路德维希肠杆菌A18沿镰孢霉JK菌丝迁移的生态学效应  

Ecological effect of Enterobacter ludwigii A18 dispersal along hyphae of Fusarium sp.JK

作　　者：杨埔 王鹏然 张鑫 张犇 张丽珍[1] YANG Pu;WANG Pengran;ZHANG Xin;ZHANG Ben;ZHANG Lizhen(School of Life Science,Shanxi University,Taiyuan 030006,China)

机构地区：[1]山西大学生命科学学院,太原030006

出　　处：《应用与环境生物学报》2024年第1期151-157,共7页Chinese Journal of Applied and Environmental Biology

基　　金：国家自然科学基金青年基金项目(32101384);山西省基础研究计划青年科学研究项目(20210302124150);山西省高等学校科技创新项目(2019L0104)资助。

摘　　要：土壤细菌沿真菌菌丝的迁移可以扩大细菌的生境,增强其作用效果;然而,生防细菌的迁移对植物致病真菌的影响尚待深入研究.利用细菌-真菌共培养体系,研究生防细菌路德维希肠杆菌A18(Enterobacter ludwigii A18)沿植物致病真菌镰孢霉JK(Fusarium sp.JK)迁移的生态学效应.结果发现,在没有真菌菌丝存在的情况下,路德维希肠杆菌A18只能在3 g/L琼脂浓度的半固体培养基中游动,不能在更高浓度琼脂的培养基表面运动;而在镰孢霉JK存在的情况下,该细菌可以沿真菌菌丝迁移,在移动位点细菌的生物量可达108 CFU/g agar.在路德维希肠杆菌A18存在的情况下,镰孢霉JK的生长没有受到影响;然而,镰孢霉JK的产孢受到了路德维希肠杆菌A18的显著抑制,抑制率达90%.另外,路德维希肠杆菌A18可以黏附于镰孢霉JK菌丝表面形成生物膜,并利用镰孢霉JK分泌物生长,接种10 d后,路德维希肠杆菌A18的生物量从106.07±0.09 CFU/mL增加到109.07±0.10 CFU/mL.本研究表明路德维希肠杆菌A18沿镰孢霉JK菌丝迁移,不仅可以利用真菌分泌物生长,扩大其生境,而且可以抑制镰孢霉JK孢子的产生,减轻镰孢霉对农作物的危害.(图5表1参40)Migration of bacterial cells along fungal hyphae in soil can broaden bacterial niches and enhance their ecological function.However,the ecological effect of bacterial dispersal along phytopathogenic fungi needs further investigation.In this study,the ability of attachment and dispersal of Enterobacter ludwigii A18 along Fusarium sp.JK hyphae were investigated via a co-culture system,while the growth and sporulation of Fusarium sp.JK in the presence of E.ludwigii A18 was also explored.The results indicated that dispersion of E.ludwigii A18 was present in a semi-solid agar medium(3 g/L agar)and was absent when the agar concentration was higher than 5 g/L.However,E.ludwigii A18 could migrate along the fungal hyphae of Fusarium sp.JK,with the biomass reaching 108 CFU/g agar at the migration site.In the presence or absence of E.ludwigii A18,no significant difference was observed in the fungal growth rates.On the other hand,fungus sporulation was significantly suppressed at a 90%inhibition rate when Fusarium sp.JK was inoculated with E.ludwigii A18,compared to that in fungal monoculture.Bacterial biofilm formation on the surface of fungal hyphae was also confirmed by scanning electron microscopy.Additionally,fungal exudates could support the growth of E.ludwigii A18,with bacterial biomass increased from 106.07±0.09 CFU/mL to 109.07±0.10 CFU/mL.In conclusion,our data demonstrated that E.ludwigii A18 could disperse along fungal hyphae of Fusarium sp.JK,utilize fungal exudate and broaden bacterial niche.Additionally,E.ludwigii A18 could suppress the spore formation of Fusarium sp.JK,thus alleviating damage of phytopathogenic fungus to crops.

关 键 词：路德维希肠杆菌 镰孢霉 菌丝际 孢子 迁移 土壤 生防细菌 

分 类 号：S476[农业科学—农业昆虫与害虫防治]