Response to light stimulus
Film 29 Response of the sunflower to turn-off and turn-on of light with ca. 70 µmol m-2 s-1 intensity located above the plant. The plant movement is accelerated 2700 times.
Light-off initiates circumnutations or increases their length and evokes depolarisation with ca. 5 mV amplitude.
Light-on results in reduction of the circumnutation length and disturbances in their geometry, frequently including changes in the circumnutation direction and hyperpolarisation with ca. 5 mV amplitude.

Complex relationship between growth and circumnutations in Helianthus annuus stem. Plant Signaling & Behavior 3: 376-380
Stolarz M, Król E, Dziubińska H, Zawadzki T (2008)
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