玉米全蚀病菌（Ｇ．ｇ．ｍ）浸染寄主初期，匍匐菌丝在玉米根表纵向生长，然后产生侵染菌丝穿透根表皮向深层扩展，并形成大量附着枝。寄主根细胞对病菌穿透的反应是形成封闭的木质管鞘包围侵染菌丝。管鞘内菌丝穿透管鞘末端，向更深层细胞扩展，并重复同样的过程。病菌能侵染中柱，使中柱变褐坏死，但未见菌丝。 At the initial stage of host engulfing, the full-etiolated corbicula (G.g.m) of corn plants grew longitudinally on the root surface of maize, then the infected hyphae penetrated the epidermis of the root to extend deeper and formed a large number of adherent branches. The response of the host root cells to penetration by the germs is the formation of a closed wood sheath enclosing the infecting mycelium. Intrathecal mycelium penetrates the end of the sheath, spreading to deeper cells and repeating the same process. Bacteria can infect the column, the central column brown necrosis, but no mycelium.