Metam-Sodium: A Versatile Soil Fumigant for Crop Protection

Technical Introduction

Metam-Sodium (IUPAC: sodium N-methyldithiocarbamate) is a pre-plant soil fumigant widely used for controlling a broad spectrum of soil-borne pests, pathogens, and weeds. Upon application, Metam-Sodium decomposes into methyl isothiocyanate (MITC), a highly reactive compound responsible for its pesticidal activity.

• Mode of Action: MITC disrupts cellular functions of fungi, nematodes, and weeds, leading to their death.

• Systemicity: Acts as a soil fumigant, penetrating soil pores to target pathogens and pests below the surface.

• Target Spectrum: Controls nematodes, soil fungi (like Fusarium, Pythium), bacteria, and weed seeds.

Applications

• Field Crops:

  • Pre-plant soil treatment for potatoes, sugarcane, cotton, and tomatoes to manage nematodes and soil-borne diseases.

• Vegetables:

  • Applied in cucumbers, melons, peppers, and eggplant to reduce Fusarium, Verticillium, and root-knot nematodes.

• Ornamentals & Turf:

  • Used to control root pathogens and nematodes in ornamental plants, greenhouses, and turfgrass.

• Weed Management:

  • Effective against weed seeds and seedlings, especially annual grasses and broadleaf weeds.

Advantages

• Broad-Spectrum Control: Effective against fungi, nematodes, bacteria, and weeds simultaneously.

• Soil Penetration: Gas-phase action ensures control in deep soil layers that contact sprays cannot reach.

• Rapid Action: Converts quickly to MITC, providing immediate control after incorporation.

• Compatibility: Can be used before planting a wide range of crops; often integrated into pre-plant soil preparation.

• Resistance Management: Useful in rotational pest management, reducing the risk of pathogen resistance.

Specifications (Typical Parameters)

FAQ

Q1: How is Metam-Sodium applied?
A: Typically applied via soil incorporation, shank injection, or drip irrigation, then covered with plastic to retain fumigant gases.

Q2: Is Metam-Sodium systemic?
A: No. It acts only in soil and is not absorbed by plants. Its active component, MITC, is highly volatile and targets soil-borne pests.

Q3: How long should I wait after application before planting?
A: Typically 7–21 days, depending on soil temperature, moisture, and crop sensitivity. Always follow label instructions.

Q4: Does Metam-Sodium control above-ground pests?
A: No. It is a soil fumigant targeting nematodes, fungi, bacteria, and weed seeds. Foliar pests require separate insecticides.

Q5: Are there environmental concerns?
A: Yes. MITC is highly toxic to aquatic organisms, and Metam-Sodium can volatilize into the atmosphere. Proper soil sealing, buffer zones, and PPE are required during application.