Summary Topic 8 Photoreceptors in plants

Photoreceptors in plants

Phytochrome -

flavering +
germination
short
day plants-flower when low
light
S.I units
Long day plants -



flower when
high light

Day neutral-flower irrespective of day length
Photoperiodism
↳ The recognised by
have
day lenghmorphoprological
is the plants and

effect
Phytochrone red and
phytochrome for red


Pr-650 wavelengt
PEr-730 wavelength
(beyond visual spectrum)
Prabsorbs red
light during the
day
↳
changes it to Pfr
-> In he dark .
Pfr absorbs for red and converts
it to red

↳ slow dark reversion



PFr is he critical active version

time
night important

Short plants low PFr concentration
day need

↳ - hours 17 night
day
PFr
Long day plants need
high concentration

↳ 17 hous night and 7
daylight