【摘要】 油桐是我国重要的木本油料植物,其生产的桐油作为天然的优良干性油在工业上具有广泛用途。但由油桐专化型尖孢镰孢菌Fusarium oxysporum f. sp. fordiis(Fof-1)侵染引起的枯萎病给油桐产业造成了毁灭性灾害,目前尚无有效防治手段。众多实践证明,利用生防菌可以有效防治土传枯萎病。本研究发现,在抗病油桐根围土壤中木霉菌的相对丰度较高,并从中分离获得了16株木霉菌;通过形态学鉴定和ITS-TEF1双基因联合构建系统进化树,鉴定出4种木霉菌:拟康宁木霉Trichodermakoningiopsis(TkonT1)、螺旋木霉T. spirale(TspiT2)、深绿木霉T. atroviride(TatrT3)和哈茨木霉T. harzianum(TharT4);通过对峙培养试验,发现木霉菌株TkonT1、TharT4和TspiT2具有较好的抑菌效果;进一步显微观察发现菌株TkonT1和TatrT3可缠绕在尖孢镰孢菌菌丝体上或穿入菌丝体内营寄生生长,吸收病菌菌丝体养分进而导致病菌菌丝体破裂和细胞原生质消解。结果表明,从抗病油桐根围土壤中获得的拮抗木霉菌株可用于油桐枯萎病的生物防治。更多还原

【Abstract】 Vernicia fordii(tung oil tree), an important industrial oil crop, usually suffers from a devastative disease caused by soil-borne Fusarium oxysporum f. sp. fordiis(Fof-1), and the effectiveness of chemical control for this Fusarium wilt disease is undesirable till now. It was found that the richness of Trichoderma species in rhizosphere soil of wilt-resistant tung oil trees was relatively high. In this study, 16 strains of Trichoderma were isolated from the rhizosphere soil samples of the wilt-resistant trees, and four strains antagonistic to F. oxysporum, T. koningiopsis Tkon T1, T. spirale TspiT2, T. atroviride TatrT3 and T. harzianum Thar T4, were screened. Microscopical observation proved that Tkon T1, Thar T4 and TspirT2 were confirmed to have better antifungal effect. TkonT1 and TatrT3 could wrap or penetrate the hyphae of Fof-1 and absorb nutrients from host, resulting in hyphal disruption and destruction. The results indicated that the Trichoderma species from wilt-resistant tree rhizosphere soil could be used for biocontrol of Fusarium wilt disease of V. fordii trees.更多还原