中文摘要：

通过分生孢子萌发试验、菌丝抑制试验、接种离体枝条试验及田间病斑涂抹药剂防治试验，研究了7株植物内生放线菌对苹果树腐烂病的防治效果。结果表明，7株植物内生放线菌无菌发酵滤液对病原菌分生孢子萌发及菌丝生长均有明显的抑制作用，2倍稀释液对孢子萌发抑制率均达85％以上，20倍稀释液对菌丝生长抑制率均达80％以上。显微观察发现，Hhs．015（BAR1—5）菌株无菌发酵滤液可导致病菌芽管、菌丝畸形。在人工接种条件下，无菌发酵滤液原液对离体枝条病斑扩展具有明显的抑制作用，其中AR1—14、Hhs．015（BAR1—5）和TGYXCSA-7处理5天后防治效果分别达83．2％、69．7％和85．6％。田间刮除病斑后涂抹放线菌发酵原液也可明显抑制病斑复发，防效均达80％以上。

英文摘要：

The effect and control efficacy of 7 strains of endophytic actinomycetes on Valsa ceratosperma, the pathogen of apple tree valsa canker, were tested by conidial germination, mycelial growth as well as twigs lesion control in excised twigs and in field trial. The inhibition rates of 7 strains of endophytic actinomycetes on conidia germination were more than 85% after treated with 2 times dilution of cell-free fermentation liquid. The inhibition rates on mycelial growth were more than 80% after treated with 20 times dilution of cell-free fermentation liquid. It was found that the germ tubes and mycelium of V. ceratosperma exhibited obvious malformation after treated with the cell-free fermentation liquid of Hhs. 015 （ BAR1-5 ） strain. After spreading the wound with the cell-free fermentation liquid of the 7 stains of endophytic actinomycetes and inoculating the mycelia cake on excised twigs, development of lesions were inhibited remarkably 5 d later. The control efficiency of AR1-14, Hhs. 015 and TGYXCSA-7 were 83.2% , 69.7% and 85.6%, respectively. In the field trails, the control efficiency in lesion recrudesce were more than 80% after spreading the fermentation liquids of actinomycete strains on the wounds.