梨孢属（Pyricularia）真菌的产孢研究

Evaluation of culture techniques for stimulating sporulation of Pyricularia:

试验了１１种寄主梨孢菌在１５种培养基上的产孢差异，其中以大麦粒和高梁粒培养基产孢为优，适合水稻、狗尾草、粟、稗、牛筋草、茭白和碎米莎草等寄主梨孢菌的产孢培养；不同寄主梨孢菌在供试培养基上的产孢能力有较大差异，稻梨孢菌的产孢能力强，其次为牛筋草、稗、茭白和碎米莎草梨孢菌，马唐、毛马唐、李氏禾和罗氏草梨孢菌的产孢能力极差，在参试的１５种培养基上产孢均甚少，产孢差的菌株在蓝黑光灯，黑光灯和日光灯下照射可提高产孢量；培养皿敞开光照比覆盖光照有利于孢子的形成，光照培养时间对产孢也有影响。马唐、牛筋草、狗尾草梨孢菌接种到水稻感病品种原丰早上发病后再分离的菌株，产孢能力明显提高。

Pyicularia isolates from 11 host plants including rice and common weeds in paddy field, were tested on 15 culture media to observe their conidiospore production. Among the tested media, the sterilized grains of barley or sorghum showed abundent sporulation and were good for the spore production of the fungal isolates from Oryze sativa, Setaria viridis, S. italica, Echinochloa crusgalli, Eleusine indica, Zizania latifolia and Cyperus iria etc. The isolates from different host plants showed different levels of sporulation on the tested media. Rice isolates had the best sporulation. The isolates from E. indica, S. viridis, E. crusgalli, Z. latifoia and C. iria showed a medium level of sporulation. However, the isolates from Digitaria sanguinalis, D. sanguinalis var. ciliaris, Leesia hexandra and Rottbollia exaltata had very poor sporulation on the tested 15 tested media. The spore production of the most tested isolates increased when their cultures were exposed to blue-black or black light and fluorescent lamp. The exposure with the dish opened was more favorable to the sporulation. Lighting cuture time had much influence on sporulation, too. Moreover, the isolates from D. sanguinalis, S. viridis and E. indica showed markedly improved sporulation after they were inoculated on rice plants and reisolated later.