中文摘要：

【目的】探索利用植物病、健株根域土壤微生物区系比较法快速筛选高效、广谱且有实际防病促生作用生防真菌的可行性。【方法】根据菌落培养与扫描电镜形态特征及rDNA-ITS序列对拮抗真菌进行鉴定；生长速率法测定菌株无菌发酵滤液的拮抗活性，盖玻片对峙培养法观察拮抗真菌对草莓根腐病原菌菌丝形态的影响；室内发芽试验法测定真菌无菌发酵滤液促种子萌发活性；采用盆栽试验研究拮抗真菌对草莓根腐病的防病促生作用；土壤稀释平皿分离法测定拮抗真菌的定殖能力及对草莓根域微生物区系的影响。【结果】经鉴定，2株拮抗真菌HF3和HF7分别为灰黄青霉（Penicillium griseofulrum）和土曲霉（Aspergillus terreus），其无菌发酵滤液对7种供试病原真菌有较强的拮抗作用，培养96h时，HF3对立枯丝核菌（Rhizoctonia solani）和大丽轮枝菌（Verticillium dahliae）菌丝生长抑菌率均为100．0％。HF3菌丝对大双孢柱孢（Cylindrocarpon macrodidyma CF9）菌丝具有溶解作用，使病菌菌丝出现扭曲、变细、断裂及原生质浓缩等畸变现象；HF3和HF7 101和104倍稀释无菌发酵滤液可促进甜瓜种子萌发及胚根、胚芽生长。HF7 104倍稀释液对西瓜种子萌发及胚芽、胚根生长具有促进作用；HF3和HF7对盆栽草莓根腐病的防效分别达53．0％和46．9％，同时可促进盆栽草莓植株生长，提高果实产量；菌株HF3和HF7在草莓根表定殖数量分别为2．23×105、1．02×105CFU·g-1干土，同时减少了大双孢柱孢数量；接种HF3和HF7可有效调整草莓根域微生物区系，促进土壤微生态恢复平衡。【结论】通过植物病、健株根区土壤微生物区系比较可以快速筛选到高效广谱且有实际防病促生作用的生防真菌；HF3和HF7对草莓根腐病防治具有较高的潜在应用价值。

英文摘要：

[Objective] The objective of this study is to verify the suitability of a rapid screening program for biocontrol fungi based on root-zone microflora differentiae between healthy and root rot diseased strawberry plants. [Method] The isolated antagonistic fungi were identified according to colony and morphological characteristics observed by scanning electron microscope （SEM） and rDNA-ITS sequences analysis. Mycelium growth rate method and slide dual culture method were used to investigate antagonistic activity of cell-free culture filtrate and the antagonistic effect of antagonistic fungi against soil-bome pathogens, respectively. The seed germination promotion activity of culture filtrate was measured by Petri dish assays. A pot experiment was conducted to evaluate the control efficiency of antagonistic fungi against strawberry root rot caused by Cylindrocarpon macrodidyma CF9 and plant growth promotion effect. Colonization capacity and microbial flora were also determined by dilution plate count method. [ Result] Strain HF3 and strain HF7 were identified as Penicillium griseofulvum and Aspergillus terreus, respectively. The cell-free culture filtrate both of two strains exhibited strong antagonistic effect on mycelium growth of test pathogens. The mycelium inhibitory rate of strain HF3 culture filtrate on Rhizoctonia solani and Verticillium dahliae were 100.0% after 96 h. It was also observed that HF3 broke the hyphae of C. macrodidyma CF9, such as contorting, slimmer, bulging, dissolved, protoplasm condense. It was observed that 103 and 104 diluted-fold filtrate of two strains enhanced the melon seed germination and growth, 104 diluted-fold filtrate of HF7 promoted seed germination, plumule and radicle growth of watermelon. In a pot experiment, the control efficiency against root rot of strawberry of HF3 and HF7 were 53.0% and 46.9%, respectively. Moreover, two antagonistic strains exhibited strawberry plant growth promotion as well as fruit yield enhancement. HF3 and HF7 efficiently colonized strawberry ro