木霉菌T38D对大豆根腐病菌的拮抗机制

Studies on Mechanism of Antagonism of Trichoderma T38D Against Pathogens of Soybean Root Rot

利用从土壤中分离出的木霉（Trichoderma spp.）菌株T38D,通过对峙法、对扣培养和圆盘滤膜法对引起大豆根腐病的病菌进行了拮抗作用研究,结果表明：木霉菌T38D对根腐病菌有明显的空间竞争能力,对立枯丝核菌和终极腐霉菌的拮抗系数达到Ⅰ级,对4种镰孢菌的拮抗系数均达到Ⅱ级;木霉菌T38D可以寄生于4种根腐病菌菌丝上,最终导致病原菌解体死亡;T38D的难挥发性代谢产物对立枯丝核菌的抑制率可达100%,对终极腐霉菌的抑制率为87.6%,对燕麦镰孢菌的抑制率为75.2%,对其余3种镰孢菌的抑制率都在40%～50%;T38D的易挥发性代谢产物对立枯丝核菌和终极腐霉菌有一定的抑制效果,对镰孢菌的抑制效果不明显。

The antagonism of Trichoderma spp.,T38D,from soil by our lab against pathogens of soybean root rot was studied by such as cultivating face to face and cultivating in sieve film of disc.The results showed that the antagonistic coefficient of T38D against Rhizoctonia solan and Pythium ultimum reachedⅠ,and reached Ⅱagainst Fusarium spp.The microscopic observation showed that pathogens causing soybean root rot can be parasitic on the mycelium and was cause to disintegrate and die by T38D.the hard volatile metabolite produced by T38D In the metabolites was an important antibacterial substance on the pathogens of soybean root rot,the inhibition rate of T38D against R.solan,P.ultimum and F.avenaceum was 100%,87.6% and 75.2%.the Inhibition rate of T38D against the other 3 Fusarium spp.reached 40%～50%.There were some effects when the easily volatile metabolite produced by T38D resisted R.solan and P.ultimum,and No significant effects when the easily volatile metabolite resisted Fusarium spp.