ISSN 2736-1756
Advanced Journal of Microbiology Research ISSN 2241-9837 Vol. 13 (1), pp. 001-006, January, 2019. © International Scholars Journals
Full Length Research Paper
Isolation and identification of endophytic bacterium W4 against tomato Botrytis cinerea and antagonistic activity stability
Cong-Jun Yang1,2, Xin-Gang Zhang1,2, Guan-Ying Shi1,2, Hao-Yu Zhao1,2, Long Chen1,2, Ke Tao1,2* and Tai-Ping Hou1,2*
1College of Life Sciences, Sichuan University, Chengdu 610064, China.
2Key Laboratory of Bio-resources and Eco-environment, Ministry of Education, Sichuan University, Chengdu 610064, China.
Accepted 21 December, 2018
Abstract
Of the 72 endophytic bacteria isolated from healthy tomato stems and leaves from field-grown plants, the strain W4 gave strongly inhibitory effect on Botrytis cinerea Pers, with the inhibition rate 78% in dual culture assay and 100% using fermentation filtrate diluted 20 times. Based on morphological, physiological and biochemical properties, 16S rDNA gene sequences and Biolog system analysis, the isolate W4 was identified and named as Brevibacillus brevis W4. The activity determination demonstrated that the antagonistic effect of W4 fermentation filtrate on B. cinerea was fairly stable to temperature, pH, ultraviolet light. Only heated at 90°C for 30 min or at 100°C or above for 10 min, the inhibitory effect was significantly reduced. The inhibitory rate remained above 90% at pH 2-11 and above 95% under ultraviolet light radiation for 5-240 min. These stability characteristics of antagonistic activity were conducive to future applications in the field.
Key words: Botrytis cinerea, Brevibacillus brevis W4, endophytic bacteria, antagonistic activity.