Inhibition comparison of several antagonists against Phytophthora infestans

To screen the potential of greater strain inhibiting Phytophthora infestans from antagonists obtained in previously experiments,the partial inhibitory characteristics of HT-6,SR13-2 and Sy11 strains against P.infestans were compared with dual-culture method and so on.The results showed that Sy11 strain displayed the strongest suppression to the pathogen in comparison with HT-6 and SR13-2.It had not the highest inhibition rates to mycelial growth(87.8%)but to releasing and germination of zoospores,as well as direct germination of sporangia,which were 95.1%,95.2% and 53.5%,respectively.In addition,Sy11 strain led to the most severe in mycelial deformity among them.However,no aberration of sporangia in shape was observed in all treatments with bacterial suspension of three antagonistic strains at different concentrations,only protoplast aggregation or sporangium wall breach.These results indicate that Sy11 strain has more potential in control potato late blight in future.