Japanese oak wilt
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's the first disease known that Raffaela fungus cause plant disease.
Symptoms
The first obvious symptom is the leaves wilt, and many small holes are on the trunk. The leaves turned to red and dieback quickly (1 or 2 weeks), finally the tree dead. If you cut the dead tree, you discovered the xylem are 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 ambrossia beetles by burned timber or infused insecticide.
Exterminate fungus
Some fungicide are developing and trying to inoculation.
See also
Raffaelea disease
- Laurel wilt - caused by R. lauricola, and R. canadensis
- Korean oak wilt - caused by R. quercus-mongolicae
Several tree wilt disease in the world
Mortality of oaks
References
- ↑ 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.
- 1 2 Kuroda, K. and 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
- Kamata, Naoto; Esaki, Koujiro; Kato, Kenryu; Oana, Hisahito; Igeta, Yutaka; Komura, Ryotaro 2007. Japanese oak wilt as a newly emerged forest pest in Japan: why does a symbiotic ambrosia fungus kill host trees?. In: Gottschalk, Kurt W., ed. Proceedings, 17th U.S. Department of Agriculture interagency research forum on gypsy moth and other invasive species 2006; Gen. Tech. Rep. NRS-P-10. Newtown Square, PA: U.S. Department of Agriculture, Forest Service, Northern Research Station: 1-3.