Wind pollination over mesoscale distances: an investigation with Scots pine

Area of Science:

• Ecology
• Evolutionary Biology
• Genetics

Background:

• A significant gap exists between maximum documented airborne pollen transport distances (10^2–10^3 km) and effective wind pollination scales (up to 10^1 km).
• This discrepancy may stem from challenges in detecting long-distance effective pollination events.

Purpose of the Study:

• To investigate effective wind pollination over distances approaching maximum observed physical pollen transport.
• To assess pollen immigration into an isolated Iberian *Pinus sylvestris* remnant.

Main Methods:

• Utilized paternally inherited microsatellite markers to trace pollen origin.
• Employed maximum-likelihood estimation and Monte Carlo simulations to analyze genetic data and parameter uncertainty.

Main Results:

• Detected significant effective pollen flow (up to 4.4%) from a *Pinus sylvestris* population 100 km distant.
• Demonstrated successful pollination over larger scales than previously reported for wind-pollinated trees.

Conclusions:

• The observed effective pollen flow challenges the presumed limitations of wind pollination distances.
• Findings suggest that long-distance pollen transport can lead to successful pollination, impacting ecological processes like metapopulation connectivity and adaptation.