisia tabaci
07:28

Methods for the Extraction of Endosymbionts from the Whitefly Bemisia tabaci

Published on: June 19, 2017

10.4K
A Visual Guide for Studying Behavioral Defenses to Pathogen Attacks in Leaf-Cutting Ants
08:10

A Visual Guide for Studying Behavioral Defenses to Pathogen Attacks in Leaf-Cutting Ants

Published on: October 12, 2018

11.9K

Related Experiment Videos

Last Updated: Mar 8, 2026

Maintaining Biological Cultures and Measuring Gene Expression in Aphis nerii: A Non-model System for Plant-insect Interactions
07:20

Maintaining Biological Cultures and Measuring Gene Expression in Aphis nerii: A Non-model System for Plant-insect Interactions

Published on: August 31, 2018

8.1K
Methods for the Extraction of Endosymbionts from the Whitefly Bemisia tabaci
07:28

Methods for the Extraction of Endosymbionts from the Whitefly Bemisia tabaci

Published on: June 19, 2017

10.4K
A Visual Guide for Studying Behavioral Defenses to Pathogen Attacks in Leaf-Cutting Ants
08:10

A Visual Guide for Studying Behavioral Defenses to Pathogen Attacks in Leaf-Cutting Ants

Published on: October 12, 2018

11.9K

Area of Science:

  • Microbiology
  • Ecology
  • Evolutionary Biology

Background:

  • Heritable bacterial symbionts significantly influence host organisms, particularly insects.
  • Pea aphids (Acyrthosiphon pisum) are a model system for studying heritable facultative symbionts (HFS), with known HFS conferring stress resistance.
  • X-type, a common HFS, is typically found superinfecting aphids with Hamiltonella defensa, which protects against parasitic wasps.

Purpose of the Study:

  • To investigate the benefits and costs of X-type HFS infection in pea aphids, both as a single infection and in superinfection with H. defensa.
  • To determine if X-type provides any protective benefits against common aphid threats.
  • To elucidate the maintenance strategy of X-type within aphid populations.

Main Methods:

  • Experimental pea aphid lines with all HFS infection combinations were created using a uniform aphid genotype.
  • Aphids were challenged with parasitoid wasps, fungal pathogens, and thermal stress to assess protection.
  • Component fitness assays were conducted to quantify the fitness costs and benefits of X-type infection.

Main Results:

  • X-type infection alone did not confer protection against parasitoid wasps, fungal pathogens, or thermal stress.
  • X-type infection resulted in significant fitness costs for the aphids.
  • These fitness costs were ameliorated when aphids were superinfected with H. defensa.

Conclusions:

  • X-type HFS appears to be an exploitative symbiont that benefits from the mutualistic relationship between aphids and H. defensa.
  • X-type is maintained in populations primarily by hitchhiking on the benefits provided by H. defensa.
  • Exploitative symbionts can negatively impact mutualistic symbioses and influence community dynamics.