Flexible fungicides

Syngenta Technical Services Manager Nancy Rechcigl explains how to control diseases on ornamental crops through the use of Positiva.

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Photos courtesy of Syngenta
 

Greenhouse Management: How is Postiva a unique fungicide in the ornamental market, and what diseases does it control?

Nancy Rechcigl: PostivaTM fungicide from Syngenta features two powerful active ingredients in a unique combination to protect against more than 30 foliar diseases that affect ornamental plants. Postiva is powered by ADEPIDYN® technology, the first member of a subclass of SDHIs (succinate dehydrogenase inhibitors) within FRAC Group 7, and difenoconazole, a demethylation inhibitor (DMI) in FRAC Group 3.

Postiva helps prevent many difficult-to-control diseases such as Botrytis, powdery mildew, leaf spots, rusts and more. It also protects against root and crown diseases caused by Sclerotinia, Rhizoctonia and Fusarium, while suppressing bacterial pathogens caused by Xanthomonas spp. and Pseudomonas spp.

GM: What crops is Postiva labeled for?

NR: Growers can apply Postiva to many types of ornamental crops, including bulb crops, cut flowers, evergreens (including conifers), pot and bedding plants, foliage plants, ornamental trees and shrubs, succulents, non-bearing fruit and nut plants, vegetable plants grown for retail sales and more.

Source: Krasnow, Vero Beach Research Center, 2019. Treatments applied on Jan. 6, 2019. Plants inoculated on Jan. 27, 2019. DAT = days after treatment.

GM: Where and how can Postiva be applied?

NR: A very flexible product, Postiva is labeled for use in greenhouses, nurseries (including field- and container-grown plants) and conifer nurseries, as well as for residential and commercial landscapes and interior plantscapes. It can be applied as a spray, including aerial application, as well as a drench, chemigation or through automated cold fogging in greenhouses.

GM: How does Postiva provide growers a different Fusarium solution?

NR: Postiva is proven to control Fusarium more consistently than other available treatments. Notoriously hard to control, Fusarium infections begin in the soil and move upward from the roots into the stem and leaves, where they become more evident. While Fusarium may not be an annual threat, it is very difficult to manage when it does appear and can cause significant damage.

Many ornamental crops are susceptible to Fusarium during production, but the primary crops to monitor are cyclamen, mums and dianthus, with mums being the most critical. Growers of these crops should treat for Fusarium preventively by incorporating Postiva into their fungicide rotation.

GM: What makes Postiva a great addition to existing rotation programs?

NR: The two modes of action in Postiva provide a strong defense against various pathogens and can also help delay the development of resistance. When rotated with Mural®, Palladium® and Daconil® brand fungicides, Postiva can help strengthen season-long disease management programs.

All photos are either the property of Syngenta or are used with permission.

Performance assessments are based upon results or analysis of public information, field observations and/or internal Syngenta evaluations. Trials reflect treatment rates and mixing partners commonly recommended in the marketplace.

© 2025 Syngenta. Important: Always read and follow label instructions. Some products may not be registered for sale or use in all states or counties and/or may have state-specific use requirements. Please check with your local extension service to ensure registration and proper use. ADEPIDYN®, Daconil®, GreenCast®, Mural®, Palladium®, Postiva™ and the Syngenta logo are trademarks of a Syngenta Group Company. Orkestra® is a trademark of BASF. All other trademarks are the property of their respective third-party owners.

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