Mating system and pollen gene flow in Mediterranean maritime pine

Area of Science:

• Population Genetics
• Forest Ecology

Background:

• Mating systems are crucial for understanding gene flow and genetic variation in plant populations.
• Mediterranean maritime pine (Pinus pinaster) is an important forest species with implications for conservation and management.

Purpose of the Study:

• To analyze the mating system of Mediterranean maritime pine.
• To identify factors influencing mating patterns and pollen dispersal.
• To fit pollen dispersal kernels for conservation and management applications.

Main Methods:

• Hierarchical analysis of mating patterns using progeny arrays.
• Estimation of outcrossing rates and correlated paternity.
• Fitting pollen dispersal kernels using indirect methods (TwoGener, KinDist) and simulations.

Main Results:

• High outcrossing rates (t(m), t(s) ≈ 0.96) and relatively low correlated paternity (r(p) ≈ 0.018-0.048).
• Significant variation in mating system parameters at the single-tree level, with no population or stand effects.
• Outcrossing rates correlated with tree size (diameter, height); correlated paternity negatively correlated with tree height and crown dimensions.

Conclusions:

• Individual tree characteristics significantly influence mating patterns in maritime pine.
• Pollen dispersal is leptokurtic with mean distances of 78.4–174.4 m.
• Further research is needed to fully understand factors affecting correlated paternity for effective forest management.