We all know that plants need light, water, oxygen and nutrition to grow and develop. All these qualify as extrinsic factors. While extrinsic factors are important, did you know that plant growth depends on intrinsic factors too? They can be intracellular genes or intercellular chemicals. These chemicals are called Plant Growth Regulators. Plant Growth Regulators are defined as small, simple chemicals produced naturally by plants to regulate their growth and development.

Characteristics: Plant Growth Regulators can be of a diverse chemical composition such as gases (ethylene), terpenes (gibberellic acid) or carotenoid derivates (abscisic acid). They are also referred to as plant growth substances, phytohormones or plant hormones. Based on their action, they are broadly classified as follows: Plant Growth Promoters – They promote cell division, cell enlargement, flowering, fruiting and seed formation.