Plant Growth Regulators in morden agriculture

Any substance or mixture of substances intended, through physiological action, for accelerating or retarding the rate of growth or maturation or for otherwise altering the behavior of ornamental or crop plants or the produce thereof, but not including substances intended as plant nutrients, trace elements, nutritional chemicals, plant inoculants, or soil amendments.

The use of plant growth regulators in morden agricultural production began in the 1930s. The first discovery and use of plant growth regulators was with acetylene and ethylene, which enhanced flower production in pineapple. Subsequently, use of plant growth regulators has grown exponentially to become a major component of agricultural commodity production.

Certain herbicides and insecticides that are not true plant growth regulators cause some plant-growth-regulating effects. For example, the widely used insecticide carbaryl is used to thin apple fruit from trees and to aid in encouraging annual bearing.

Active ingredient Registered crops and functions
Ancymidol Ornamental plants – growth inhibitor
Butralin Tobacco – shoot inhibitor
Alcohols Tobacco – shoot inhibitor
Chlormequat chloride Ornamental flowers – shoot inhibitor
Cytokinin Ornamental plants, vegetables, fruits including citrus – hasten maturity, enhance fruit color, growth enhancer, enhance tuber color, improve tuber quality
Daminozide Ornamental plants – growth inhibitor
Ethephon Turfgrass – reduces mowing frequency Various fruits, vegetables, and nuts – hastens ripening and maturity, enhance fruit color and floral stimulant Cucurbits – increases flowering Ground covers – inhibits flowering Ornamental trees – inhibits fruiting Tobacco and cotton – hastens maturity Cereal grains and grasses grown for seed – reduces lodging
Flurprimidol Ornamental woody plants and ground covers – reduces pruning Turfgrass – reduces mowing frequentcy
Gibberellic acid Small fruits, cucurbits – increase fruit set Citrus – promote rind/peel integrity, prevent fruit drop Rice, cotton – growth enhancer
Gibberellin mixtures Cut flowers – plant preservative Tree fruit – increase fruit size, hasten maturity, shoot stimulant Evergreen trees – floral stimulant, stimulate germination
Indole-3-butyric acid (IBA) Ornamental plants and trees – root stimulant
Maleic hydrazide, potassium salt Tobacco – shoot inhibitor Stored bulbs – sprout inhibitor
Mefluidide Ground covers, shrubs, ornamental trees – reduces pruning Turfgrass – reduces mowing frequency
Mepiquat chloride Cotton - growth inhibitor, enhance uniform fruit maturity
Mepiquat pentaborate Cotton – growth inhibitor, enhance uniform fruit maturity
Naphthalene-acetic acid (NAA) Ornamental plants – stimulates rooting, increase vegetative growth
1-Naphthaleneacetamide (NAD) Woody ornamental cuttings – rooting stimulant
n-Decanol Tobacco – shoot inhibitor
Paclobutrazol Ornamental flowers – promotes uniform flowering Ornamental plants – reduces internodal length Ornamental trees – growth inhibitor Turfgrass – increased plant thickness, growth inhibitor
Prohexadione calcium Peanut, Tree fruit, turfgrass grown for seed – growth inhibitor, reduce vegetative growth
Trinexapac-ethyl Turfgrass – reduces mowing frequency
Uniconazole Ornamental plants – growth inhibitor