Rally® 40WSP fungicide is a member of the sterol inhibitor (SI) class of fungicides. It controls a broad-spectrum of diseases, including powdery mildew, and is labeled for many perennial and annual crops.
For powdery mildew, apply at the first sign of infection. While Rally does have some curative ability (i.e. reachback), it should primarily be used as a protectant fungicide.
Proper resistance management for powdery mildew in grapes requires use of different classes of fungicides.
Prevent Fungus with consistent performance on powdery mildew in high and low pressure situations Highly systemic action Studies prove that the active ingredient in Rally moves in the direction of new growth faster than other products Systemic activity resists wash-off from rain or irrigation Economical. Based on the price per acre of Rally and the price per day of control, Rally delivers outstanding return on investment Short re-entry interval of 24 hours Packaged in convenient water soluble packets, which represent a totally closed mixing system and require no additional personal protective equipment Aerial label in many vegetable and row crops Additional diseases controlled include brown rot, anthracnose, various rusts, shot-hole, leaf spot and leaf blight ... Labeled for use in grapes, stone fruit, tomatoes, cucurbits, strawberries and other crops
ePestSolutions offers a wide variety of turf fungicides and ornamental fungicides including Prostar fungicide, Heritage fungicide etc.
Q: what is the formula for applying rally 40 wsp to grape vines showing powdery mildew
A: The rate is 3 to 5 ounces per acre of rally.
http://www.epestsolutions.com/Rally-40WSP-Fungicide-Compared-to-20-Ounces.html here is the link to the label page so you can have a copy.