Product Name: Monopotassium Phosphite
Chemical Formula: KH₂PO₃
CAS Number: 13977-65-6
Molecular Weight: 120.08 g/mol
Appearance: White crystalline powder
Solubility: Highly soluble in water
Other Names: Potassium dihydrogen phosphite, potassium phosphonate

Product Overview

Monopotassium Phosphite is a water-soluble phosphorus compound used primarily as a plant nutrient and fungicidal agent. It is widely applied in modern agriculture to enhance plant immunity, stimulate root development, and protect against fungal diseases such as Phytophthora and Pythium. Unlike conventional phosphates, phosphites are absorbed directly into plant tissues and exhibit systemic mobility.

Chemical Structure and Mechanism

Monopotassium Phosphite contains phosphorus in the +3 oxidation state (phosphorous acid base), making it more bioavailable than phosphates (which have phosphorus in +5 oxidation state). Once absorbed, it translocates through xylem and phloem tissues, promoting resistance mechanisms within the plant and suppressing certain pathogens.

Production Method

Monopotassium Phosphite is produced through a neutralization reaction between phosphorous acid (H₃PO₃) and potassium hydroxide (KOH) or potassium carbonate (K₂CO₃):

Reaction:
H₃PO₃ + KOH → KH₂PO₃ + H₂O

This process yields high-purity crystalline monopotassium phosphite with excellent solubility and shelf stability. The final product is dried, milled, and screened to ensure consistent granule size and free-flowing powder suitable for water-soluble fertilizers and foliar sprays.

Typical Specifications

Applications

1. Agricultural Fertilizer

• Source of phosphorus and potassium for crops

• Enhances plant vigor, root strength, and photosynthetic efficiency

• Suitable for foliar spray, fertigation, and hydroponics

2. Fungicidal Agent

• Acts systemically against oomycete fungi (Phytophthora, Pythium, Downy mildew)

• Induces plant defense-related gene expression

3. Plant Immunity Booster

• Stimulates salicylic acid and jasmonic acid pathways

• Enhances disease resistance in fruits, vegetables, grapes, and ornamental plants

4. Greenhouse and Hydroponic Cultivation

• Improves nutrient uptake in controlled-environment agriculture

• Compatible with most water-soluble fertilizers

Key Benefits

• High bioavailability of phosphorus

• Dual functionality: nutrition + disease control

• Rapid absorption and systemic movement in plants

• Reduced need for synthetic fungicides

• Environmentally friendly and non-toxic to beneficial microbes

• Compatible with integrated pest and nutrient management (IPNM)

Packaging and Storage

• Standard Packaging: 25kg kraft paper bags or plastic-lined PE bags

• Storage Conditions: Cool, dry place; avoid moisture and direct sunlight

• Shelf Life: 24 months under proper storage

About the Manufacturer

Jiangsu Khonor Chemicals Co., Limited
As a leading supplier of high-purity phosphite fertilizers from China, we offer:

• Consistent quality with third-party testing support

• OEM labeling and custom packaging

• Free technical support and documentation (COA, TDS, MSDS)

• Worldwide delivery and flexible shipping solutions

• Over 10 years of experience in agrochemical export

Ordering Information

• Free sample available

• Lead time: 5–10 working days

• Bulk quantities and customized solutions available on request

TDS - Monopotassium phosphite.pdf

COA - Monopotassium phosphite- 21092001.pdf