Plant Growth and Development
- The effect of daily duration of light and dark hours on the growth and development of plants, especially flowering is called photoperiodism.
- On the basis of photoperiodic response to flowering, plants have been divided into the flowering categories such as, short day plants (SDP), long day plants (LDP), short - long day plants (S-LDP), Long - short day plants (L - SDP), Day neutral (or) indeterminate plants and Amphiphotoperiodic plants.
- SDP is also called as long night plants that undergoes dark period (or) scotoperiod If the plant is exposed to even a flash of light before achieving a critical dark period, flowering is inhibited and is called as night break reaction.
- Photo periodic response is mediated by phytochrome which shows reversible changes in red (660 nm) and far red (730 nm) wavelength.
- Long day plants require a high ratio of Pfr to Pr for flowering stimulus.
- Short day plants require a low Pfr to Pr ratio.
- The chemical inducing flowering has been named as florigen, which is not identified yet.
Watch this video for the topic Photoperiodism Part-1 from 0:20 to 7:55
Watch this video for the topic Photoperiodism Part-2 from 0:10 to 9:52
Disclaimer: Compete.etutor.co may from time to time provide links to third party Internet sites under their respective fair use policy and it may from time to time provide materials from such third parties on this website. These third party sites and any third party materials are provided for viewers convenience and for non-commercial educational purpose only. Compete does not operate or control in any respect any information, products or services available on these third party sites. Compete.etutor.co makes no representations whatsoever concerning the content of these sites and the fact that compete.etutor.co has provided a link to such sites is NOT an endorsement, authorization, sponsorship, or affiliation by compete.etutor.co with respect to such sites, its services, the products displayed, its owners, or its providers.