Disease Control : New England Vegetable Management Guide : UMass Amherst

Parsley & Cilantro - General Parsley & Cilantro Insect Control Parsley & Cilantro Weed Control

Bacterial Leaf Spot of Cilantro (Pseudomonas syringae pv. coriandricola)

The initial symptoms of bacterial leaf spot are dark, water-soaked, vein-delimited spots on leaves. The spots rapidly turn dark brown in color, remain angular in shape, and can be seen from both top and bottom sides of leaves. If disease symptoms are severe, the foliage can take on a blighted appearance when leaf spots coalesce. Wilting may be observed. The disease progresses rapidly during wet weather. Crops with significant damage will be unmarketable. The causal bacterium is host specific to cilantro and does not infect celery or parsley. The pathogen is seedborne in cilantro and infested seed is the primary means by which the pathogen gets into the production system. The bacterium can also survive many years in the soil as an opportunistic bacterium. If bacterial leaf spot has been a problem, rotate out of cilantro for several years. Use management practices that promote airflow and do not work with plants when wet.

FRAC Group BM02:

Bacillus amyloliquefaciens strain D747 (Double Nickel 55^OG): 0.125 to 1 lb/A (soil), 0.25 to 3 lb/A (foliar); PHI 0d, REI 4h.

FRAC Group M01:

basic copper sulfate (Cuprofix Ultra 40 Disperss): 1.3lbs/A for cilantro; PHI 0d, REI 48h. See label for phytotoxicity restrictions. Do not apply more than once every 10 days.

Powdery Mildew (several genera)

Disease development is favored by high humidity, moderate temperatures, and drought stress. Rain or overhead irrigation reduces disease severity. Powdery mildew fungi survive between crop cycles on weed hosts, and some genera also survive in infected crop debris. Control weeds and volunteer Apiaceous plants. Maintain adequate fertilizer and irrigation programs to ensure plant health. Drought stress may be lessened with mulching. Use resistant cultivars when available.

FRAC Group 7:

fluopyram (Velum Prime): 6 to 6.84 fl oz/A; PHI 0d, REI 12h.
fluxapyroxad + pyraclostrobin (Merivon Xemium): 4 to 5.5 fl oz/A; PHI 1d, REI 12h, Groups 7 & 11. Parsley only.

FRAC Group 11:

fluxapyroxad + pyraclostrobin (Merivon Xemium): 4 to 5.5 fl oz/A; PHI 1d, REI 12h, Groups 7 & 11. Parsley only.

FRAC Group P05:

Reynoutria sachalinensis extract (Regalia ^OG): 0.5 to 1 q/A; PHI 0d, REI 4h.

FRAC Group BM02:

Streptomyces lydicus strain WYEC 108 (Actinovate AG^OG): 3 to 12 oz/A; PHI 0d, REI 4h. Apply to foliage with spreader-sticker for best results.
Swinglea glutinosa extract (EcoSwing ^OG): 1.5 to 2 pt/A; PHI 0d, REI 4h.

Root rot (Pythium and Phytophthora spp.)

These pathogens are soil-borne and cause severe symptoms in cold, wet soils. Look for collapsed plants shortly after emergence. Roots and possibly crowns will be brown and soft. Provide good soil drainage and reduce soil compaction. Raised beds may be useful.

FRAC Group 4: Phenylamides

mefenoxam (Ridomil Gold SL): 1 to 2 pt/A; PHI 7d for fresh, 21d for dried, REI 48h. May be used pre-plant or as soil spray.

Septoria Leaf Spot/Blight (Septoria spp.)

Symptoms appear as small tan lesions on leaves and petioles with dark borders and small black specks in the center. Spots may enlarge and coalesce, blighting large portions of the leaves. Severe outbreaks can significantly reduce crop quality. The pathogen survives on infected crop debris and is also known to be seedborne. Disease development is highly favored by wet, humid conditions. Start with certified disease-free seed or treat seed with hot water or fungicides. Inspect transplants before setting in the field and destroy infected plants. Rotate to crops outside of the Apiaceae family. Plant sequential plantings as far apart from one another as possible. Incorporate plant residues promptly after harvest. Manage weeds that may also serve as hosts.

FRAC Group 7: SDHI (succinate dehydrogenase inhibitors)

penthiopyrad (Fontelis): 14 to 24 fl oz/A; PHI 3d, REI 12h.
pydiflumetofen + fludioxonil (Miravis Prime): 9.2 to 13.4 fl oz/A, PHI 0d, REI 12h, Groups 7 & 12.

FRAC Group 9: AP fungicides (anilinopyrimidines)

cyprodinil (Switch 62.5 WG): 11 to 14 oz/A; PHI 7d, REI 12h, Groups 9 & 12. Cilantro only.

FRAC Group 11: Quinone outside inhibitors

pyraclostrobin (Cabrio EG): 12 to 16 oz/A; PHI 0d, REI 12h. Parsley only.

FRAC Group 12: PP fungicides (phenylpyrroles)

cyprodinil (Switch 62.5 WG): 11 to 14 oz/A; PHI 7d, REI 12h, Groups 9 & 12. Cilantro only.
pydiflumetofen + fludioxonil (Miravis Prime): 9.2 to 13.4 fl oz/A, PHI 0d, REI 12h, Groups 7 & 12.

White Mold (Sclerotinia sclerotiorum)

White mold is characterized by robust white mycelium and irregular black sclerotia in and/or on infected stems. Plants may turn yellow and collapse. Start with certified seed that is free from sclerotia of the pathogen. Infected plants will wilt and a white, cottony fungal mass can often be observed near the soil line. Rotate with non-host plants. Irrigate in the morning to promote drying of soil and foliage. This pathogen thrives in 50˚F–70˚F temperatures and cool, damp conditions. Ten or more days of wet soil promotes infection. Soil sterilization with heat, chemicals, steam, or by biofumigation with brassica crops can reduce, but not eliminate, sclerotia.