Control Effect of Three Microbial Agents on Tomato Gray Mould

To screen efficient fungicides for controlling tomato gray mould,three microbial agents were chosen to study their control effects on Botrytis cinerea and tomato gray mould,which included 10billion spores/g Bacillus subtilis WP,1million spores/g Pythium oligandrum WP and 0.6billion spores/g Trichoderma harzianum T-22.The PDA plate inhibition test showed that the inhibition rate of Bacillus subtilis diluted 150times was 100%on Botrytis cinerea,which was significantly better than the chemical agent,50% procymidone WP.The inhibition rates of Pythium oligandrumdiluted 500times and Trichoderma harzianum T-22diluted 300times were 86.76%and 76.96%,respectively.The pot tests showed that three microbial agents exhibited both preventive effect and therapeutic effect against tomato gray mould.The preventive effect was 75.62%-84.44%and the therapeutic effect was 68.75%-78.06%by the highest dose,so the preventive effect of microbial agents was better than their therapeutic effect against tomato gray mould.