Which of the following plant hormones regulates growth, particularly by stimulating cell elongation in stems?

🔑Key Points:
-Stem Elongation
-Stem elongation refers to the rapid growth in the length of the internodes of the upper stem before the reproductive phase starts for the plant.
-Stem elongation causes many problems for the plant, such as skinny stems that are too weak to support large flowers, as well as plants that grow too high vertically and appear spindly, so it should be prevented.
-Auxin
-Auxin is a group of plant hormones that regulate growth, particularly by stimulating cell elongation in stems.
-Auxins also play a role in cell division and differentiation, in fruit development, in the formation of roots from cuttings, in the inhibition of lateral branching and in leaf fall.
-The most important naturally occurring auxin is ß- indolyl acetic acid (IAA).

🔴Additional Information:
-Ethylene
-Ethylene is the first-identified plant hormone known to regulate numerous processes in plant growth, development, and response to biotic and abiotic stresses.
-Ethylene is best known for its effect on fruit ripening and thus has great commercial importance in agriculture.
-Gibberellin
-Gibberellin is a group of plant hormones that occur in seeds, young leaves, and roots.
-It stimulates the growth of main stems, especially when applied to the whole plant.
-It is commercially obtained from fungi.
-Cytokinin
-Cytokinins are plant hormones that influence not only numerous aspects of plant growth, development and physiology, including cell division.
-Cytokinins are also produced by other prokaryotic and eukaryotic organisms such as bacteria, fungi, microalgae and insects.