【摘要】 对烟草低头黑病菌 (Colletotrichumcapsici(Sdy)Bulter&Bisbyf.nicotianaeG .M .Zhang&G .Z .Jiang)无菌培养毒素滤液进行生物测定 ,筛选强产毒菌株和最佳产毒条件。结果表明 :① 8株烟草低头黑病菌皆能产生对烟草NC82有致萎作用的毒素类物质 ,以菌株C -Ⅲ - 1产毒最强 ,萎蔫指数达到 98.33% ;C -Ⅰ - 1和C -Ⅱ - 1产毒最弱 ,萎蔫指数仅为 4 0 .0 0 %左右。②以C -Ⅴ - 1为目标菌株对病菌产毒条件进行测定 ,得到最佳产毒模式 :pH =6 ,2 5℃或30℃ ,PDB培养基中连续黑暗振荡培养 13d。③活体植株浸根法作为烟草低头黑病菌毒素的生物测定跟踪方法是较适宜的。更多还原

【Abstract】 The cultural filtrate of Colletotrichum capsici(Sdy)Bulter & Bisby f. nicotianae G.M.Zhang & G.Z.Jiang was used to bioassay, by which it was expected to gain the strong toxin-producing strains and the optimum toxin-producing conditions. The result showed that all of the strains could produce pathotoxins in cultural media. C-Ⅲ-1、C-Ⅴ-1and C-Ⅲ-5 were the best three toxin-producing strains, and C-Ⅲ-1 was the best of them, its wilting index was up to 98.33%; C-Ⅰ-1 and C-Ⅱ-1were the second and the third. The optimum toxin-producing mode was: under pH=6 and 25℃ or 30℃ for 15 days by vibrating in darkness, and PDB, tabacco leaf broth and maltose liquid medium were suitable for Colletotrichum capsici f.nicotianae toxin production. The result also showed that intribital tabacco seedlings root-soaking was the feasible method for the bioassay of Colletotrichum capsici f. nicotianae toxin.更多还原