纹枯病菌胞壁降解酶对水稻组织和细胞的破坏作用

Damage of cell wall degrading enzymes produced by Rhizoctonia solani to rice tissue and cells

通过针刺接种,纹枯病菌(Rhizoctonia solani)胞壁降解酶——果胶酶(PG、PMG)和纤维素酶可使水稻叶鞘褪绿变黄。经浸泡处理,上述酶液使水稻愈伤组织细胞破裂崩解;水稻叶鞘细胞超微结构受到严重破坏,如细胞壁部分裂解、叶绿体和线粒体损伤等。这些结果提示病菌产生的胞壁降饵酶具有显著的致病作用。

The cell wall degrading enzymes such as polygalacturonase （PG）, pectin methylgalacturonase （PMG） and cellulase （Cx） were produced in improved Marcus＇s medium by Rhizoctonia solani Kuehn causing rice sheath blight. Through the wounding inoculation of the enzymes mentioned above, rice sheath became chlorotic and yellowing. By the immersion of the enzyme liquid, the cells of rice callus were broken; the ultrastructure of rice sheath cells was seriously damaged, some cell walls were cracked and the organella such as chloroplasts and mitochondria were destroyed. The results showed that the cell wall degrading enzymes produced by R. solani exerted significant pathogenicity to rice plants.