IAA (indoleacetic acid) is a naturally occurring auxin, which can also be synthesized artificially. Its activity is low and it is the weakest hormone in auxin. It has little side effect on organ formation, is easy to be destroyed under high temperature and high pressure, is degraded by IAA decomposing enzymes in cells, and is easy to decompose when exposed to light.
NAA (naphthylacetic acid) is 3-4 times higher than IAA in tissue culture, and it is widely used because it can be synthesized in large quantities, resistant to high temperature and high pressure, and not easy to decompose and destroy. NAA and IBA are widely used for rooting and interact with cytokinin to promote bud proliferation and growth.
IBA (indolebutyric acid) is a growth regulator, which has a strong ability to promote hair roots.
2,4-D (2,4-dichlorophenoxyacetic acid) is 10 times higher than IAA, especially in promoting callus formation, but it strongly inhibits bud formation and affects organ development, and its suitable dosage range is narrow, and excessive dosage often has toxic effects. Tissue culture is often used in the primary culture stage of callus induction.
When preparing auxin, you can first use a small amount of 95% alcohol to help dissolve it. 2,4-drops can be dissolved with 0. 1mol/L NaOH or KOH. Auxin is often prepared into 1mg/ml mother liquor, which is stored in the refrigerator for later use.
The amount of growth regulator used is very small, and the concentration is generally expressed in mg/L. The concentration of growth regulator in tissue culture varies with plant species, parts, periods and endogenous hormones. Generally, the concentration of auxin is 0.05-5 mg/L, and the concentration of cytokinin is 0.05- 10 mg/L. ..