内生放线菌SG2与生防放线菌SC11融合菌株的筛选

Screening of recombinants of endophytic actinomycetes SG2 and biocontrol actinomycetes SC11

【目的】提高生防放线菌对枯、黄萎病的防治效果。【方法】运用原生质体融合技术,对内生放线菌SG2和生防放线菌SC11进行融合,测定了融合菌株对尖镰孢西瓜专化型和大丽轮枝菌的抑菌效果,并测定了其内生性和产多胺的能力。【结果】获得了G-C1-G-C18共18株形态特征和菌落颜色与亲本菌株有差异、遗传性状稳定的融合菌株,其中G-C1、G-C2、G-C8、G-C10、G-C11、G-C12、G-C16和G-C18等8株融合菌株对大丽轮枝菌的抑菌率均≥70%,G-C12和G-C8对尖镰孢西瓜专化型的抑菌率均>75%。融合菌株分泌物的抑菌效果均有所降低。融合菌株G-C1、G-C2、G-C10、G-C11、G-C12和G-C16继承了亲本SG2的内生性;上述8株融合菌株均继承了双亲产生多胺的特性。【结论】实现了植物内生放线菌和土壤中生防防线菌的原生质体融合,为枯、黄萎病的生物防治奠定了基础。

[Objective] The study was to improve the effect of the biocontrol antinomycetes against the verticillium wilt and fusarium wilt. [Method] The protoplast fusion to fuse the endophytic actinomycetes SG2 and the biocontrol antinomycetes SCll was used. [ Result] Eighteen recombinants were isolated based on the morphological character, color of colony and stabilization characteristics of genetics, and determined their inhibition, the difference between the volume of secretions, as well as the endophytic character and the capacity of producing polyamines. The eight recombinants G-C1, G-C2, G-C8, G-C10, G-C11, G-C12, G-C16 and G-C18 had obvious inhibiting effects（≥70%） on Verticillium dahliae. The strain G-C12 and G-C8 had obvious inhibiting effects（〉 75%） on Fusarium oxysporurn f. sp. niveumo But the recombinants reduced the volume of secretions. Recombinants G-C1, G-C2, G-C10, G-C11, G-C12 and G-C16 were isolated from two different plants and also could produce polyamines. The parents＇ endophytic character and producing polyamines were maintained by eight recombinant strains. [Conclusion] Apparently, this study has achieved the proteplast fusion between endophytic antinomycetes and biocontrol antinomycetes, and has become one of the most promising alternatives in controling the verticiuium wilt and fusarium wilt.