Japanese oak wilt

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Japanese oak wilt (also called mortality of oak trees in Japan) is a fungal disease caused by Raffaelea quercivora fungus affecting by oak trees. In 1998, Japanese plant pathologists group was isolation, inoculation and reisolation the dead tree. [1] It is the first disease known that Raffaela fungus cause plant disease.

Contents

Symptoms

The first obvious symptom was that the leaves wilted, and many small holes appeared on the trunk. The leaves turned to red and died back quickly (1 or 2 weeks), and finally the tree died. If you cut the dead tree, you would discover the xylem had been discolored to brown. [2]

Mechanism

The oak trees react plugging their xylem with gum and tyloses for blocking the fungus spreading. [2] It's the same reaction of elm vs. Opiostoma fungus at Dutch elm disease.

Treatment

JOW treatment is resemble other fungus insect vector diseases such as Dutch elm disease or Pine wilt.

Exterminate beetle

The majority of this disease treatment is cut down the dead oak trees, and killed the vector ambrosia beetles by burned timber or infused insecticide.

Exterminate fungus

Some fungicide are developing and trying to inoculation.

See also

Raffaelea disease

Several tree wilt disease in the world

Mortality of oaks

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References

  1. Ito S., Kubono T., Sahasi N., Yamada T.(1998)Associated fungi with the mass mortality of oak trees. Journal of the Japanese Forestry Society 80(3), 170-175.
  2. 1 2 Kuroda, K.; Yamada, T. (1996). "Discoloration of sapwood and blockage of xylem sap ascent in the trunks of wilting Quercus spp. following attack by Platypus quercivorus". Journal of the Japanese Forestry Society. 78 (1): 84–88.

Further reading