1. They occur widely in the drugs, herbicides, plant growth regulators , and dyestuffs. 2. It is used as a plant growth regulator to stimulate ethylene production. 3. It functions as a plant growth regulator against the plant hormone auxin. 4. "' Chlormequat "'is an organic compound that is used as a plant growth regulator . 5. Plant hormones act as plant growth regulators or modulators. 6. These culture media are free of plant growth regulators ( Silva et al ., 2014 ). 7. "' 1-Methylcyclopropene "'( 1-MCP ) is a cyclopropene derivative used as a synthetic plant growth regulator . 8. However, more recent research suggests that wood fibre can have detrimental affects on " plant growth regulators ". 9. His work with plant growth regulators had significant practical consequences in the fields of forestry, agriculture, and horticulture. 10. Plant hormones, known as plant growth regulators ( PGRs ) or phytohormones, are chemicals that regulate a plant's growth.