Biostimulants/agents include active substances and/or microorganisms that, when applied around plants or plant roots, can stimulate natural physiological processes in plants to enhance or benefit plant nutrient absorption, nutrient absorption efficiency, tolerance to abiotic stresses, and crop quality.
With the in-depth research on biostimulants, the widely accepted biostimulants are mainly divided into six categories: humic acid, amino acids, seaweed extracts, inorganic salts, chitin and its derivatives, microorganisms and their metabolites, and plant extracts.
Plant extracts include major biological macromolecules such as proteins, sugars, nucleic acids, and lipids, as well as stimulating metabolites such as sterols, flavonoids, and saponins.
Biostimulants extracted from plants have a natural affinity and high activity with plants, making them easier to absorb and transport by plants. They can quickly activate signal response and transduction pathways in plants, and regulate plant growth and development and stress resistance.