Question

Describe various plant hormones with their functions.

Answer 1

The various plant hormones are:

• Auxin: It is synthesised in the plant shoot tips, developing embryos, flowers and seeds. It promotes the growth of adventitious roots and fruits, helps inhibit abscission and controls ageing and senescence.
• Cytokinin: They are found in sites where cell division occurs actively, such as in root tips, seeds, fruits and leaves. They work along with auxins to promote cell division and they also help delay senescence.
• Gibberellin: It is synthesised mainly in the developing regions of the stem and in seeds. It stimulates cell division and cell elongation in these regions.
• Abscisic acid: It is present mostly in developing seeds where it promotes abscission and inhibits growth. It also helps promote closing of stomata in leaves under water stress conditions.
• Ethylene: It is produced mainly in the plant roots, ripening fruits, and the apical meristem of shoots. It helps stimulate the ripening of fruits and also initiates abscission in the fruits and leaves.