3株生防真菌的杀线虫活性及种类鉴定

大豆胞囊线虫是影响大豆产量的重要线虫,为了获得更多防治该线虫的真菌资源,在室内测定了生防菌D1、D7和A1孢子悬浮液对卵的寄生作用和发酵液的杀线虫活性。结果表明:孢子悬浮液处理12 d后,3株生防菌对大豆胞囊线虫卵的寄生率分别为68.83%、81.33%和79.50%。发酵液处理14 d后, 3株生防菌1×发酵液对卵孵化的抑制率分别为70.00%、77.78%和68.89%。3株生防菌发酵液处理3 d后,对二龄幼虫的校正死亡率分别为90.01%、86.74%和80.03%。通过形态学和rDNA-ITS序列比对及系统发育树分析,将菌株D1、D7和A1分别鉴定为曲霉属(Aspergillus sp.)、烟曲霉(A.fumigatus)和寄生曲霉(A.parasiticus)。

Nematocidal Activities and Species Identification of Three Biocontrol Fungi

Soybean cyst nematode(SCN) is an important nematode affecting soybean yield. In order to obtain more biocontrol fungi against SCN, we detected parasitic effects of spore suspensions of biocontrol fungi D1, D7 and A1 on eggs and nematocidal activity of fermentation broth on juveniles in laboratory. The results showed that after treated 12 d, the parasitic rate of spore suspension of the three strains on eggs respectively were 68.83%, 81.33% and 79.50%. After treated 14 d, the inhibition rates of fermentation broth of D1, D7 and A1 on egg hatching were 70.00%, 77.78% and 68.89%, respectively. After treated 3 d, the mortality rates of fermentation on the second-stagejuveniles were 90.01%, 86.74% and 80.03%, respectively. The strains D1, D7 and A1 were identified as Aspergillus sp., A.fumigatus, and A.parasiticus respectively according to morphological characteristics, rDNA-ITS sequence alignment and analysis of phylogenetic tree.