贝莱斯芽孢杆菌B4-7联合水稻秸秆生物炭对烟草青枯病的防治作用

【目的】探究贝莱斯芽孢杆菌B4-7联合水稻秸秆生物炭对烟草青枯病的防治效果,明确水稻秸秆生物炭对菌株B4-7防治烟草青枯病的增强作用,为进一步研发烟草青枯病的生防产品提供参考。【方法】采用平板培养法测定不同含量水稻秸秆生物炭(1%C、2%C、3%C和4%C)对烟草青枯病菌生长的抑制作用、吸附作用及运动性影响;通过盆栽试验测定菌株B4-7联合2%和5%水稻秸秆生物炭(B4-7+2%C、B4-7+5%C)对烟草的促生长作用及对烟草青枯病的防治作用。【结果】不同浓度的水稻秸秆生物炭对烟草青枯病菌均具有一定的生长抑制作用、吸附作用及运动性影响,与对照相比,1%C、2%C、3%C和4%C处理每培养皿中的青枯菌数量分别减少8.07%、37.01%、53.74%和69.29%,青枯菌的运动性分别减少28.57%、35.71%、42.86%和48.57%,对烟草青枯菌的吸附率分别为24.18%、42.42%、64.55%和81.97%。B4-7+5%C处理与对照相比,烟草株高、叶数、最大叶长和最大叶宽分别增加209.36%、27.98%、254.51%和185.09%;B4-7+5%C处理与B4-7单独处理相比,烟草株高和叶数均存在显著差异(P<0.05,下同),分别增加77.52%和11.74%。B4-7+5%C处理与对照相比,烟草青枯病发病率和病情指数分别显著减少81.33%和80.61%;B4-7+5%C处理与B4-7单独处理相比,烟草青枯病发病率和病情指数分别显著减少54.82%和45.29%,防治效果显著增加24.85%。【结论】水稻秸秆生物炭能增强生防细菌B4-7对烟草青枯病的防治效果,菌株B4-7联合5%水稻秸秆生物炭是烟草青枯病综合防控的一种有效措施,具有较大的应用前景,值得进一步推广和应用。

Control effect of Bacillus velezensis B4-7 combined with rice straw biochar on tobacco bacterial wilt

【Objective】To investigate control effect of rice straw biochar combined with by Bacillus velezensis B4-7on tobacco bacterial wilt,to make clear enhancement effect of rice straw biochar on tobacco bacterial wilt prevention and control by strain B4-7,so as to provide reference for developing biocontrol product to control the wilt.【Method】Influence of rice straw biochar(1% C,2% C,3% C and 4% C)on inhibition,adsorption and motility of tobacco bacterial wilt pathogen were determined by plate culture method. Pot experiment was conducted to determine the effect of strain B4-7combined with 2% and 5% rice straw biochar(B4-7+2% C and B4-7+5% C)on tobacco growth promotion and control effect on tobacco bacterial wilt.【Result】Different concentrations of rice straw biochar influenced growth inhibition,adsorption and motility of tobacco bacterial wilt pathogen. Compared with the control group,in media of 1% C,2% C,3% C and 4% C of biochar treatments,the number of bacteria in each medium decreased by 8.07%,37.01%,53.74% and69.29%,the motility of bacteria decreased by 28.57%,35.71%,42.86% and 48.57%,and the adsorption efficiency were24.18%,42.42%,64.55% and 81.97%,respectively. Compared with the control group,the plant height,leaf number,maximum leaf length and maximum leaf width of tobacco in B4-7+5% C treatment were increased by 209.36%,27.98%,254.51% and 185.09%. Compared with B4-7 treatment group,the plant height and leaf number of tobacco in B4-7+5% C treatment were significantly increased by 77.52% and 11.74%,respectively(P<0.05,the same below). Compared with the control group,the incidence and disease index of tobacco bacterial wilt in B4-7+5% C treatment were decreased by81.33% and 80.61%. Compared with B4-7 treatment group,the incidence and disease index of tobacco bacterial wilt in B4-7 + 5% C treatment were decreased by 54.82% and 45.29%,respectively,and the control effect was increased by24.85%.【Conclusion】Rice straw biochar can enhance the control effect of B. velezensis B4-7 on tobacco bacterial wilt,and the combination of B4-7 and 5% rice straw biochar forms an effective measure for comprehensive control of tobacco bacterial wilt,which has great application prospect and is worth further popularization and application.