顶孢霉菌代谢产物对玉米圆斑病菌生长和发育的影响

Effect of Acremonium sp.Metabolites on the Growth and Development of Helminthosporium carbonum

利用菌丝生长速率法和孢子萌发法研究顶孢霉代谢产物对玉米圆斑病菌生长的抑制能力。结果表明,顶孢霉发酵液对玉米圆斑病菌分生孢子萌发和菌丝生长均有抑制作用。菌丝生长速率测定表明,含有顶孢霉菌代谢产物的培养基(D+P)圆斑病菌菌丝的生长速率低于含有玉米圆斑病菌代谢产物的培养基(Y+P)和空白对照PDA的生长速率,菌丝生长速率分别为65.0、86.5、87.5 mm/d;以Y+P和PDA为对照,D+P对玉米圆斑病菌在第1天和第2天时抑制率最高,均达58%以上;在1 mL PDA体系中,顶孢霉发酵液添加量为0.5 mL时,抑制率可达100%,不同浓度处理间及其与对照处理间顶孢霉发酵液抑制率差异显著(P=0.05);同一处理不同培养天数顶孢霉发酵液抑制率也有显著差异(P=0.05)。孢子萌发实验表明,经顶孢霉发酵液处理后的玉米圆斑孢子萌发率降低,在发酵液浓度为0.9 mL/mL时,萌发率仅为24%,抑制率可达66.67%,EC50约为68 mL/100 mL,且孢子经发酵液处理后产生畸形,不能正常发育。

By the methods of mycelial growth rate and spore germination, the inhibition ability ofA cremonium sp. fermentation on H. carbonum was studied. The result showed that the restrain ability of the fermentation broth of A cremonium sp. on spore germination and mycelial growth of H. carbonum were obviously. The mycelial growth rate determination showed that the mycelia growth rate treated by respectively PDA medium contains metabolic substances of A cremonium sp.（D＋P） was less than by respectively PDA medium contains metabolic substances of H. Carbonum （Y＋P） and PDA control, the mycelia growth rate treated by D＋P, Y＋P and PDA control was respectively 65.0, 86.5, 87.5 mm/d. Relative to Y＋P treatment and PDA control, the inhibition rate of H. carbonum spore germination treated by D＋P on 1 d and 2 d, are highest, both more than 58%. In 1 mL PDA system, the inhibition rate was up to 100%, when added 0.5 mL A cremonium sp. fermentation broth, it was different significantly between different fermentation broth concentration treatment and PDA control（P=0.05）; it was also different when cultured different days in one con- centration treatment （P=0.05）. Spore germination experiment showed that the spore germination reduced after treated by A cremonium sp. fermentation broth, when the fermentation broth concentration was 0.9 mL/mL, the germination percentage was only 24%, inhibition rate was up to 66.67%, EC50 was about 68 mL/100 mL. And spores was deformed when treated by the fermentation broth, can not develop normally.