【摘要】 为筛选出对苹果叶枯病菌细极链格孢(Alternaria tenuissima)和苹果斑点落叶病菌交链格孢(A.alternata)具有高效拮抗及对病害具有防治作用的生防芽胞杆菌，采用纸碟法和含药培养基法测定了5种芽胞杆菌对A.tenuissima和A.alternata的抑制效果，采用离体叶片接种法测定了其对两种病害的防治效果。结果表明，以5种芽胞杆菌发酵液处理A.tenuissima和A.alternata时，枯草芽胞杆菌B2(Bacillus subtilis)发酵液对2种病原菌的抑菌效果最佳，处理7d后其抑菌率分别为79.84%和79.82%。随着5种芽胞杆菌发酵滤液稀释倍数的增加，不同稀释倍数发酵滤液对2种病原菌的抑菌效果逐渐减弱，其中枯草芽胞杆菌B2发酵滤液稀释5倍时抑菌率分别为98.38%和96.30%。离体防效结果表明，枯草芽胞杆菌B2发酵滤液对苹果叶枯病和斑点落叶病防治效果分别为68.10%和65.70%。因此，枯草芽胞杆菌B2对苹果叶枯病菌和苹果斑点落叶病菌生长抑制及病害防治效果最佳。更多还原

【Abstract】 This study aimed to screen biocontrol strains of Bacillus with strong antagonistic activity against the apple leaf blight pathogen(Alternaria tenuissima) and apple leaf spot pathogen(A.alternata),and to evaluate their disease control efficacy.The inhibition rates of five biocontrol Bacillus strains against A.tenuissima and A.alternata were assessed using paper disc diffusion method and fermentation filtrate-amended medium method.The control efficacy against the two diseases was evaluated using an in vitro leaf inoculation method.The results showed that B.subtilis B2 exhibited the highest antagonistic activity against both pathogens after treatment with the fermentation broth of five biocontrol Bacillus strains.The inhibition rates of B.subtilis B2 for A.tenuissima and A.alternata on the 7th day were 79.84% and 79.82%,respectively.With increasing dilution levels of the fermentation filtrates of the five Bacillus strains, the inhibitory effect on A.tenuissima and A.alternata gradually decreased.Among the five Bacillus strains tested, the inhibition rates of B.subtilis B2 fermentation filtrate on A.tenuissima and A.alternata were 98.38% and 96.30% at a 5-fold dilution, respectively.In addition, control efficacy of B.subtilis B2 fermentation filtrate on apple leaf blight and leaf spot diseases was 68.10% and 65.70%,respectively.Therefore, B.subtilis B2 exhibited the highest inhibitory effect on the growth of A.tenuissima and A.alternata,and demonstrated strong biocontrol efficacy.更多还原