Mechanisms of diversification

Project Overview

Phytoplasma diversity is shaped by evolutionary interactions with their plant hosts and insect vectors. A central question in host–parasite evolution is whether diversification arises primarily through repeated host switching or through long-term coevolutionary constraints.

This research theme investigates the evolutionary processes structuring phytoplasma–host associations across global lineages.

Research Questions

• Do phytoplasma–vector associations show phylogenetic congruence?
• Are diversification patterns driven primarily by host switching?
• Is host switching constrained by vector phylogeny?
• What is the frequency and directionality of host-shift events?

Approach

We integrate global phytoplasma sequence data with insect phylogenies to conduct cophylogenetic analyses. Using event-based and distance-based modeling approaches, we quantify congruence between phytoplasma and vector evolutionary histories.

Broader Impact

Understanding the mechanisms underlying phytoplasma diversification improves our ability to anticipate evolutionary emergence, predict novel vector associations, and assess long-term pathogen adaptability under environmental change.