中国水稻科学 ›› 2022, Vol. 36 ›› Issue (6): 623-638.DOI: 10.16819/j.1001-7216.2022.211102

• 研究报告 • 上一篇    下一篇

硫藤黄链霉菌St-79对水稻白叶枯病的防效和促生作用

马静静, 潘妍妍, 杨孙玉悦, 王嘉琦, 蒋冬花()   

  1. 浙江师范大学 化学与生命科学学院, 浙江 金华 321004
  • 收稿日期:2021-11-02 修回日期:2022-04-05 出版日期:2022-11-10 发布日期:2022-11-10
  • 通讯作者: 蒋冬花
  • 基金资助:
    国家自然科学基金资助项目(31570013);浙江省基础公益研究计划资助项目(LGN22C140004)

Control Effect of St-79 (Streptomyces thioluteus) on Rice Bacterial Blight and Its Growth-promoting Effect

MA Jingjing, PAN Yanyan, YANG Sunyuyue, WANG Jiaqi, JIANG Donghua()   

  1. College of Chemistry and Life Science, Zhejiang Normal University, Jinhua 321004, China
  • Received:2021-11-02 Revised:2022-04-05 Online:2022-11-10 Published:2022-11-10
  • Contact: JIANG Donghua

摘要:

【目的】水稻白叶枯病是水稻的主要细菌性病害之一,严重影响水稻生产。本研究获得一株有效防治水稻白叶枯病的放线菌菌株,探索其对白叶枯病的防效和促进水稻生长的作用,为生防菌的开发利用提供科学依据。【方法】利用梯度稀释涂布法、共培养法和牛津杯法筛选拮抗水稻白叶枯病菌(Xanthomonas oryzae pv. oryzae, Xoo)的放线菌菌株;通过形态特征、生理生化反应、16S rDNA序列和系统发育树分析对其进行分类鉴定;利用共培养法分析目标菌株的抗菌谱;通过96孔板微量稀释法、扫描电子显微镜、微生物粘附碳氢化合物法等探究目标菌株的抑菌作用;通过发酵滤液浸种与菌液喷洒土壤的方法探究其对水稻生长的促进作用;利用盆栽试验探索目标菌株发酵滤液对水稻白叶枯病的防治效果。【结果】从不同生境土壤中分离出140株放线菌菌株,最终筛选得到一株对Xoo具有强拮抗活性的放线菌菌株St-79,其发酵滤液抑菌圈直径为64 mm,并鉴定其为硫藤黄链霉菌(Streptomyces thioluteus)。菌株St-79对水稻细菌性条斑病菌(Xanthomonas oryzae pv. oryzicola)、大豆细菌性斑疹病菌(Xanthomonas axonopodis pv. glycines)、油菜黑腐病菌(Xanthomonas campestris pv. campestris)和番茄细菌性叶斑病菌(Pseudomonas syringae pv. tomato)均有拮抗作用。其乙酸乙酯粗提物具有良好的抑制Xoo生长的效果,粗提物对Xoo的最低抑菌浓度为8 μg/mL,最低杀灭浓度为32 μg/mL;扫描电镜观察结果显示,粗提物对Xoo细胞有很强的损伤作用;粗提物还能改变Xoo细胞内膜通透性,降低Xoo细胞的疏水性。促生试验结果显示,菌株St-79发酵滤液能够促进水稻幼苗的生长。盆栽试验结果显示,菌株St-79发酵滤液对水稻白叶枯病有良好的防治效果,在日本晴、甬优15、甬优1540上的相对防效为65.95%~87.23%,病斑抑制率为69.85%~95.8%,且预防效果优于治疗效果。【结论】获得一株有效防治水稻白叶枯病的放线菌,其对水稻白叶枯病菌有明显的抑制作用,并且可以促进水稻种子的萌发与幼苗的生长。

关键词: 放线菌, 硫藤黄链霉菌, 水稻白叶枯病菌, 发酵滤液, 生物防治, 促生作用

Abstract:

【Objective】 Rice bacterial blight (RBB) is one of the main bacterial diseases on rice, which seriously hinders rice production. The purpose of this study is to obtain an effective actinomycete against RBB and explore its biocontrol and growth-promoting effects, so as to lay a scientific basis for the development and utilization of biocontrol bacteria.【Method】 Actinomycetes against Xanthomonas oryzae pv. oryzae (Xoo) were screened by gradient dilution coating method, co-culture method and Oxford cup method. They were classified and identified by morphological traits, physiological and biochemical reactions, 16S rDNA sequences and phylogenetic-tree analysis. The antimicrobial spectrum of the target strain was analyzed by co-culture method. Antibacterial effect of the target strain was studied by 96-well microdilution method, scanning electron microscope and microbial adhesion hydrocarbon method; The promoting effect of fermentation liquid on rice growth was explored by soaking seeds and spraying soil. The control effect of fermentation liquid of the target strain on rice bacterial blight was studied in a pot experiment.【Result】 A total of 140 actinomycetes strains were isolated from soil in different habitats, and one actinomycete strain St-79 with the strongest antagonistic activity against Xoo was finally screened. The diameter of inhibition zone of fermentation liquid was 64 mm, and it was identified as Streptomyces thioluteus. The strain St-79 had antagonistic effects against Xanthomonas oryzae pv. oryzicola, Xanthomonas axonopodis pv. glycines, Xanthomonas campestris pv. campestris and Pseudomonas syringae pv. tomato. The ethyl acetate crude extract had good inhibitory effect on the growth of Xoo. The minimum inhibitory concentration of crude extract on Xoo was 8 μg/mL, and the minimum bactericidal concentration was 32 μg/mL. The observation results under a scanning electron microscopy showed that the crude extract had a strong damage effect on Xoo cells. Crude extracts can also change the permeability of Xoo cells and reduce the hydrophobicity of Xoo cells. The results of growth-promoting test showed that the fermentation liquid of St-79 could promote the growth of rice seedlings. The pot experiment results showed that the fermentation liquid of St-79 had good control effect on RBB. The relative control efficacies on Nipponbare, Yongyou 15 and Yongyou 1540 was 65.95%-87.23%, and the lesion inhibition rate were 69.85%-95.8%. The prevention effect was better than the post-disease treatment.【Conclusion】 An effective actinomycete against RBB was obtained, which had obvious inhibitory effect on RBB and could promote the germination and seedling growth of rice.

Key words: actinomycetes, Streptomyces thioluteus, Xanthomonas oryzae pv. oryzae, fermentation liquid, biocontrol, promoting growth