Table 12.6. Onion fungicides ordered by disease and then FRAC group according to their mode of action. (continued)
Pertinent Diseases
Fungicide
Chemical
or Pathogens
Group1
(active ingredients)
Max. Rate/Acre Min. Days to
Applic. Season Harvest Reentry Remarks2
Labels change frequently. Be sure to read a current product label before applying any chemical.
Many brands available:
phite, K-Phite 7LP, Oxiphos, Phiticide,
Phostrol, Prophyt, Rampart, Reveille
40 Forum 6 oz 30 oz 0 0.5 Must be applied in a tank mix with another
fungicide active against downy mildew. Do not
make more than 2 sequential applications.
(dimethomorph)
40 Revus
(dry);
(green)
7 4 hr Make no more than 2 consecutive appl.
before switching to a non-group 40 fungicide.
A silicon-based adjuvant must be added at
recommended rates.
(mandipropamid)
43 Presidio 2 0.5 Do not make more than 4 applications of
Presidio per season.
21 Actigard 50WG 1 oz. 4 oz 7 0.5 Do not apply to plants that are stressed or prior
or within 5 days transplanting. Suppression
only.
(Acibenzolar-s-methyl)
40 & 45 Zampro 0 0.5 See label
(dimethomorph + ametoctradin)
Iris Yellow Spot (Iris
yellow spot virus)
21 Actigard 50WG 1 oz. 4 oz 7 0.5 Do not apply to plants that are stressed or prior
or within 5 days transplanting. Suppression
(Suppression only) (acibenzolar-S-methyl) only.
Powdery mildew M2 (sulfur) SEE INDIVIDUAL
LABEL
0 1 Do not use during hot weather or within 4
Many brands available: weeks of an oil application.
Sulfur, Microthiol Disperss, Sulfur 90W,
Yellow Jacket Wettable Sulfur
7 Fontelis 3 0.5
(penthiopyrad)
9 & 3 Inspire Super See label 14
(green);
7 (dry
bulb)
0.5 Do not make more than 2 applications before
(cyprodinil + difenoconazole) alternate with a different fungicide group.
11 & 3 Quadris Top 7 0.5 Make no more than 1 application before
alternating to another fungicide with a non- QoI
(Group 11) mode for action
(azoxystrobin + difenoconazole)
11 Cabrio EG 12 oz 72 oz 7 0.5 Alternate applications with a different fungicide
(pyraclostrobin) group. Make no more than 5 appl/crop.
Purple blotch M1 (copper compounds) SEE INIDIVIDUAL
LABEL
0 Varies
from 4
hr to 2
days.
Frequent use of copper fungicides may cause
(Alternaria porri) Many brands available: foliar burn.
Badge SC, Badge X2, Basic Copper 53,
C-O-C-S WDG, Champ DP, Champ F2
FL, Champ WG, C-O-C DF, C-O-C WP,
Cueva, Cuproxat, Kentan DF, Kocide
3000, Kocide 2000, Kocide DF, Kophydroxide,
Nordox, Nordox 75WP, Nu
Cop 3L, Nu Cop 50DF, Nu Cop HB
M3 (mancozeb) SEE INDIVIDUAL
LABEL
7 1 Do not apply to exposed bulbs.
Many brands available:
Dithane DF, Dithane F45, Dithane M45,
Koverall, Manzate, Manzate Pro-Stik,
Penncozeb 4FL, Penncozeb 75DF,
Penncozeb 80WP, Roper DF
M5 (chlorothalonil) SEE INDIVIDUAL
LABEL
7 (dry
bulb);
14
(green)
1
Many brands available:
Bravo Ultrex, Bravo Weather Stik,
Bravo Zn, Chloronil 720, Chlorothalonil
720 EC, Echo 720, Echo 90 DF, Echo
Zn, Equus 500 Zn, Equus 720 SST,
Equus DF, Initiate 720, Initiate Zn
218 2019 Vegetable Production Handbook of Florida