what are phytochromes and what or which plant developmentphy

what are phytochromes and what or which plant development/physiological phenomena are controlled by them?

Solution

Phytochromes are the light sensitive pigments present in some of the bacteria, fungi and plants. These photoreceptor pigments are sensitive to red and far-red light region. The detection of light helps to sense the length of day light and nights, which is necessary for the regulation of flowering time and circadian rhythms. Phytochromes also play a key role in seed germination, seedling size, shape, chlorophyll synthesis, number of leaves, etc.