Gibberellic Acid (GA3)
Synonyms: (3S,3aR,4S,4aS,7S,9aR,9bR,12S)-7,12-dihydroxy-3-methyl-6-methylene-2-oxoperhydro-4a,7-methano-9b,3-propenoazuleno[1,2-b]furan-4-carboxylic acid (IUPAC); Gibberellin A3; GA3; 'Activol' (Valent BioSciences); 'Berelex' (Syngenta, Valent BioSciences); 'Ceku-Gib' (Cequisa); 'GA-Sun' (Sundat); 'Giberoc' (Rocca); 'Kri-Gibb' (Krishi Rasayan); 'Laikuaj' (Lainco); 'Release' (Valent BioSciences); 'RyzUp' (Valent BioSciences); 'Trikor' (Hermoo); 'Vimogreen' (Vipesco); mixtures 'PGR-IV' (+ 4-indol-3-ylbutyric acid) (Marman). Other products 'Agro-Gibb' (AgroSan); 'Falgro' (Fine); 'Fitogib' (Agrimix); 'Genial GA3' (Chimiberg); 'Giberluq' (LUQSA); 'GibGro' (Nufarm Americas); 'Gibrel' (Valent BioSciences); 'Gibrelin' (Gobbi); 'Gi-Tre' (Agrimport); 'Grocel' (Valent BioSciences); 'Hek-Gibb' (Hekta351); 'Megagibb' (Doğal); 'Nectar' (Agrimport); 'N-Large' (Stoller); 'Novagib' (de Sangosse, Fine); 'Ormone Ag Compresse' (Sipcam S.p.A.); 'PGR-IV Plus' (with Bacillus cereus, strain BP01) (Helena); 'Pol-Gibrescol' (Ciech); 'Pro-Gibb' (Valent BioSciences); 'Ralex' (Valent BioSciences); 'Supagibb' (Plaaskem S.A.); mixtures 'Fengib' (+ MCPA-thioethyl) (Sipcam Inagra); 'Green Sol 48' (+ kinetin) (Frit); 'Laiteca' (+ 1-naphthylacetic acid + 2,4-D) (Lainco); 'Profile' (+ 6-benzylaminopurine) (Agrimport). Discontinued products 'GIB' * (Burlington); 'Gibbex' * (Griffin); 'Point Acigib' * (Point Enterprise); 'Rasayanic Acid' * (Krishi Rasayan); 'Ro-Gibb' * (Rotam); 'Strong' * (Hubei Sanonda); 'Uvex' * (Productos OSA); mixtures 'Boll-Set' * (+ 4-indol-3-ylbutyric acid) (Micro Flo); 'Early Harvest' * (+ 4-indol-3-ylbutyric acid + cytokinins) (Griffin); 'Fengib' * (+ MCPA-thioethyl) (Hokko); 'Maxon II' * (+ 4-indol-3-ylbutyric acid) (Agriliance); 'Mepex Plus-CP' * (+ 4-indol-3-ylbutyric acid + cytokinins + mepiquat chloride) (DuPont); 'Super Lagniappe' * (+ 4-indol-3-ylbutyric acid + cytokinins) (Agriliance); 'Zero-One' * (+ MCPA-thioethyl) (Hokko).
CAS No.: 77-06-5
Molecular Weight: 346.38
Molecular Formula: C19H22O6
m.p.: 223–225 °C (decomp.)
Form: Crystalline solid.
Solubility: In water 4.6 mg/ml (room temperature). Soluble in methanol, ethanol, acetone, and aqueous alkalis; slightly soluble in diethyl ether and ethyl acetate. Insoluble in chloroform. Potassium, sodium, and ammonium salts: Readily soluble in water (potassium salt 50 g/l).
Stability: Dry gibberellic acid is stable at room temperature, but slowly undergoes hydrolysis in aqueous or aqueous-alcoholic solutions, DT50 (20 °C) c. 14 d (pH 3–4), 14 d (pH 7). In alkalis, undergoes a rearrangement to less biologically-active compounds. Decomposed by heat.
Gibberellic acid GA3 acts as a plant growth regulator on account of its physiological and morphological effects in extremely low concentrations. Translocated. Generally affects only the plant parts above the soil surface. Has a variety of applications, e.g. to improve fruit setting of clementines and pears (especially William pears); to loosen and elongate clusters and increase berry size in grapes; to control fruit maturity by delaying development of the yellow colour in lemons; to reduce rind stain and retard rind ageing in navel oranges; to counteract the effects of cherry yellows virus diseases in sour cherries; to produce uniform seedling growth in rice; to promote elongation of winter celery crop; to induce uniform bolting and increase seed production in lettuce for seed; to break dormancy and stimulate sprouting in seed potatoes; to extend the picking season by hastening maturity in artichokes; to increase the yield in forced rhubarb; to increase the malting quality of barley; to produce brighter-coloured, firmer fruit, and to increase the size of sweet cherries; to increase yields and aid harvesting of hops; to reduce internal browning and increase yields of Italian prunes; to increase fruit set and yields of tangelos and tangerines; to improve fruit setting in blueberries; to advance flowering and increase the yield of strawberries; and also a variety of applications on ornamentals. Application rates up to 80 g/a per application, depending on desired effect.
80%, 85%, 90%, 93%, 95% TC
4%, 6% EC
10%, 16%, 20% ST (water soluble tablet)
10%, 20% SP
Aluminum jars; drums; foil bags
Risks and Safety Information
Gibberellic acid GA3 is not regulated by UN as hazardous substance.
Acute oral LD50 for rats and mice >15 000 mg/kg. Skin and eye Acute percutaneous LD50 for rats >2000 mg/kg. Non-irritating to skin and eyes. Birds Acute oral LD50 for bobwhite quail >2250 mg/kg. Fish LC50 (96 h) for rainbow trout >210 ppm. Daphnia EC50 (48 h) 488 mg/l; NOEL (48 h) 360 ppm.