生物技术通报 ›› 2022, Vol. 38 ›› Issue (6): 136-146.doi: 10.13560/j.cnki.biotech.bull.1985.2021-1124

• 研究报告 • 上一篇    下一篇

枯草芽孢杆菌K-268的分离鉴定及对水稻稻瘟病的防病效果

祖雪1,2,3(), 周瑚1,2,3, 朱华珺1,2,3, 任佐华1,2,3, 刘二明1,2,3()   

  1. 1.湖南农业大学植物保护学院,长沙 410128
    2.植物病虫害生物学与防控湖南省重点实验室,长沙 410128
    3.南方粮油作物协同创新中心,长沙 410128
  • 收稿日期:2021-09-01 出版日期:2022-06-26 发布日期:2022-07-11
  • 作者简介:祖雪,女,硕士研究生,研究方向:植物病理学;E-mail: 1762823097@qq.com
  • 基金资助:
    国家重点研发计划项目(2016YFD03007700);中央财政专项(2014ZX0800102B);公益性行业(农业)科研专项(201203014);湖南省“十二五”重点学科(0904)

Isolation and Identification of Bacillus subtilis K-268 and Its Biological Control Effect on Rice Blast

ZU Xue1,2,3(), ZHOU Hu1,2,3, ZHU Hua-jun1,2,3, REN Zuo-hua1,2,3, LIU Er-ming1,2,3()   

  1. 1. College of Plant Protection,Hunan Agricultural University,Changsha 410128
    2. Hunan Key Laboratory of Plant Pest Biology and Control,Changsha 410128
    3. Southern Grain and Oil Crop Collaborative Innovation Center,Changsha 410128
  • Received:2021-09-01 Published:2022-06-26 Online:2022-07-11

摘要:

生防细菌是绿色防控稻瘟病的有效措施。为了发掘高效拮抗稻瘟病菌的生防细菌,本研究采用平板对峙法从感病品种K020268的健康稻株叶片中筛选获得1株对稻瘟病菌抑制效果较好的拮抗细菌K-268,同时测定该菌的抑菌谱。通过形态学观察、生理生化鉴定16S rRNA 和gyrA序列分析对其进行菌种鉴定,并初步研究了该菌株的生物学特性和对稻叶瘟的防治效果。结果表明,菌株K-268对稻瘟病菌菌丝生长抑制率为86.30% ± 0.70%,同时对水稻纹枯病菌、玉米大斑病菌及柑橘沙皮病菌等供试的14株植物病原菌均有抑制作用;经鉴定菌株K-268为枯草芽孢杆菌(Bacillus subtilis),该菌株对数生长期为14-32 h,生长最适温度为30℃,生长最适pH值为6.0-7.0,并且其具有良好的耐盐性。离体接种实验结果表明,稀释10倍即菌液浓度6×108 CFU/mL时,预防组和治疗组的叶瘟发病率分别为14.81%和23.46%,效果与稀释750倍的75%三环唑稀释液(WP)效果相当。活体喷雾接种结果表明,在接种稻瘟病菌分生孢子悬浮液(1×106个/mL)前 24 h 喷施稀释10 倍(6×108 CFU/mL)的发酵液和接种稻瘟病菌分生孢子悬浮液后 24 h 喷施稀释10倍的发酵液对稻叶瘟的防效分别为59.00%和60.23%,效果接近500稀释液的40%稻瘟灵(EC)。因此K-268在水稻稻瘟病生物防治中具有一定的开发和应用价值。

关键词: 稻瘟病, 枯草芽孢杆菌, 分离鉴定, 生物防治

Abstract:

The use of biocontrol bacteria is an effective measure for green prevention and control of rice blast. In order to discover biocontrol bacteria with high efficiency against Magnaporthe oryzae,an antagonistic bacterium K-268 with the optimal inhibitory effect on M. oryzae from the healthy rice leaves of the susceptible variety K020268 was obtained by using the plate confrontation method and its antimicrobial spectrum was determined. Using morphological observation,physiological and biochemical identification 16S rRNA and gyrA sequence analysis,the identity of the strain was determined. In addition,the physical characteristics of the strain and its control effect against rice leaf blast were preliminarily studied. Results showed that strain K-268 had inhibitory rate of(86.30 ± 0.70)% on the mycelial growth of M. oryzae,and it demonstrated the inhibitory effects on 14 plant pathogenic fungi,such as Rhizoctonia solan,Exserohilum turcicum and Diaporthe citri,etc. Strain K-268 was identified to be Bacillus subtilis,its logarithmic growth period was 14-32 h,the optimal;growth temperature was 30℃,the optimal pH was 6.0-7.0,and had good salt tolerance. The results from in vitro inoculation experiments showed that the disease rate in the prevention group and the treatment group was14.81% and 23.46%,respectively,when the bacterial solution was diluted by 10 times to 6×108 CFU;and the effect of which was not significantly different from that of the 750 times diluted 75% tricyclazole diluent(WP). Results of in vivo spray inoculation showed that the control effects on the rice leaf blast were 59.00% and 60.23%,respectively,when the 10 times diluted fermentation liquid(6×108CFU/mL)were sprayed 24 h before and after inoculation with Magnaporthe oryzae conidia suspension(1×106 /mL),respectively. These effects were close to the 40% rice blast spirit(EC)with 500 times dilution. Therefore,K-268 was confirmed to have certain development and application value in the biological control of rice blast.

Key words: rice blast, Bacillus subtilis, isolation and identification, biological control