Synthesizing selection mosaic theory and host-pathogen theory to explain large-scale pathogen coexistence

Area of Science:

• Ecology
• Evolutionary Biology
• Entomology

Background:

• Selection mosaic theory explains host-pathogen polymorphism via spatial selection but omits population dynamics.
• Classical host-pathogen theory addresses population cycles but not pathogen polymorphism persistence.

Purpose of the Study:

• To synthesize selection mosaic and host-pathogen theories to investigate population cycle effects on pathogen polymorphism.
• To model baculovirus morphotype frequency variation in Douglas-fir tussock moth populations.

Main Methods:

• Developed host-pathogen models integrating selection mosaic and population cycle dynamics.
• Analyzed geographic variation in baculovirus morphotype frequencies.
• Correlated morphotype frequencies with Douglas-fir tree frequency.

Main Results:

• Geographic variation in baculovirus morphotype frequency is linked to Douglas-fir frequency.
• Models combining selection mosaic and population cycles best explain observed morphotype frequency data.
• Population cycles amplify pathogen competition across selection mosaics.

Conclusions:

• Synthesis of selection mosaic and host-pathogen theories provides a robust framework for understanding host-pathogen dynamics.
• Douglas-fir frequency significantly impacts baculovirus morphotype frequencies due to intensified competition.
• A dual-morphotype baculovirus biopesticide is projected to be more effective for pest management.