Table 9.10. Lettuce 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.
4 Apron XL
(mefenoxam) 100 lb
seed
4 Metastar 2E 8 pt Apply as a broadcast soil application and
(metalaxyl) incorporate into top 2 inches.
Pythium seedling
diseases
4 Ridomil Gold SC 2 pt 2
incorporated applications and surface
applications at the time of planting.
Ridomil Gold GR 40 lb 2
Ultra Flourish 4 pt 2
(mefenoxam)
4 & 11 Uniform SC
1000 ft of
row
1 appl. 0 Soil incorporated.
Rhizoctonia bottom rot 2 (iprodione) 2 pt 6 pt 14 1
Many brands available:
Enclosure 4F, Iprodione 4L AG,
Meteor, Nevado 4F, Rovral 4F
7 & 11 Luna Sensation
0 0.5 Apply at critical timing for disease suppression.
See extension guidelines for best application.
Rhizoctonia 7 Endura 11 oz 22 oz 14 0.5
(boscalid)
19 OSO 5%SC 0 4 hr See label for details.
(polyoxin D zinc salt)
Sclerotinia drop 2 (iprodione) 2 pt 6 pt 14 1
Many brands available:
Enclosure 4F, Iprodione 4L AG,
Meteor, Nevado 4F, Rovral 4F
7 Endura 70WG 11 oz 22 oz 14 0.5
(boscalid)
7 Fontelis 1.67SC 3 0.5
(penthiopyrad)
7 Kenja 400 SC (isofetamid) 14 0.5
second at thinning.
7 &11 Merivon Xemium 11 33 1 0.5 Alternate with fungicides with dissimilar modes
of action.
7 & 11 Luna Sensation
0 0.5 Alternate with fungicides of dissimilar modes of
action.
7 & 12
14 12 hr Do not make more than 2 sequential applications
without rotating to different mode of action. No
more than 2 applications at max. rate.
9 & 12 Switch 62.5WG 14 oz 56 oz 0 0.5 Alternate with fungicide with dissimilar modes of
action after 2 applications.
12 Cannonball WP
7 oz 28 oz 0 0.5 Apply after emergence and after thinning.
14 Botran 75W 5.33 lb 5.33 lb 14 0.5
(dichloran)
19 OSO 5%SC 0 4 hr See label for details.
(polyoxin D zinc salt)
Septoria 3 Rhyme
7 0.5 No more than 4 applications per season.
3 & 11 Topguard EQ
7 0.5 No more than 4 applications per season.
9 & 12 Switch 62.5WDG 14 oz 56 oz 0 0.5 Alternate with fungicide with dissimilar modes of
action after 2 applications.
7 Fontelis 1.67SC 3 0.5
7 &11 Merivon SC 11 33 1 0.5 Alternate with fungicides with dissimilar modes
of action.
2019 Vegetable Production Handbook of Florida 137