Product Name:

Paclobutrazol

CAS NO.:

76738-62-0

Product Introduction:

 Paclobutrazol (PP 333, PBZ) is a plant Growth Regulator (PGR). It acts by inhibiting gibberellin biosynthesis, reducing internodial growth to give stouter stems, increasing root growth, causing early fruitset and increasing seedset in plants such as tomato and pepper. Paclobutrazol (PP 333, PBZ) has also been shown to reduce frostsensitivity in plants.

Paclobutrazol (PP 333, PBZ) is also used to reduce shoot growth and has been shown to have additional positive effects on trees and shrubs. Among those are improved resistance to drought stress, darker green leaves, higher resistance against fungi and bacteria, and enhanced development of roots. 

Product formulations:

Paclobutrazol 95%, 15%/25%/30%/50% WP, 15%/25% SC

Solubility & Stability:

Solubility In water 22.9 mg/l. In xylene 5.67, n-heptane 0.199, acetone 72.4, ethyl acetate 45.1, n-octanol 29.4, methanol 115, 1,2-dichloroethane 51.9 (all in g/l). Stability Stable for more than 2 years at 20 °C, and more than 6 months at 50 °C. Stable to hydrolysis (pH 4–9), and not degraded by uv light (pH 7, 10 days).

Applications:

Biochemistry: Inhibits gibberellin biosynthesis by inhibition of the conversion of ent-kaurene to ent-kaurenoic acid, and inhibits sterol biosynthesis by inhibition of demethylation; hence inhibits the rate of cell division.

Mode of action: Plant growth regulator taken up into the xylem through the leaves, stems or roots, and translocated to growing sub-apical meristems. Produces more compact plants and enhances flowering and fruiting.

Uses: Used on fruit trees to inhibit vegetative growth and to improve fruit set; on pot-grown ornamentals and flower crops (e.g. chrysanthemums, begonias, freesias, poinsettias and bulbs) to inhibit growth; on rice to increase tillering, reduce lodging and increase yield; on turf to retard growth; and on grass seed crops and oilseed rape to reduce height and prevent lodging. To be applied as a foliar spray, as a soil drench, or by trunk injection. Has some fungicidal activity against mildew and rusts. Rates of application vary widely, depending on area of use, application method, application timing, size of crop, and cultivation method.

Phytotoxicity: Non-phytotoxic, though it intensifies greening. Some spotting has been noted on periwinkle foliage at higher temperatures.