Pristine Fungicide (pyraclostrobin + boscalid), EPA#7969-199, READ THE LABEL
Pristine contains two unrelated active ingredients, pyraclostrobin and boscalid, with a high risk of disease resistance development. Pyraclostrobin is a strobilurin fungicide that provides excellent activity against downy mildew and powdery mildew, very good activity against black rot, some activity against phomopsis, and excellent activity against botrytis at higher rates. It also provides very good control of bitter rot and ripe rot, and some suppression of the sour rot disease complex. Boscalid provides excellent control of powdery mildew, and fair to excellent control of botrytis, depending on the use rate. Thus, Pristine provides excellent control of downy mildew, powdery mildew, and black rot, fair to good control of phomopsis, fair control of botrytis at the 8 to 12.5 ounce per acre application rate, and good to excellent control of botrytis at the 19 ounces per acre rate. Pristine is phytotoxic on ‘Concord’ and ‘Noiret’, so should not be used on these varieties. It should also be used with caution on ‘Steuben’ and ‘Rougheon’, where injury has occurred irregularly. Powdery mildew and downy mildew resistance to the strobilurin fungicides is known to occur widely in the Eastern United States. The boscalid component of Pristine is also at risk for powdery mildew resistance development. In order to minimize the resistance development of Pristine where it has not already occurred, limit applications of Pristine and strobilurin fungicides to a maximum of 2 per season, rotate them with other unrelated fungicides, and tank mix with sulfur on non-sulfur-sensitive varieties. 12 hour/5 day reentry interval (see label for details), 14 days to harvest.