indoleacetic acid
Quick Summary
Indoleacetic acid (IAA) is a naturally occurring plant hormone, classified as an auxin. It is primarily known for regulating plant growth by stimulating cell elongation in stems. IAA also influences cell division, fruit development, root formation from cuttings, and leaf fall.12
This hormone affects plants by interacting with chemical bonds in plant cell walls, allowing cells to change irreversibly and absorb water. IAA plays a role in phototropism (growth toward light) and geotropism (growth against gravity) by influencing how auxin distributes on different sides of the plant stem and roots. While it promotes stem elongation, its effect on root growth is inhibitory, though not fully understood. Both natural and synthetic auxins are utilized in horticulture and agriculture for various purposes, including promoting rooting and controlling weeds.12
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angiospermTransport and plant growth…common of which is called indoleacetic acid. Auxins are formed in young, growing organs, such as opening buds, and are transported away from tips of shoots toward the base of the plant, where they stimulate the cells to elongate and sometimes to divide. Responses to gravity and light are also…
Read More…common of which is called indoleacetic acid. Auxins are formed in young, growing organs, such as opening buds, and are transported away from tips of shoots toward the base of the plant, where they stimulate the cells to elongate and sometimes to divide. Responses to gravity and light are also…
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hormoneAuxins…most important auxin is β-indolylacetic acid (IAA), which is formed either from the amino acid tryptophan or from the breakdown of carbohydrates known as glycosides. The hormone affects plants by its action on chemical bonds of carbohydrates comprising plant cell walls. The process permits the cells to be irreversibly…
Read More…most important auxin is β-indolylacetic acid (IAA), which is formed either from the amino acid tryptophan or from the breakdown of carbohydrates known as glycosides. The hormone affects plants by its action on chemical bonds of carbohydrates comprising plant cell walls. The process permits the cells to be irreversibly…
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