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.