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The evolution of entomopathogeny in nematodes
V J Trejo-Meléndez1,2, J Ibarra-Rendón3, J Contreras-Garduño1,4
1Edificio de Investigación I, ENES, Unidad Morelia, UNAM Morelia Michoacán Mexico.
Ecology and Evolution
|February 14, 2024
Summary
The study proposes broadening the definition of entomopathogenic nematodes to include diverse Rhabditida species. This reflects a convergent evolution of parasitism, offering insights into host-parasite interactions.
Area of Science:
- Nematology
- Evolutionary Biology
- Parasitology
Background:
- Entomopathogenesis in nematodes is traditionally linked to Steinernematidae and Heterorhabditidae families.
- These nematodes associate with specific entomopathogenic bacteria: Xenorhabdus and Photorhabdus.
- Nematodes from other families with entomopathogenic bacteria are often excluded from the 'entomopathogenic nematode' classification.
Purpose of the Study:
- To propose an expanded definition of entomopathogenic nematodes.
- To explore the convergent evolution of entomopathogenesis within the order Rhabditida.
- To understand the ecological and evolutionary drivers of parasitism in nematodes.
Main Methods:
- Literature review and synthesis of existing research on nematode parasitism.
- Ecological and evolutionary analysis of nematode lifestyles and bacterial associations.
- Comparative study of nematode families within the order Rhabditida.
Main Results:
- The order Rhabditida exhibits ecological and evolutionary properties favoring convergent evolution of entomopathogenesis.
- Diverse nematode lifestyles (saprotrophic, phoretic, necromenic) may represent early stages of entomopathogenic specialization.
- Existing criteria for 'entomopathogenic nematodes' may be too narrow.
Conclusions:
- The term 'entomopathogenic nematode' should be expanded to encompass diverse Rhabditida lineages.
- Entomopathogenesis appears to be a convergent trait in Nematoda, evolving independently in various families.
- Further research is needed to validate the entomopathogenic capabilities of newly considered species.
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