Masting promotes individual- and population-level reproduction by increasing pollination efficiency

Area of Science:

• Ecology
• Plant reproductive biology
• Forest science

Background:

• Masting is a synchronized, intermittent mass seed production strategy in plants.
• The pollination efficiency hypothesis suggests masting enhances plant reproductive success.
• Previous research lacked long-term, multi-level data to test this hypothesis.

Purpose of the Study:

• To rigorously test the pollination efficiency hypothesis in ponderosa pine (Pinus ponderosa).
• To assess pollination success during mast versus non-mast years using long-term population and individual tree data.

Main Methods:

• Utilized a 20-year dataset monitoring 217 ponderosa pine trees annually.
• Analyzed reproductive investment (male and female function) at the individual tree level.
• Compared population-level and individual-level reproductive output (cone production and maturation) between mast and non-mast years.

Main Results:

• Individual tree investment in male and female reproduction did not differ between mast and non-mast years.
• Mast years showed a higher ratio of mature female cones to male strobili at both population and individual levels.
• A greater conversion rate of unfertilized conelets to mature cones was observed in mast years.

Conclusions:

• Findings provide robust evidence supporting the pollination efficiency hypothesis in ponderosa pine.
• Masting increases reproductive success through enhanced pollination efficiency.
• These benefits have significant ecological and potential evolutionary implications.