Gibberellins, a major group of naturally occurring plant hormones, are diterpenoid acids, known to influence a range of plant developmental processes including stem elongation, germination, dormancy, flowering, sex expression, enzyme induction, fruit size and quality, and leaf and fruit senescence. Gibberellins are commercially produced by fermentation of natural fungus, Gibberella fujikuroi. The most commonly used Gibberellic acid, GA3, is primarily formulated as solutions (2 to 5 % in isopropyl alcohol, 10 % in methyl alcohol), as 5 to 20 % wettable or soluble powders, or both, as 3.1 % soluble granules or as 1 to 10-g effervescent tablets. The other frequently used gibberellins, GA4+7, are primarily formulated as 1 to 4 % solutions either in tetrahydrofurfuryl alcohol (THFA) or in propylene glycol. Of the solvents currently used, isopropyl alcohol and methyl alcohol offer severe disadvantages such as flammability, toxicity, and restrictions in manufacturing, packaging, labeling, transportation, and warehousing. The THFA used in some of the formulations is considered corrosive to the eye and skin. Low solubility of gibberellins in propylene glycol does not permit solution formulations with greater than 2 % wt/wt gibberellins. The powder formulations are not user friendly and require quite a long time to achieve true solubility of the active component in tank mixes. Due to low solubility and undesirable hydrolysis, it has not been possible to formulate gibberellins in aqueous systems. This paper will present formulation studies leading to the development of stable, high potency (GA3 at 40 % wt/wt and higher; GA4+7 at 10 % wt/wt and higher), dust free, instantly water wettable, dispersible, and soluble Gibberellin plant growth regulator granular formulations by low pressure extrusion methodology. Field biological efficacy studies on grapes showed concentrated water soluble granular formulation either equivalent or superior to the standard powder formulation.
Domestic orders are delivered via United Parcel Service (UPS) or United States Postal Service (USPS). Transit
times average 3 to 5 business days. Please be aware that UPS will not deliver packages to Post Office Boxes.
International orders are delivered via courier post services which can be either a postal service, courier
service, or a combination of both. Standard Service is untraceable. Please allow 4-7 weeks for delivery.
Please be aware that carriers will not deliver packages to Post Office Boxes. Because of the variability of
customs processes and procedures in different countries, ASTM International cannot guarantee transit times to
international destinations. Customs duty and taxes are the responsibility of the consignee.
Shipping & Handling charges follow the rate schedule, below:
Order Total
Shipping & Handling Fee (US Domestic)
Up to $50.00
$18.72
$50.01 to $100.00
$20.80
$100.01 to $150.00
$29.52
$150.01 to $250.00
$39.09
$250.01 to $500.00
$56.25
$500.01 to $750.00
$76.42
$750.01 to $1000.00
$93.15
$1000.01 to $1500.00
$121.27
$1500.01 to $2500.00
$158.38
$2500.01 to $4999.00
$209.04
$5000.00 to higher
FREE
Order Total
Shipping & Handling Fee (International)
Up to $50.00
$68.72
$50.01 to $100.00
$70.80
$100.01 to $150.00
$79.52
$150.01 to $250.00
$89.09
$250.01 to $500.00
$106.25
$500.01 to $750.00
$126.42
$750.01 to $1000.00
$143.15
$1000.01 to $1500.00
$171.27
$1500.01 to $2500.00
$208.38
$2500.01 to $4999.00
$259.04
$5000.00 to higher
FREE
Shipping and Handling charges are approximate. Additional charges may be incurred if your order requires multiple shipments. This does not apply to complete sets and sections.