Can A Combination Of Trichoderma Harzianum And Bacillus Subtilis As Biological Control Agents Suppress The Severity Of Fusarium Oxysporum F. Sp. Cannabis In Hemp Plants Grown In A Greenhouse Setting With A CO2 Supplementation Rate Of 800 Ppm And A Temperature Fluctuation Of ± 5°C?

by ADMIN 282 views

The combination of Trichoderma harzianum and Bacillus subtilis can effectively suppress Fusarium oxysporum f. sp. cannabis in hemp plants grown in a greenhouse with 800 ppm CO2 and a temperature fluctuation of ±5°C. Here's a structured summary of the reasoning:

  1. Pathogen and Biocontrol Agents:

    • Fusarium oxysporum is a soilborne pathogen causing wilt in hemp, challenging to eradicate once established.
    • Trichoderma harzianum, a fungus, attacks Fusarium through parasitism and produces antibiotics, enhancing plant health.
    • Bacillus subtilis, a bacterium, produces antibiotics like bacillomycin, competes for resources, and promotes plant growth.

  2. Synergistic Effects:

    • Together, they target Fusarium through different mechanisms, potentially creating a hostile environment for the pathogen.
    • Trichoderma's direct fungal attack complements Bacillus's antibiotic production, enhancing biocontrol efficacy.

  3. Greenhouse Conditions:

    • CO2 at 800 ppm promotes plant growth, likely not harming the biocontrol agents.
    • Temperature fluctuations of ±5°C, if within the optimal range (20-30°C), should not impede their effectiveness.

  4. Application Considerations:

    • Effective application methods include seed treatments, soil drenches, or foliar sprays.
    • Timing is crucial; applying before pathogen presence helps establish the agents.

  5. Soil Microbiome and Concentration:

    • They may outcompete Fusarium, with higher CO2 potentially enhancing microbial activity.
    • Optimal concentration is key to avoid inefficacy or harm.

  6. Potential Issues and Research:

    • Compatibility between agents is important; they likely complement each other without antagonism.
    • Further studies in similar conditions would confirm effectiveness, though existing principles support their use.

In conclusion, the combination of Trichoderma harzianum and Bacillus subtilis is a promising biocontrol strategy against Fusarium wilt in hemp under the specified greenhouse conditions.