Evaluation of the combination of Bacillus velezensis JPS19 and Bacillus thuringiensis E13 in the control of tomato root and crown rot

Document Type : Research Paper

Authors

Department of Phytomedicine, Faculty of Agriculture, University of Tehran, Karaj, Iran.

10.22059/ijpps.2025.397451.1007082

Abstract

Tomato root and crown rot, caused by the soil-borne pathogen Fusarium oxysporum f. sp. radicis-lycopersici (FORL), is a major disease and a leading cause of significant yield loss in tomato production worldwide. The use of soil-borne antagonists to improve crop performance and protect plants is a highly promising approach in modern sustainable agriculture. This study investigated the in vitro antagonistic effects of a bacterial combination on the pathogen’s mycelial growth. Two strains, Bacillus thuringiensis E13 and Bacillus velezensis JPS19, were found to effectively form an inhibition zone against the growth of the FORL pathogen. To evaluate their potential to reduce disease severity and suppress the pathogen, a greenhouse experiment was conducted with various treatments. These included separate inoculations with the two bacterial strains, pathogen-only inoculation, and a combined application of both bacterial strains. The results showed a dramatic reduction in disease severity. While the inoculated control group showed a high disease severity of 73.33%, the application of the two bacterial strains reduced this to just 6.66%. A suspension containing 10⁹ colony-forming units (CFU) of the combined bacterial strains was used to assess their impact on pathogen growth and plant health. The combination of Bacillus velezensis JPS19 and Bacillus thuringiensis E13 led to an 8.83% improvement in tomato plant growth compared to the healthy control. Furthermore, this treatment significantly increased the fresh weight of both the roots and shoots of the treated plants when compared to the infected plants.

Keywords



Articles in Press, Accepted Manuscript
Available Online from 27 September 2025
  • Receive Date: 28 June 2025
  • Revise Date: 30 August 2025
  • Accept Date: 27 September 2025