Hint: Plants also have hormones like humans which help them in their growth and development. Some will enhance/trigger the shooting –rooting while some inhibit them. Some of them are used in plant tissue culture. These all are the chemical or chemically modified proteins.
Complete answer: IAA- Indole acetic acid: It is one of the most commonly found hormones in the plants in the auxin class. It is the derivative of the indole with a carboxymethyl substituent. It is soluble in ethanol. It appears to be white. It has the major function of elongation of the plants and their development. Zinc is the important micronutrient essential for the working of the IAA. NAA- Naphthalene acetic acid: It is an organic compound. It is colourless, soluble in organic solvents. It has naphthalene on the ‘1 position’ of its carboxymethyl. It is an auxin which initiates the rooting process. It is also useful in plant tissue culture. It is found in various rooting horticulture products. IBA- Indole butyric acid: It also belongs to the auxin family with the real name indole-3-butyric acid. It is white yellow crystalline in colour. It was first called the synthetic auxin. It is important in inducing adventitious roots in stem cuttings. It is a rooting hormone acting as a root stimulant.
Note: All three have a major effect on the morphological features of the plant rather than just shooting or rooting. IAA being the natural auxin is present in abundance in plants but NAA is the synthetically made auxin in the labs, which is similar to the IAA. The anti-auxin used is PCIB (p- chlorophenoxy isobutyric acid). TIBA (triiodobenzoic acid) is the inhibitor which will obstruct the transport of auxin.