 |
 |
 |
 |
||
 |
 |
 |
|||
|
|
|
|
|
||
|
|
|
|||
 |
|
body |
Problem: Rust on Turfgrasses - Puccinia sp.
Host Plants: All commonly grown turfgrasses
Description: Rust occurs to some extent on all turfgrasses
grown in Kansas; however, this disease is generally most severe on susceptible cultivars
of Kentucky bluegrass, perennial ryegrass, and zoysia grass. Rust normally appears in late
August to early September and continues through the fall months. Rust outbreaks are
dependent on favorable weather conditions. Therefore disease severity may vary
dramatically from one year to another.
From a distance, rust-infected turf appears dull yellow or light brown. Individual plants
may die and the turf becomes noticeably thin. The disease tends to be more severe in
partially shaded areas, such as under trees or along fences.
Diseased plants initially develop light-yellow flecks on the leaves. As the spots enlarge, the surfaces of the leaves rupture, exposing masses of powdery, brick-red spores of the fungus. The powdery material rubs off easily on your fingers, shoes or clothing. Rust-colored spores of the fungus are diagnostic of this disease. Continuous heavy infection causes many grass blades to turn yellow, wither and die. Severely rusted lawns may winterkill.
Recommendations: The rust fungi may overwinter in infected plants or be reintroduced into lawns each summer by wind-blown spores. Infection of leaf blades is favored by moderate temperatures (68° - 85° F) and extended wet periods. Once infection has occurred, disease development is favored by higher temperatures. Turfgrasses under stress (drought, shading, close mowing heights, high temperatures) are most likely to be seriously damaged by the disease.
Turfgrass provided with optimal levels of fertilizer and water is less likely to be
severely damaged by rust. Avoid night watering which increases the length of time the leaf
blades remain wet. Regular mowing, which severs infected leaf tips from the plant, will
help reduce inoculum levels. The best strategy is to mow frequently at a height not less
than what is recommended for the turfgrass. Avoid close mowing or scalping of the turf. It
is not necessary to remove clippings.
References:
1. Diseases of Turf, K-State Research and Extension Pub C-691
2. Rust Diseases of Turfgrasses, K-State Research and Extension Electronic Publication
Last Update: 03/28/2003
Extension Horticulture Home Page | Horticulture Information Center