The Role of Wheat Awns in the Seed Dispersal Unit

  title={The Role of Wheat Awns in the Seed Dispersal Unit},
  author={Rivka Elbaum and Liron Zaltzman and Ingo Burgert and Peter Fratzl},
  pages={884 - 886}
The dispersal unit of wild wheat bears two pronounced awns that balance the unit as it falls. We discovered that the awns are also able to propel the seeds on and into the ground. The arrangement of cellulose fibrils causes bending of the awns with changes in humidity. Silicified hairs that cover the awns allow propulsion of the unit only in the direction of the seeds. This suggests that the dead tissue is analogous to a motor. Fueled by the daily humidity cycle, the awns induce the motility… 

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