Answer: Through mycoparasitism, antibiosis, competition for nutrients and space, and induced systemic resistance.
- A Mainly through the production of antibiotic compounds released continuously into the surrounding soil environment
- B Through mycoparasitism, antibiosis, competition for nutrients and space, and induced systemic resistance
- C Mainly by outcompeting pathogens for available physical space within the surrounding soil matrix
- D Through secretion of broad-spectrum toxins that indiscriminately kill all other soil microbes present nearby
Correct answer: B. Through mycoparasitism, antibiosis, competition for nutrients and space, and induced systemic resistance
Explanation: Trichoderma species employ multiple biocontrol mechanisms including mycoparasitism (directly attacking pathogenic fungi), antibiosis (producing antifungal metabolites), competition for nutrients and space, and inducing systemic resistance in host plants.
Sewage passes through physical removal (primary), then aerobic biological treatment where microbes form flocs that consume organic matter (secondary); the settled activated sludge is then digested anaerobically to produce biogas - a deliberate switch from aerobic to anaerobic conditions between stages.
Concept context
Microorganisms in food, medicine, sewage treatment, biocontrol, and biofertilizers