Your Reading List

New products available for potato growers in 2017

Late blight in potatoes.


Aprovia fungicide is a new alternative for the control of verticillium wilt. Aprovia contains the fungicide Solatenol, a SDHI (succinate dehydrogenase inhibitor) fungicide from FRAC Group 7. It is registered for in-furrow application to suppress verticillium wilt, silver scurf and rhizoctonia (black scurf, and stem and stolon canker).

Aprovia Top

Aprovia Top fungicide combines difenoconazole (FRAC Group 3) with Solatenol (FRAC Group 7) in order to control alternaria-caused early blight and to suppress alternaria-caused brown spot. Because Solatenol is slowly metabolized by the plant, it provides a longer residual activity. As soon as it dries out, Aprovia Top becomes rainfast and, thanks to the translaminar property of its two active ingredients, it shelters both sides of the leaf.

Double Nickel 55 WDG

Potato growers now have access to a new biofungicide called Double Nickel, which controls white mould and early blight as a foliar spray. Applied in the furrow, it also suppresses rhizoctonia canker. Double Nickel belongs to a new class of fungicidal-bactericidal agents (Group 44), whose active ingredients are made up of biological products presenting low risk for the environment.

Manufactured by Certis USA, Double Nickel is registered in five countries, including the United States, where growers have been using it for more than two years. Double Nickel contains the D747 strain of the beneficial rhizobacteria Bacillus amyloliquefaciens as well as its metabolites that are factory-produced through fermentation. These metabolites, called lipopeptides, destroy pathogenic fungi and bacteria found on leaf and root surfaces by damaging their cell membrane.

When Double Nickel is applied in the soil, Bacillus amyloliquefaciens quickly colonizes the roots, thus creating a biofilm that prevents initiation of root diseases while destroying pathogenic fungi populating the rhizosphere. Double Nickel is an effective tool for managing resistance to chemical fungicides, and is an important part of an integrated pest management program. It presents little risk to the bees and other beneficial insects. Re-entry interval after its application is only four hours, and it can be sprayed at low rates up until the day of harvest.

This biofungicide is available as water-dispersible granules (WDG) or as a liquid concentrate (LC). It leaves no visible residue on the plants treated and can be tank mixed with other pesticides including copper-based fungicides.


United Phosphorus offers its new Elixir fungicide, recently registered in Canada and created exclusively for potato production. It is composed of chlorothalonil and mancozeb. These two very popular active ingredients control early and late blight of potatoes.

Chlorothalonil is the active ingredient of Bravo 500, Bravo Zn, Echo 90 DF and Echo 720. As for mancozeb, it is the active ingredient of Dithane 75 DG, Manzate Pro-Stick and Penncozeb 75 DF. The discovery of these two active ingredients dates back to the 1960s. Their multi-site mode of action ranks them inside Group M.

Applied early in the season, Elixir efficiently controls early and late blight. It can be applied up to 10 times per season. This inexpensive fungicide will be available for the 2017 season.

Elixir makes it possible to have a product containing both active ingredients in the form of water-dispersible granules.

Orondis UItra

Orondis Ultra provides long-lasting protection against potato late blight using two modes of action. It combines mandipropamid (active ingredient of Revus — Group 40) with oxathiapiprolin, a new active ingredient from Group U15, thus ensuring effective control of late blight. Oxathiapiprolin enters the leaf surface and moves upwards inside the plant, protecting both existing tissues and new growth. This new active ingredient has an innovative mode of action that delivers superior residual control of late blight. It safeguards the new growth by undergoing a systemic and “acropetal” movement within the plant.

Field trials carried out at the Honeywood research station in Florida and in Plattsville, Ont., have shown Orondis Ultra could offer protection against late blight up to 21 days after a preventive application.


Valent has applied for a spring 2017 minor registration in Canada for the use of Presidio fungicide for suppression of pink rot. This product, whose active ingredient is fluopicolide (Group 43), is already registered for the control of late blight in potato.

Fluopicolide’s mode of action is typical of the systemic fungicides used specifically against oomycete fungi: it disrupts many steps in their reproductive cycle. For a maximum protection when using this product as a foliar spray, it is preferable to tank mix it with a chlorothalonil-based product.

Presidio allows for a protective, curative, controlling and antisporulating action. Its active ingredient fluopicolide acts as a locally systemic and translaminar penetrating agent (as a foliar spray); it works systemically by moving inside the plant xylem. Presidio fungicide is particularly efficient as part of a regular spraying program, and in association and alternatively with other effective fungicides relying on a different mode of action (that is, from a group other than Group 43).

For controlling pink rot, Presidio must be applied as a band at planting or with directed spray on row sides between hilling and tuber initiation.

Field experiments in Maine (Dave Lambert, University of Maine) with potato variety “Russet Norkotah” have shown Presidio to perform a better suppression of pink rot as compared with many other products currently used against this disease.


Already known as an effective product against early blight, Quash is a fungicide composed of metconazole, from the triazole family (Group 3). Quash provides a broad-spectrum action that inhibits the fungus’s sterol biosynthesis. It has a systemic activity. Quash is quickly absorbed by the tissues of the plant inside which it can move upwards, but not downwards. Metconazole does not affect the spore germination of fungi. However, it disrupts other mechanisms in their life cycle’s early stages. Quash is particularly efficient when applied before infection.

Quash is now registered for suppression of white mould caused by Sclerotinia sclerotiorum. For a vigorous suppression, Quash must be sprayed before infection, generally at row closure.

Scientists from the U.S. company Miller Research report a significant yield increase in potatoes treated with the fungicide Quash. Jeff Miller, president and CEO of the research firm, believes this yield increase is brought about by a physiological change in potato plants which tend to be shorter and greener when treated with Quash.

Sencor STZ

Bayer expects its herbicide Sencor STZ to be registered in the spring of 2017. Sencor STZ will combine the action of Sencor 75 DF (Group 5) with that of a Group 14 herbicide. In fact, we will have access to a product mixing metribuzin, the active ingredient of Sencor 75 DF, and sulfentrazone (Group 14).

The idea is to create a barrier at the soil surface fighting the weeds listed on the label of Sencor 75 DF and those resistant to triazines — including lamb’s-quarters and all types of pigweed — with the additional aid of sulfentrazone.

Velum Prime

On November 16 Bayer announced Canadian registration of Velum Prime, a non-fumigant potato nematicide. Velum Prime’s active ingredient is fluopyram.

This nematode-controlling product introduces a new mode of action and thus a new chemical family (pyridinyl ethyl benzamide). Velum Prime’s label states it suppresses root-borne nematodes, northern root-knot nematode, and potato cyst nematodes, including pale cyst and golden nematode.

According to Bayer’s Jon Weinmaster, “Velum Prime provides protection against a yield-robbing pest that, for many growers, didn’t have a viable solution outside of fumigants.”

Velum Prime must be applied in-furrow at planting. Moreover, this in-furrow application has the added benefit to protect the potato plant against early blight. However, it is important to keep monitoring this disease all summer long. The use of foliar fungicides with a different mode of action will help reduce resistance development and strengthen early blight control later in the season.

Potato diseases, weeds and parasites. photo: File

About the author



Stories from our other publications