How to Manage Pests

UC Pest Management Guidelines

DESCRIPTION OF THE DISEASE

Plants infected with stripe smut are often pale green and stunted with long, black stripes of spore pustules. Infected leaves curl, then die and become shredded. Fungal spores formed in the leaves can contaminate seed and infect seedlings and young tillers. The fungus survives in the grass plant.

SUSCEPTIBLE TURFGRASSES

Bentgrasses, perennial ryegrass, fescues, and bluegrasses are susceptible to stripe smut.

CONDITIONS FAVORING DISEASE

Stripe smut is favored by moderate temperatures and is prevalent in spring and fall. Temperatures between 60° to 78°F are conducive to infection and symptom expression. Infected plants may die in hot, dry weather.

MANAGEMENT

Cultural Control
Infected turf is generally under higher drought stress, so irrigate adequately based upon evapotranspiration needs, but avoid extended periods of prolonged leaf wetness. Avoid excessive nitrogen fertility during the summer months.

Treatment Decisions
Apply fungicides only if the disease is severe. Seed treated with a broad-spectrum fungicide like captan can possibly prevent initial infections of seedlings.

Common name		Example trade names	Ag Use R.E.I.+	NonAg Use R.E.I.+
(trade name)			(hours)	(hours)
When choosing a fungicide, consider general properties as well as information relating to environmental impact.
A.	AZOXYSTROBIN	Heritage
	MODE OF ACTION GROUP NAME (NUMBER1): Quinone outside inhibitor (11)		4	until dry
B.	CAPTAN	Captan
	MODE OF ACTION GROUP NAME (NUMBER1): Multi-site contact (M4)		4 days	until dry
	COMMENTS: Seed treatment for susceptible cultivars.
C.	CHLOROTHALONIL	Daconil
	MODE OF ACTION GROUP NAME (NUMBER1): Multi-site contact (M5)		12	until dry
D.	MANCOZEB	Fore, Dithane M-45
	MODE OF ACTION GROUP NAME (NUMBER1): Multi-site contact (M3)		24	until dry
	COMMENTS: Dithane M-45 registered for use on sod farms only.
E.	MYCLOBUTANIL	Eagle
	MODE OF ACTION GROUP NAME (NUMBER1): Demethylation inhibitor (3)		24	until dry
F.	PROPICONAZOLE	Banner Maxx
	MODE OF ACTION GROUP NAME (NUMBER1): Demethylation inhibitor (3)		24	until dry
G.	THIOPHANATE-METHYL	Fungo 50, T-Methyl E-Pro
	MODE OF ACTION GROUP NAME (NUMBER1): Methyl benzimidazole (1)		12	until dry
H.	TRIADIMEFON	Bayleton
	MODE OF ACTION GROUP NAME (NUMBER1): Demethylation inhibitor (3)		12	until dry
I.	TRIFLOXYSTROBIN	Compass
	MODE OF ACTION GROUP NAME (NUMBER1): Quinone outside inhibitor (11)		12	until dry
1	Group numbers are assigned by the Fungicide Resistance Action Committee (FRAC) according to different modes of actions (for more information, see http://www.frac.info/). Fungicides with a different group number are suitable to alternate in a resistance management program. In California, make no more than one application of fungicides with mode of action Group numbers 1, 4, 9, 11, or 17 before rotating to a fungicide with a different mode of action Group number; for fungicides with other Group numbers, make no more than two consecutive applications before rotating to fungicide with a different mode of action Group number.
+	Restricted entry interval (R.E.I.) is the number of hours (unless otherwise noted) from treatment until the treated area can be safely entered without protective clothing. Agricultural use applies to sod farms and commercial seed production.

PUBLICATION

UC IPM Pest Management Guidelines: Turfgrass
UC ANR Publication 3365-T
Diseases
F. Wong, Plant Pathology, UC Riverside
M. A. Harivandi, UC Cooperative Extension, Alameda County
Acknowledgment for contributions to Diseases:
J. Hartin, UC Cooperative Extension, San Bernardino County
M. E. Grebus, Plant Pathology, UC Riverside

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