They are all plant growth promoters - so what makes triacontanol different?

Last week, we introduced many application scenarios of triacontanol as a plant growth promoter. You can review it here:https://www.kelewell.de/en/post/triacontanol-from-beeswax-to-biotechnology-the-science-of-natural-growth-stimulation

Today, several plant growth promoters are commonly used on the market, such as triacontanol, brassinolide, sodium nitrophenolate, and DA-6 (diethyl aminoethyl hexanoate). All of them help promote plant growth — but how exactly do they differ?

1. Mechanisms

(1) Triacontanol

Triacontanol mainly enhances the activity of various enzymes such as polyphenol oxidase, improves cell membrane permeability, increases chlorophyll content, and strengthens photosynthesis and assimilation. It is especially effective at boosting the efficacy of other mixed formulations, making it an excellent synergistic regulator.

(2) Brassinolide

Brassinolide is an endogenous plant hormone, naturally produced within the plant. It acts directly on crops by balancing or supplementing internal hormones—for example:

• Promoting growth (auxin-like),

• Promoting flowering (similar to gibberellin + cytokinin),

• Promoting fruit enlargement (cytokinin + ethylene).

(3) Sodium nitrophenolate

This compound is a cell activator. It enhances cytoplasmic fluidity and promotes cell division, increases chlorophyll content, and accelerates metabolic processes. However, it is not naturally present in plants, so its effect is indirect.

(4) DA-6

DA-6 is not a natural plant hormone.Its mechanism relies on regulating the plant’s internal hormone balance. It increases the activity of peroxidase and nitrate reductase, helping the plant synthesize nutrients more efficiently. More enzyme activity = more nutrients. It also regulates water balance, improving cold, drought, and stress resistance while delaying senescence.Among these regulators, DA-6 contributes most to improving crop quality and yield.

2. Temperature

(1) Triacontanol

Works best between 20–25°C.Avoid using it under low temperatures, high temperatures, heavy rain, or strong winds.

• High temperature → use brassinolide

• Moderate temperature → triacontanol

• Low temperature → DA-6

(2) Sodium nitrophenolate

• Minimum effective temperature: 15°C

• Stronger effect above 25°C, visible within 2 days

• At 30°C, results appear within 24 hours

  It is strongly temperature-dependent — the higher the temperature, the stronger the activity.

(3) DA-6

As long as the plant is alive and there is temperature, DA-6 can work.It is suitable for low-temperature environments, making it widely used in winter greenhouses and early spring crops such as watermelon and strawberries.

(4) Brassinolide

As an endogenous hormone, it works as long as the plant can tolerate the temperature.

• Effective from 20°C upward

• The higher the temperature, the faster the response

• At low temperatures, its effect is weaker

  Above 30°C, concentration must be carefully controlled to avoid toxicity.

3. Duration

Triacontanol

Also known as beeswax alcohol, it is natural and reacts extremely fast.

• Corn seedlings show increased dry matter within 10 minutes

• Rice seedlings show increased reducing sugars and amino acids within 4 minutes

  Its effect on chlorophyll is stronger than brassinolide, though brassinolide maintains higher chlorophyll levels for longer.

Brassinolide

Acts the fastest, but duration is short: 10–15 days.Propionyl-brassinolide lasts 15–30 days, but has low utilization.

Sodium nitrophenolate

Takes 2–3 days to show effect.Duration: around 25 days.

DA-6

Part is used, part is stored, and it releases slowly.Duration: about 30 days, the longest among the four.

4. Different Abilities to Enhance Photosynthesis

Triacontanol, DA-6, and sodium nitrophenolate all strongly enhance photosynthesis:

• Triacontanol: promotes protein synthesis under both light and dark conditions

• DA-6: increases chlorophyll and enzyme activity

• Sodium nitrophenolate: boosts chlorophyll content and cell activity

• Brassinolide: weakest photosynthesis enhancer among the four

For greenhouses or prolonged cloudy/rainy weather, triacontanol, DA-6, and sodium nitrophenolate are better options than brassinolide.

5. Different Abilities to Improve Stress Resistance

• DA-6 → the strongest overall stress-resistance enhancer

• Sodium nitrophenolate → second, and very strong in nutrient uptake improvement

• Triacontanol → very good for improving fertilizer and pesticide efficiency

• Brassinolide → relatively weaker in stress resistance

Therefore, the choice should depend on crop type, temperature, and required physiological response. Using the wrong one may lead to significantly reduced effectiveness.

6. Production Processes & Yield Effects

Triacontanol has the best yield-enhancing effect because it directly promotes:

• The TCA cycle

• Glycolysis enzyme reactions

• Accumulation of photosynthates

• Transport of nutrients to seeds and fruits

Brassinolide, sodium nitrophenolate, and DA-6 work more indirectly, by activating physiological processes.

However:

• These three have mature industrial production.

• Triacontanol requires high-purity production, as impurities such as octacosanol (C28 alcohol) actually inhibit its effects.

• When purity reaches 99.79%, its performance increases significantly.

• PVC containers should be avoided, as their phthalate plasticizers and octacosanol can weaken the biological effects of triacontanol.

Conclusion

Each growth promoter has a different mechanism and physiological pathway. Their functions are not interchangeable.Therefore, selecting the right one requires considering temperature, crop needs, stress conditions, and desired outcomes.

Use them flexibly — and use them correctly — to achieve the best agricultural results.