An artificial method to induce flowering in plants - vernalisation

 

The process by which juvenile or vegetative phase is reduced and enhances the process of flowering with the cold treatment. By vernalisation the cold varieties of various plants are transformed into spring or summer varieties.

The place of plants where vernalisation may occur are all meristematic tissue like shoot tip, embryo tip etc. The low-temperature stimulus is perceived by the shoot apex of a mature stem or embryo of the seed. The metabolically active apical meristem is the site for vernalisation. Young leaves are more receptive to vernalisation.

The phenomenon  which induces the process of  the flowering  on a low-temperature  is called Vernalisation.

Photoperiodism is the primary process in flowering and the  Vernalisation is the secondary process of flowering.

To understand the process of vernalisation,The detail must know about the two kinds of variety. These are Spring varieties and winter varieties 

The spring varieties are grown  in spring and generally come to flower and produce grain before the same growing season. 

The winter varieties are planted in the autumn season. If they are planted in spring, they will not flower to produce grains.

Factors needed for the  Vernalisation

 An appropriate amount of  humidity in the environment and moisture in plant parts is necessary to the stimulus for vernalisation.

Vernalisation cannot take place in dry and descicated parts of plants .The  vernalisation can occur  only in actively dividing cells. Therefore  an active embryo and  the shoot apical meristem is the  site for vernalisation.

Proper nutrition  is  also required for vernalisation to occur because it occurs in the actively dividing cells and thus  cells .

The low temperature required for vernalisation treatment is between 1∘C–10∘C. The effect of vernalisation can be  reversed by providing  the  high temperature to plants. This  is called Devernalisation.  The duration of treatment varies from a few hours to a few days depending on the plant species.

According to  Melchess, a  hormone called  Vernalin is produced during the low-temperature treatment.

The stimulus is received by the dividing cells of the shoot, The vernalin hormone induces a physiological change in the plant that induces flowering.

Advantages of Vernalisation It also induces the  early flowering. Due to the induction of flowering, The winter variety crops can be converted to spring variety. The tropical plants can be grown in temperate areas where they do not grow in most cases.

It increases the yield of plants and helps to develop the power to withstand the cold or frost and also increase the resistance for the Various types of fungal diseases.