6-benzylaminopurine

Plant growth regulator

Stimulates the following effects: cell division; lateral bud emergence (apples, pears, oranges); basal shoot formation (roses, orchids); flowering (cyclamen, cacti); fruit set (grapes, oranges, melons); causes abscission of young fruitlets, leading to increased fruit size, stimulates flower bud formation and regular bearing in fruit trees. Inhibits senescence of rice seedlings. Enhances lateral bud break and lateral shoot growth, leading to fuller white pine trees. Also causes uniform bolting and increased seed production in spinach. Applied by foliar application, soaking, or painting. Its limited ability to translocate is utilised to restrict effects to the target part of the plant, by local application. Applied at 30 g/a for apple trees.

Oral:Acute oral LD₅₀ for male rats 2125, female rats 2130, mice 1300 mg/kg. Percutaneous:Acute percutaneous LD₅₀ for rats >5000 mg/kg. Not a skin or eye irritant (rabbits); not a skin sensitiser. ADI:0.05 mg/kg.

Ecotoxicology:
Algae: EC₅₀ (96 h) 363.1 mg/l ('Paturyl' 10 SL formulation).Bees: LD₅₀ (oral) 400 μg/bee, (contact) 57.8 l/ (both 'Paturyl' 10 SL formulation).Birds:Practically non-toxic.Daphnia: LC₅₀ (24 h) for D. carinata >40 mg/l.Fish: LC₅₀ (48 h) for carp >40 mg/l.
Environmental fate:
Animals:Almost all of administered ¹⁴C was excreted in urine and faeces. Three metabolites were identified.Soil:16 Days after application to soil at 22℃, 6-benzylaminopurine had degraded to 5.3% (sandy loam) and 7.85% (clay loam soil) of applied dose. Other studies indicate DT₅₀ 7-9 w.Plant:More than 9 metabolites were identified from metabolism studies in soya beans, grapes, maize and cocklebur. Urea is an end product.