Plants exhibit phototropism, the ability to bend towards light, primarily through the action of the hormone auxin. When light is detected, a yellow pigment related to riboflavin acts as a photoreceptor, triggering the migration of auxin from the illuminated side of the stem to the shaded side. This differential distribution of auxin causes the cells on the shady side to elongate more than those on the bright side, resulting in the bending of the plant towards the light source. Auxin also plays a critical role in other growth processes such as gravitropism and apical dominance.
PREREQUISITESBotanists, plant biologists, horticulturists, and anyone interested in understanding plant behavior and growth responses to environmental stimuli.
It is believed that a yellow pigment related to riboflavin acts as a photoreceptor for light.
a. Following reception, plant hormone auxin migrates from bright side to shady side of a stem.
b. How reception of stimulus couples to production of auxin is not yet known.
4. Auxin is also involved in gravitropism, apical dominance, and root and seed development.