Take-All Patch

Disease

Gaeumannomyces graminis f.sp. avenae


Take all patch is an important disease on bentgrass, particularly newly established stands of creeping bentgrass turf. The disease first appears in late spring or early summer, as a patch of bronze or bleached turf. The center of the patch eventually dies and is can give rise to weeds, particularly annual bluegrass. Spots range from 4-6 in. (10-15 cm) in diameter at first, but may grow into large patches, several feet in diameter over a period of years. Plants affected have shallow root systems, and are easily pulled out of the ground. Black runner hyphae of the fungus can be observed on crowns and roots microscopically.

The pathogen can survive on thatch and dead tissue as dormant mycelium. The fungus attacks crown and root tissues of the plant during the cool, wet weather of the spring and fall. It is most severe on newly established creeping bentgrass turfs. Development can be favored by applications of lime and by high soil pH.

  • Crops Affected: Turfgrass

    Damage

    The location of this disease is golf courses. General symptoms are a circle, patch, wilting, and irregular coloring. Foliar symptoms are browning, and yellowing. This can occur during the months of May, June, July, August, September, and October. Hosts of the disease are Creeping Bentgrass, Colonial Bent, Annual Ryegrass, and Velvet Bentgrass.

    Management

    Proper nitrogen fertility is important in managing take-all patch. Urea-based fertilizers tend to be effective in managing the disease when applied at adequate levels to creeping bentgrass turf stands. Liming should be avoided in areas where take-all is a problem. Soil pH should be below 6.5, preferably between 5.5 and 6.0. Manganese deficiency has shown to greatly enhance take-all patch development, therefore adequate manganese fertility should be practiced depending on soil and tissue analyses. Excessive irrigation should be avoided as well.

    Timing of fungicide applications for the preventive management of take-all patch is important.

    Early Season: Fenarimol, myclobutanil, propiconazole, or azoxystrobin among others should be applied about two weeks after initial mowing, followed by a second application 30 days later.

    Mid-to-Late Summer: For areas with chronic, reoccurring take-all patch, make application approximately two weeks before night time temperatures drop into the 50's (50° F; 10° C).