Introduction
Naphthaleneacetic acid (NAA) is a synthetic plant hormone belonging to the auxin family. It plays a vital role in regulating plant growth processes such as cell elongation, root initiation, fruit setting, and prevention of premature fruit drop. NAA is widely used in agriculture, horticulture, and tissue culture for its effectiveness and stability.
Product Overview
Chemical Name: 1-Naphthaleneacetic acid
Molecular Formula: C₁₂H₁₀O₂
CAS Number: 86-87-3
Appearance: White to off-white crystalline powder
Solubility: Slightly soluble in water, soluble in ethanol and acetone
Formulations: Powder, tablet, liquid (SL), and soluble concentrate
Key Features
Rooting Agent: Promotes adventitious root formation in cuttings
Fruit Retention: Prevents premature fruit drop in apples, citrus, etc.
Stable Compound: More chemically stable than natural auxins
Targeted Effect: Effective at low concentrations with long-lasting action
Main Applications
| Application | Effect |
|---|---|
| Rooting of cuttings | Enhances root initiation in woody and herbaceous plants |
| Fruit drop prevention | Used in citrus, apples, and olives to reduce early fruit fall |
| Tissue culture | Supports callus induction and root regeneration |
| Yield improvement | Enhances fruit size and uniformity |
| Transplant shock recovery | Promotes root growth in transplants |
Usage Guidelines
Concentration: 10–100 ppm depending on plant type and purpose
Application Methods: Foliar spray, dipping cuttings, soil drench
Timing: Apply during active growth or before stress periods (e.g., flowering, transplanting)
Compatibility: Can be used with other PGRs or micronutrients after compatibility testing
Advantages
✅ Cost-effective and long-lasting
✅ Boosts rooting success and fruit yield
✅ Versatile for multiple crops and stages
✅ Easy to formulate and apply
Limitations
❌ Overapplication can cause abnormal growth or phytotoxicity
❌ Limited mobility in plant once absorbed
❌ Must be used precisely to avoid unwanted hormonal imbalances
❌ May degrade under UV light, requiring proper storage
Safety and Handling
PPE: Use gloves, goggles, and protective clothing during handling
Toxicity: Low mammalian toxicity, but avoid inhalation or ingestion
Storage: Keep in cool, dry, and dark conditions
Shelf Life: Stable for up to 2 years under proper storage
FAQs
Q: Is NAA natural or synthetic?
A: NAA is a synthetic auxin, designed to mimic the effects of natural plant hormones.
Q: Can I use NAA on food crops?
A: Yes, but follow local regulations and recommended residue limits.
Q: Can NAA replace natural rooting hormones?
A: Yes, it is often more stable and effective than natural auxins like IAA.
Conclusion
Naphthaleneacetic acid is a powerful plant growth regulator that offers broad utility across crop types and stages. Whether used to root cuttings or prevent fruit drop, NAA delivers reliable and precise hormonal control, making it an essential tool in modern plant production.