How the pine seeds attach to/detach from the pine cone scale?

ABSTRACT

One of the primary purposes of pine cones is the protection and distant dispersal of pine seeds. Pine cones open and release their embedded seeds on dry and windy days for long-distance dispersal. In this study, how the pine seeds attach to/detach from the pine cone scale for efficient seed dispersal was experimentally investigated by using an X-ray micro-imaging technique. The cone and seeds adhere to each other in the presence of water, which could be explained by the surface tension and the contact angle hysteresis. Otherwise, without water, the waterproof seed wing surface permits rapid drying for detach and dispersion. On the other hand, during wildfires, pine cones open their seed racks and detach the pine seeds from pine cones for rapid seed dispersal. Due to these structural advantages, pine seeds are released safely and efficiently in normal conditions. These advantageous structures could be mimicked in practical applications.

KEYWORDS:

• Pine cone
• pine seed
• interaction
• attach
• detach

Acknowledgments

The authors are grateful for valuable assistance with the X-ray imaging experiments performed at the 6C beamlines of the Pohang Accelerator Laboratory (Pohang, Korea).

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This research was financially supported by the Creative Research Initiative (Diagnosis of Biofluid Flow Phenomena and Biomimic Research) of the Ministry of Science, ICT and Future Planning (MSIP) and the National Research Foundation (NRF) of Korea (contract grant number: 2008-0061991). Shyr-Shea Chang was supported by National Institutes of Health, under Ruth L. Kirschstein National Research Service Award (T32-GM008185). Its contents are solely the responsibility of the supported author and do not necessarily represent the official views of the NIH.