A lot of people are interested in the process that flowering plants normally go through. One of the most important things is the succession of the exposure of flowering plants to light and dark cycles. Take note that this should be done for a certain period.
For example, if flowering plants would be exposed only to long nights, then they will not flower properly. The flowering process is also not as effective when they are only exposed to a short amount of light during a certain part of the day. Other things that can disrupt the flowering process in plants is the photoperiod, the availability of the needed nutrients, temperature, and so much more.
The correct answer to this question is PR. Ultimately, the Pr light is converted by the red light to Pfr. This conversion then acts as the promoter of flowering. Photoperiodism is an important process to flowering because it gives every plant the classification of either being a long day species or a short day species.
The word photoperiodism is defined as the length of time that each plant needs in the sun so that it can bloom, grow, and change color. For plants that need a long time in the sun, they would be referred to as a long day species. Plants that do not need as much time would be called a short-day species.
A plant that is a long day plant or a long day species is a plant that requires more time in the sun. This time in the sun is needed so that the plant can change its color, grow, and bloom.
.These plants often grow in the summer. They differ from short-day plants, as short-day plants do better in darkness and do not require as much time in the sun.
When it comes to the aspect that controls the flowering process in long-day plants, that would be PR. The Pr light is converted to Pfr by a red light.
What usually controls the flowering process of long-day plants is the conversion of Pr to Pfr by the red light from the sunlight. What controls the growth of most flowering plants is their exposure to red light from the sunlight.
The exposure of flowering plants to red light causes the chromoprotein to become active and functional. The active form of chromoprotein that comes due to the exposure of flowering plants to red light from sunlight causes flowering plants to grow. What this means is that plants that are not exposed to direct sunlight and those in the shade will experience slow growth.
The reason is that they are not getting Pfr that will trigger them to grow like other flowering plants that are growing in the sunlight. To have a better understanding of this, you need to understand the term photoperiodism. This refers to the responses of flowering plants to lengths of dark and light periods during their developmental stages.
In long-day plants, the flowering process is dictated by Pr, which changes into a red light and acts as the provocation of flowering. The timing of the flowering is determined by endogenous genetic factors as well as various other variables.
The genetic and molecular processes that rule this activity have been analyzed in the long-day flowering plants. One of the extremely important factors which regulate the flowering response to a succession of light/dark cycles is the length of the continuous dark period.
During dark periods, a level of Pfr is formed by thermal reversion of Pfr to Pr, which no longer prevents flowering in short-day plants and is too low to stimulate flowering in long-day plants. It has generally been determined from such experiments that Pfr of photochromic is necessary to flow in short-day plants.
M. Porter, Senior Executive, Master of Art, San Jose
Answered Dec 14, 2018
The flowering process in long day plants is controlled by Pr which is converted by red light to Pfr which then acts as a promoter of flowering. The detail which gives each plant their classification as being a short day or a long day species is the photoperiodism of each plant.
Photoperiodism means the length of time needed in the sun for the plant to grow, change color, or bloom. If a plant needs a lot of sun they are considered a long day plant where a plant which needs very little sunlight and thrives better with more darkness is called a short day (or a long night) plant.
Many plants which flower in the autumn or spring are usually short day plants. This is because the days are shorter in the fall and the spring time is usually very wet and rainy which means there is a limited amount of sun during that time.