Evaluation of Antagonists to Manage Soil Borne Pathogens for Soil Health

Overview

This research focuses on identifying and evaluating antagonistic microorganisms to combat soil borne pathogens that threaten vegetable crops in Myanmar and globally. Fusarium wilt (caused by Fusarium oxysporum) and bacterial wilt (caused by Ralstonia solanacearum) are persistent soil borne diseases that are difficult to eliminate because the pathogens remain dominant in soil over extended periods. Current disease management relies heavily on chemical pesticides, which raises concerns about soil health and sustainability. This project seeks to isolate beneficial fungi and bacteria from infected tomato fields and screen them for their ability to suppress these pathogens, ultimately developing microbial biocontrol agents as a more sustainable alternative.

Technical specifications

Research approach and methodology:

• Isolation of potential antagonistic fungi and bacteria from soil naturally infected with Fusarium wilt and bacterial wilt in cultivated tomato fields
• In vitro screening using selective media to identify the most effective antagonists against Fusarium oxysporum and Ralstonia solanacearum
• Dual culture techniques to evaluate antagonistic activity and confirm pathogen suppression
• Morphological and biochemical characterization of candidate antagonists
• Rep-PCR detection to investigate genetic variations among isolates
• Molecular gene sequencing for definitive identification of effective antagonists
• Phytotoxicity testing on susceptible host plants to confirm safety
• In vivo validation on susceptible tomato varieties under field conditions to confirm efficacy as a microbial pesticide

Target antagonistic organisms:

• Bacillus spp. (beneficial bacteria)
• Pseudomonas spp. (beneficial bacteria)
• Trichoderma spp. (beneficial fungi)

Technology readiness level

This project is at an early-to-mid stage of research and development. The initial phases involve laboratory-based isolation and characterization of antagonistic microorganisms, followed by controlled in vitro screening. Future validation steps include comprehensive morphological, biochemical, and molecular characterization, phytotoxicity assessment, and in vivo field trials on susceptible tomato varieties. The ultimate goal is to confirm and recommend an effective bio-pesticide formulation for managing soil borne pathogens and improving soil health in vegetable production systems.