As the name says, Photoperiodism is the physiological response of a plant development with the respect to the relative lengths of day or night time or light and dark periods. The significance of photoperiodism is in the induction of flowering. On the other hand, Vernalization also prompts the flowering in the plants but by getting them into a prolonged cold period, this exposure to the cold temperature for a long time helps in the reduction of the vegetative growth stage of the plants.
Photoperiodism and Vernalization are the mechanisms involved in induction of flowers in plants (directly or indirectly), that can be performed artificially as well as naturally. Moreover, these process requires plant hormones for their assistance and have natural importance in too in agriculture field.
This article will further differentiate the two environmental conditions of a plant and other key factors.
Table of Contents
Photoperiodism in Brief
The physiological response of the plants with respect to the length of day or night is known as the Photoperiodism. It mainly triggers or supports the flowering in the plants, with the help of hormone. In this process the vegetative buds are been converted into the flowering buds during the photoperiods.
The photoperiods can be dark or light periods, and plants have the capability to sense the photoperiods specially the night length, which is performed with the help of photoreceptor proteins such as cryptochrome’s or phytochromes found in leaves. On the basis of the response developed by the plants, they are been categorized as the short-day plants, long-day plants, and day-neutral plants.
Vernalization in Brief
The term “vernalization” has been derived from the word “vernus” which is a Latin word and is referred to as “of spring“. Therefore, vernalization can be describe as the phenomenon, that is performed with the aim of increasing the production of crops by exposing them to grow for longer periods especially the cold winter temperature or other same situations.
As a result the plant develop the potential to bloom, with the time the process is completed during their development. Although, it may take some time by the plant to prepare themselves for further flowering.
This process is usually performed in the place where the natural growth of that particular plant is not possible. Vernalization also benefits the plant breeding.
Difference Between Photoperiodism and Vernalization
Photoperiodism works with respect to light ( light and dark periods) in plants and animals and is responsible for the over all growth and development and other responses.
Vernalization is the process used by plants that works when plant are exposed to the cold temperature for certain duration and therfore preparing the plant for flowering by perceiving the flowering stimuli .
Role
Photoperiodism prepare the plants for flowering and stimuli as well.
Vernalization triggers the plants to gear up the ability of flowering, however it does not directly support in induction of flowering.
Stimuli receiving parts
In case of photoperiodism the stimuli provided by the light is only received by only leaves of a plant.
In veranlization the stimuli provided through the cold treatment are received by the meristem, leaves and embryos.
Hormone
The hypothetical hormone ‘Florigen’ is responsible for the mediating the photoperiodism in plants.
The hypothetical hormone ‘Vernalin’ that triggers the synthesis of florigen is responsible for the mediating the process of veranlization in plants.
Gibberellic Acid (GA) works for long-day plants only by replacing them to the exposure for long photoperiods.
Gibberellic Acid (GA) works for all plants and thus replace cold treatments to process with vernalization.
Time taken for flowering
The disclosure or openness of about 2 to 3 photoperiods is sufficient for inducing the flowers in plants.
The disclosure or openness to low temperature varying from -2 degree Celsius to 12 degree Celsius for about 50 days is needed to prepare the plant for flowering.
Reversible/Irreversible
Photoperiodism is an irreversible or cannot be reverted during unfavorable photoperiods and is interrupted by dark periods.
Vernalization can be reverted by the process known as devernalization, in which the plants are exposed to the high temperature (40 degree Celsius).
Transmission
The photoperiodic effect can be transmitted through grafting method to other plants.
The vernalization stimulus is not transferrable to other plants by any method.
Grafting Method
Photoperiodic stimulus is transferrable to other plants by the grafting method, but this is not applicable in vernalization stimulus.
Quick Comparison: Photoperiodism Vs Vernalization
| Photoperiodism | Vernalization |
|---|---|
| Photoperiodism is the respsonse with respect to length of light ( light and dark periods) in plants and animals and is responsible for the over all growth and development and other responses. | Vernalization is the chilling treatment given to plants for the accelerating and preparing them to flower. |
| Photoperiodism prepare the plants for flowering and stimuli as well. | Vernalization triggers the plants to gear up the ability of flowering, however it does not directly support in induction of flowering. |
| Stimuli receiving parts in photoperiodism are the mature leaves of a plant. | In veranlization the stimulus is percieved by the active meristem, leaves and embryos. |
| The hormone name 'Florigen' is responsible for the mediating the photoperiodism in plants. | The hormone 'Vernalin' that mediates the process of veranlization in plants. |
| Time taken for flowering is of about 2 to 3 photoperiods only on plants.is sufficient for inducing the flowers in plants. | The exposure to low temperature varies from -2 degree Celsius to 12 degree Celsius for about 50 days is needed. |
| Photoperiodism is an irreversible and its effects cannot be reverted. | Vernalization can be reverted by the process known as devernalization, where the plants are treated with the high temperature (40 degree Celsius). |
Bottom Line
Additionally, there are few similarities between Photoperiodism and Vernalization , such as both are mediated by the plant hormones, play crucial role in regulation of flowering and are important in agricultural practices. However, after knowing the exact uses of both the processes, one can apply accordingly and as per the need, but under the expert advise, which will be fruitful.
