Manzate Max, a new liquid formulation fungicide, is now available for use on potatoes to combat early and late blight.
“An option for managing both early and late blight is Manzate Max fungicide, which is now labelled for potatoes in Canada,” said Holly Derksen, UPL territory sales manager. “It is a liquid formulation, which is easier and safer to use and handle, especially when making multiple applications throughout the season.”
Why it matters: As a multi-site protectant fungicide (FRAC M3), Manzate Max provides effective control of early and late blight in potatoes, with low risk of resistance developing.
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It also addresses many other diseases, because its active ingredient, mancozeb, is an economical, broad-spectrum fungicide, explained Derksen.
She cautioned producers that early and late blight could overlap outside of the beginning and end of the season, requiring ongoing scouting.
“Monitoring weather conditions is an important and proactive step growers should take throughout the season to monitor for these destructive diseases,” she explained. “Both diseases thrive when conditions are humid, with early blight often emerging in warm temperatures and late blight showing up when the daytime temperatures are moderate, and the nights are cooler.”
She recommends that growers spray when weather conditions are favourable for disease development or when it is detected.
Late blight can also persist for extended periods by surviving on infected cull and seed tubers, as well as tubers left in the field after harvest. If infected tubers are stored, they can lead to significant post-harvest losses in a potato crop.
“Make sure your cull and compost piles are kept away from growing areas,” advised Derksen. “Anything you wear scouting your fields should be cleaned and sterilized to minimize the risk of spreading disease. Rubberized apparel works best for this.”