FUNGICIDE

Merivon Fungicide

APVMA no.: 85698
Registrant: BASF AUSTRALIA LTD.
Formulation: SUSPENSION CONCENTRATE

Merivon Fungicide is a broad-spectrum co-formulated fungicide containing the active constituents fluxapyroxad and pyraclostrobin in a suspension concentrate formulation. Designed for foliar application, it combines two complementary modes of action to deliver robust preventative and systemic activity against key fungal diseases across tree fruits, tropical crops, and tree nuts.

In commercial production—from macadamia orchards in the Northern Rivers and Bundaberg to cherry blocks in Batlow and mango groves in the Atherton Tableland or Northern Territory—Merivon serves as a core protectant choice during critical crop growth stages. It provides activity on pathogens such as husk spot in macadamias, anthracnose and powdery mildew in mangoes, brown rot in stone fruit, and Botrytis in citrus.

Integrating Merivon early in disease-susceptible windows protects developing canopy and fruit tissues. Proper positioning within a broader orchard management program ensures maximum disease control while protecting yield quality and orchard health.

Active constituents

FLUXAPYROXAD250 g/L
PYRACLOSTROBIN250 g/L

Registered uses

Crop	Pest or disease
Cherry	Brown rot
Lemon	Botrytis (grey mould)
Macadamia	Husk spot
Mango	Anthracnose
Mango	Powdery mildew

Withholding period

Fruiting vegetables, Cucurbits, Citrus, and Mango: Nil
Almonds & Macadamias: DO NOT HARVEST FOR 21 DAYS AFTER APPLICATION.
Cherries: DO NOT HARVEST FOR 2 DAYS AFTER APPLICATION.

The registered withholding periods require no harvest withholding period (Nil) for citrus, mango, cucurbits, and fruiting vegetables. A 21-day withholding period prior to harvest applies to macadamias and almonds. A 2-day withholding period prior to harvest applies to cherries. Always confirm harvest timing in your orchard spray diary, and consult your packer or exporter regarding overseas Maximum Residue Limits (MRLs) and Export Withholding Periods (EWPs) prior to application.

Mode of action

Merivon Fungicide contains two active constituents with distinct biochemical mechanisms. Fluxapyroxad belongs to the Succinate Dehydrogenase Inhibitor (SDHI) class (FRAC Group 7), which inhibits complex II in the fungal mitochondrial respiration chain. Pyraclostrobin belongs to the Quinone Outside Inhibitor (QoI or strobilurin) class (FRAC Group 11), which inhibits complex III in fungal cellular respiration. Together, they block energy production at two separate target sites, inhibiting spore germination, germ tube elongation, and mycelial growth.

Resistance management

Merivon contains both Group 7 and Group 11 fungicides. Because both chemical classes carry a medium-to-high risk of resistance development in target pathogen populations, sound resistance management is essential. Rotate Merivon with fungicides from different FRAC groups (outside Group 7 and Group 11) in spray programs. Do not make consecutive applications beyond the limits specified on the approved label, and adhere strictly to Croplife Australia resistance management strategies for stone fruit, tropical fruit, tree nuts, and citrus crops.

Tank-mix compatibility

As a suspension concentrate formulation, Merivon is generally compatible with many standard orchard crop protection products and foliar nutrients. However, tank-mixing with emulsifiable concentrates (EC), crop oils, or wetters under extreme weather conditions or high temperatures may increase the risk of foliage or fruit marking. Always conduct a physical jar test before mixing unfamiliar combinations in the spray vat, and check the approved label for explicit mixing sequences and compatibility warnings.

Handling and environment

Merivon Fungicide is harmful to aquatic organisms; direct spray or drift into waterways, streams, or drains must be strictly avoided. Ensure appropriate drift management practices are implemented during application. Operators should wear recommended personal protective equipment (PPE) as stated on the safety directions. Refer to the approved APVMA product label for detailed personal protection equipment, re-entry periods, spray drift management constraints, and environmental safety precautions.

Common questions

When is the best timing to apply Merivon in a disease program?: Merivon is most effective when applied preventatively before fungal infection occurs, or at the earliest sign of disease during vulnerable crop stages such as flowering, early fruit set, or flush growth. Consult crop-specific label directions for precise timing.
Why does Merivon combine fluxapyroxad and pyraclostrobin?: Combining an SDHI (Group 7) active with a QoI (Group 11) active provides broad-spectrum disease control by disrupting fungal mitochondrial respiration at two distinct sites, offering strong preventative activity and built-in resistance management.
How do I manage fungicide resistance when using Merivon?: Avoid relying solely on Group 7 or Group 11 fungicides. Alternate Merivon with effective fungicides from different mode-of-action groups across the growing season and respect label limits on total seasonal applications.
How should spray volume be determined for canopy coverage?: Spray volumes must be calibrated to achieve complete and uniform coverage of all target foliage and fruit without runoff. Requirements vary based on tree canopy size, density, and equipment type; refer to the approved label for tree-crop spraying guidelines.
Where can I verify export requirements before picking?: Export Withholding Periods (EWPs) and foreign MRLs may differ from domestic harvest withholding periods. Check with your packing shed, exporter, peak industry body, or the manufacturer before spraying crops destined for export markets.