Fungicide Product News

Kate Everts, Vegetable Pathologist, University of Delaware and University of Maryland;

ZeroTol 2.0 is a hydrogen dioxide and peroxyacetic acid product that has been added to the OMRI products list. ZeroTol is a broad-spectrum bactericide/fungicide that is registered to manage plant pathogens on greenhouse-grown fruits, vegetables and herbs.

Meg McGrath at Cornell provided the following information on a new product, Zing!, that may be useful for managing fall cucurbits: “Zing! is a new fungicide that has the same active ingredient with targeted activity for oomycete pathogens as Gavel but is applied at a slightly higher rate (0.2 lb/A zoxamide versus 0.12-0.17 lb/A with an application of Gavel, depending on the rate used). Both fungicides also contain a protectant. Gavel contains mancozeb and thus has 48-hr REI and 5-day PHI. Zing! contains chlorothalonil and thus has 12-hr REI and 0-day PHI. The amount of chlorothalonil in Zing! is an intermediate rate (1.18 lb/A chlorothalonil) of the labeled rate range for downy mildew in products with just chlorothalonil (1.125-1.5 lb/A). Chlorothalonil is labeled for use at a higher rate (1.5-2.25) to manage several other diseases including powdery mildew. Growers trying to manage these diseases as well as downy mildew should apply additional Bravo to bring the amount of chlorothalonil up to the higher rate. This necessitates applying Bravo at less than lowest labeled rate. It is acceptable to apply a pesticide at less than labeled rates for agricultural purposes only, unless the labeling specifically prohibits such use. There is not a prohibiting statement on the Bravo label. To obtain an application rate of 1.5-2.25 lb/A chlorothalonil, tank mix Bravo WeatherStik at 0.43-1.43 pt/A with Zing!. Zing! is labeled for use at 36 fl oz/A; maximum seasonal use is 8 applications with no more than 2 sequential applications permitted before it must be alternated with another fungicide.”