| 摘要: |
| 【目的】对花椒根腐病生防芽孢杆菌进行分离、筛选、定殖和防效评价，为开发高效、稳定、持久的生物农药提供理论与实践基础。【方法】采用稀释平板涂布法分离健康花椒根际土中的芽孢杆菌，利用点菌法和打孔法2次筛选拮抗效果最佳的芽孢杆菌，根据形态特征和生理生化试验对其进行初步鉴定，并测定其对1年生花椒根腐病的防治效果。用链霉素标记拮抗芽孢杆菌，并检测该菌在花椒根际及根内土壤中的定殖动态，以此为基础，运用灌根法对花椒根腐病进行预防和治疗处理，计算发病率、病情指数和防治效果。【结果】在分离获得的20株芽孢杆菌中，编号为B3的菌株拮抗作用最强，抑菌圈直径达26.0 mm，高温处理后仍具有活性，初步确定其为蜡样芽孢杆菌Bacillus cereus。盆栽试验结果表明，花椒根腐病发病率和病情指数随B3菌株发酵液稀释倍数增加而增加，B3发酵液原液至稀释200倍以下防治效果显著。定殖动态试验结果表明，无论病原菌存在与否，抗300 μg/mL链霉素的突变菌株均能在根际土壤和根内定殖，但根际土菌量大于根内，且早于根内达到峰值，随接种时间延长，定殖量下降并维持稳定。田间试验中，突变菌株B3无论预防还是治疗试验，均能发挥很好的效果，并优于原始菌株和化学农药双效灵。【结论】菌株B3能在花椒根际和根内很好地定殖、排挤病原物，具有对花椒根腐病进行生物防治的潜力和良好的发展前景。 |
| 关键词: 花椒 根腐病 腐皮镰刀菌 芽孢杆菌 生物防治 |
| DOI： |
| 分类号: |
| 基金项目:国家自然科技资源共享平台项目（2005DKA21207-13） |
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| Screening,identification,colonization and control effect of biocontrol Bacillus sp.against root rot of Zanthoxylum bungeanum Maxim. |
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LI Shujiang,ZHU Tianhui,QIAO Tianmin,et al
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| Abstract: |
| 【Objective】Biocontrol Bacillus sp.was isolated and screened and its colonization and control effect were evaluated to provide theoretical and practical basis for developing efficient,stable and abiding biopesticides.【Method】Bacillus sp.was isolated from rhizosphere soil of healthy prickly ash Zanthoxylum bungeanum Maxim.Bacillus sp.with optimal antagonistic effect was screened twice by point bacteria and stiletto methods,and identified by morphological characteristics and physiological-biochemical tests.The control effect on one-year-old Chinese prickly ash root rot was also dertermined.The antagonistic Bacillus sp.was marked by streptomycin and the colonization dynamic was analyzed in the root interior and rhizophere of Chinese prickly ash.Then,Chinese prickly ash root rots were treated by preventing and controling treatments,and the incidence,disease index,and control effect were calculated.【Result】Among the 20 Bacillus sp.strains obtained,the antagonistic effect of strain B3 was the strongest with the inhibition zone diameter of 26.0 mm.It kept activity after high-temperature treatment,and was preliminarily identified as Bacillus cereus.Pot experiment showed that the incidence and disease index increased along with the dilution time,and the control effects of strain B3 fermentation liquid diluted by less than 200 times were remarkable.The colonization dynamic results showed that the mutational strain against streptomycin of 300 μg/mL could colonize in the root interior and rhizophere no matter the pathogen existing or not.But the quantity in the rhizophere was more and the peak value appeared earlier than root interior.The colonization quantity declined and maintained stably along with the increase of inoculation time.In field experiment,the mutational strain B3 had good effects and was better than the original strain and mixed amino acid copper complex (CCMA) in both prevent testing and control testing.【Conclusion】Strain B3 can commendably colonize in the root interior and rhizophere of Chinese prickly ash and supplant the pathogen.Thus,it has biocontrol potential against Chinese prickly ash root rot and favourable developed prospect. |
| Key words: Zanthoxylum bungeanum Maxim. root rot Fusarium solani （Mart） Sacc. Bacillus sp. biocontrol |
