• Corpus ID: 6575344

eview urning heads : The biology of solar tracking in sunflower oshua

  title={eview urning heads : The biology of solar tracking in sunflower oshua},
  author={P. Vandenbrinka and Evan A. Browna and Stacey L. Harmerb and Benjamin K. Blackmana},
Solar tracking in the common sunflower, Helianthus annuus, is a dramatic example of a diurnal rhythm in plants. During the day, the shoot apex continuously reorients, following the sun’s relative position so that the developing heads track from east to west. At night, the reverse happens, and the heads return and face east in anticipation of dawn. This daily cycle dampens and eventually stops at anthesis, after which the sunflower head maintains an easterly orientation. Although shoot apical… 

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