拮抗菌 L2代谢产物对烟草赤星病病原菌的抑制效果

摘要

Colony diameter method,concave slide method,and hyphae immersion method were applied to determine the inhibition effects of an antagonistic bacteria L2 strain screened from Bijie,Guizhou on mycelia growth,spore germination,and conidia production of A.alternate.The results showed that the growth of A.alternate could be effectively inhibited under concentration of L2 aseptic filtrate from 1.5%~20%,and inhibited mycelia performed swelling,deformity,and protoplast aggregation obviously. Colony size were various with different content of coarse metabolites on plate.The inhibition on spore germination rate of pathogen was increased along with the increase of aseptic filtrate concentration.The germinal tube of inhibited spore performed abnormal germination,some of them showed vacuolization,and even rupture.Inhibitory effect of L2 metabolite filtrate on sporulation quantity of A.alternata reached 18.4% ~ 78.2%,and the higher the concentration,the stronger the inhibition ability.%为探明拮抗菌L2对烟草赤星病的抑制效果，采用菌落直径法、凹玻片法和菌丝浸泡法测定了拮抗菌 L2对烟草赤星病病原菌的菌丝生长、孢子萌发、产孢量的抑制作用。结果表明：拮抗菌 L2粗代谢物含量在1．5％～20％时均能有效地抑制烟草赤星病菌菌丝生长，7 d 时的抑制率在25．3％～74．8％，被抑制的菌丝出现了膨大、畸形、原生质聚集等现象，菌落大小随着平板粗代谢产物含量的增加而减小；对病原菌孢子萌发的抑制率随 L2粗代谢物浓度的增高而增高，24 h 时为11．4％～87．7％，孢子的芽管呈畸形萌发，部分产生液泡化并破裂；L2菌株粗代谢物滤液对烟草赤星病菌产孢的抑制率在18．4％～78．2％，浓度越高，抑制能力越强。