Mushroom ring

Name: Mushroom ring

Another name: fairy ring disease.

Distribution: distributed throughout the country.

Host: All lawn grasses.

Characteristics: In spring and early summer, moist lawns may appear circular or curved dark green or concentric circles formed by fast-growing (crazy) grass circles that occasionally grow weak or dormant, or dead grass. Sometimes secondary circles of overgrown grass appear within circles of dead grass.

When the soil is dry, especially in autumn, the outermost ring of overgrown grass may disappear, leaving the grass in the outermost ring dead and the grass in the inner ring overgrown. After mild weather, rain or flooding, mushrooms can grow on overgrown grass rings. Mushroom rings begin suddenly.

Mushroom circles can be divided into three types according to symptoms: the first type has a circle surrounded by dead grass and one or two circles surrounded by dark green crazy grass. The second type consists of a circle of dark, wild grass with mushrooms growing in it. The third type, with a ring of mushrooms, basically has no obvious effect on lawn growth. In either case, mushrooms are produced only temporarily.

Pathogen: Fungi. More than 20 genera and 50 species of fungi belong to basidiomycetes. The most common are Leiota, Lycoperdon, Marasmius, Scleroderma and Tri-choloma. Among them, mushroom rings caused by M.oreades are the most common.

Occurrence characteristics: Initially, the disease is usually surrounded by a small circle or a bunch of mushrooms. The diameter of the mushroom ring increases by a few centimeters every year, sometimes up to 0.5 meters. With the mushroom circle bacteria to the rapid growth outside the circle, the circle of old bacteria gradually died, followed by the emergence of the phenomenon of excessive growth of grass in the inner circle. In the second type of mushroom ring, the inner ring and outer ring are overgrown at the same time, and there is no dead grass zone. The disease is most serious in sandy loam soil with low fertility and insufficient water. Shallow irrigation, shallow fertilization, thick straw layer and drought were all beneficial to the occurrence of disease.

Prevention and control measures:

1. Ensure that the soil moisture is sufficient and maintain the soil card in a very wet state.

2, soil fumigation, fumigation before the disease should be removed after the lawn. Changing diseased soil is a quick way to eliminate germs. Soil tillage and mixing involves removing whole sod and mixing the soil with heavy rotary cultivators. The tilled land is best soaked in water to promote growth of antagonistic microorganisms against mushroom ring fungus.

3. Remove the withered layer in time, irrigate deeply and remove mushrooms.

4, if necessary, methyl bromide or formaldehyde fumigation soil, can also be perforated irrigation chlorothalonil, etc.