Why Is Paclobutrazol a Go-To Growth Regulator for Compact, High-Yield Crops?

Technical Introduction

Paclobutrazol (C₁₅H₂₀ClN₃O, CAS No. 76738-62-0) is a triazole-class plant growth regulator (PGR) widely used to control plant height, promote compact growth, and improve flowering and fruit set.
It functions by inhibiting gibberellin biosynthesis, a natural plant hormone responsible for stem elongation.
Paclobutrazol is absorbed primarily through the roots (soil application) or foliage (foliar spray) and has systemic action, moving through the xylem to growing points.

Its residual activity in soil makes it effective for long-term growth regulation, especially in fruit trees and ornamentals.

Applications

1. Agriculture

• Height Control: Prevents excessive vegetative growth in crops like wheat, rice, and maize.

• Lodging Reduction: Strengthens stems to reduce crop losses from wind and rain.

• Yield Improvement: Improves flowering uniformity and fruit set in mangoes, apples, and grapes.

2. Horticulture & Landscaping

• Produces more compact, aesthetically appealing ornamental plants.

• Reduces pruning frequency in shrubs and trees.

3. Turf Management

• Slows grass growth to reduce mowing frequency and improve turf density.

Advantages

• Long-Lasting Effect: One application can regulate growth for weeks or months.

• Multiple Application Methods: Can be applied via foliar spray, soil drench, or trunk injection.

• Improves Stress Tolerance: Enhances drought and disease resistance by shifting plant energy from shoot growth to root and defense systems.

Typical Parameters

FAQs

Q1: Is paclobutrazol safe for all crops?
A1: No—some crops are sensitive. It is essential to follow label recommendations for species-specific doses.

Q2: How long does it stay active in soil?
A2: It can persist for months, depending on soil type, organic matter, and climate conditions.

Q3: Can paclobutrazol be tank-mixed with fertilizers or pesticides?
A3: Often yes, but compatibility tests are recommended before large-scale use.

Q4: Does it affect flowering?
A4: Yes—it can advance or synchronize flowering in certain fruit trees, leading to improved yields.

Q5: Is paclobutrazol environmentally safe?
A5: It is stable in soil and has low volatility, but excessive use may impact non-target plants due to persistence.