Koyaku disease - Koyakubyo

Japanese: こうやく病 - こうやくびょう

This disease is caused by a fungus that grows like a thin skin on the branches and trunks of many fruit trees and other trees, including mulberry, peach, cherry, plum, and elm, giving the appearance of a plaster, hence the name. The pathogen is a Septobasidium fungus, which belongs to the basidiomycete family, and lives in symbiosis with scale insects that live on the trees. The fungus develops using the secretions of the scale insects as nutrients and attaches itself to the trunk, creating a relationship in which the scale insects are protected by this skin-like mat of mycelium and suck sap from the tree. The damage suffered by trees is therefore a combination of damage caused by the scale insects sucking sap and damage caused by the fungus.

Source: Heibonsha World Encyclopedia, 2nd Edition Information

Japanese:

クワ，モモ，サクラ，ウメ，グミなど多くの果樹･樹木の枝や幹に，薄皮のように菌がはりつく病気で，ちょうど膏薬をはった趣を呈するのでこの名がある。担子菌に属するSeptobasidium菌が病原で，木につくカイガラムシと共生する。菌がカイガラムシの分泌物を栄養として発達して幹にはりつくと，カイガラムシはこの皮のような菌糸マットに保護されて木から汁液を吸うという関係ができ上がる。したがって樹木の受ける害は，カイガラムシの吸汁害と菌による損害の複合である。

出典　株式会社平凡社世界大百科事典第２版について　情報

<<: Koyazasa - Koyazasa

>>: Ointment - Kouyakuneri