Write differences between auxins, gibberellins, cytokinins, abscisic acid and steroids.
These are the various phytohormones produced by a plant body. The main difference lies in the functions of these phytohormones :
Auxin: Helps in stem and root elongation, maintenance of apical dominance and various tropisms, involved in differentiation of vascular tissue, prevention of abscission, stimulation of the release of ethylene, enhancement of fruit development.
Gibberellins: Helps in cell division, initiate mobilization of storage materials in seeds during germination,promotes stem elongation, breaking of seed dormancy, stimulate bolting in biennials, stimulates growth of pollen tube.
Cytokinins: Promote and affect cell division, delays senescence, activation of dormant buds.
Abscisic Acid: Growth inhibitor, brings about fruit ripening, maintains dormancy in seeds and buds, stimulates the closing of stomata.
Plant steroids : It includes steroid alkaloids, phtosterols and brassinolides.
Brassinolides are involved in the light-induced expression of genes.
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