The evolution of plant virus transmission pathways

Area of Science:

• Plant pathology
• Evolutionary biology
• Mathematical modeling

Background:

• Plant viruses utilize various transmission methods, including seed, pollen, and vectors.
• Understanding the evolutionary dynamics of these pathways is crucial for disease management.

Purpose of the Study:

• To investigate the conditions under which vector transmission renders pollen transmission redundant.
• To determine if evolutionary processes can lead to the coexistence of multiple plant virus transmission pathways.
• To explore the evolutionary trade-offs between different transmission strategies.

Main Methods:

• A semi-discrete mathematical model incorporating pollen, seed, and vector transmission was developed.
• Frequency-dependent and density-dependent transmission rates were assumed for vector and pollen, respectively.
• Ecological stability analysis informed an evolutionary study of transmission trade-offs.

Main Results:

• Trade-off shapes critically influence evolutionary outcomes.
• Concave trade-offs between pollen and vector transmission lead to a stable mix, while convex trade-offs result in bi-stability.
• Pollen transmission can inhibit the evolution of vector transmission.
• Trade-offs between seed and vector transmission can facilitate evolutionary branching and the coexistence of different transmission strains.

Conclusions:

• Evolutionary trade-offs are key drivers of plant virus transmission pathway diversity.
• Multiple transmission routes can coexist depending on specific ecological and evolutionary conditions.
• This research provides theoretical insights into observed patterns of plant virus transmission in nature.