GENESIS AND FUNCTION OF DEFENSE STRUCTURE OF SCLEROTIA OF GRIFOLA UMBELLATA AFTER ARMILLARIELLA MELLEA INFECTON
蜜环菌侵染后猪苓菌核防御结构的发生及功能

The infection of Armillariella mellea could induce the genesis of defensee structure of the sclerotia of Grifola umbellata,such as the appearance of crystals in sclerotium cells,the occurrence of thick-walled hyphae,and the pla- smolysis at the hypodermal layer of sclerotia.A few thick-walled hyphae appear in the sclerotia as the rhizomorph of A.mellea adheres to the sclerotium epidermis, and then they increase in number and are closely arranged to form the wall of pri- mary isolation cavity.The invader together with part of sclerotia are enclosed in the cavity.The secondary isolation cavity subsequently develops in the outside of the primary one.The rhizomorph and cortical hyphae of A.mellea could break through the walls of primary and secondary or even third isolation cavities.The character and function of defense structure of sclerotia are discussed in this paper.