Microbes are useful as
A. Biocontrol agents
B. Biofertilizers preparation
C. Biogas production
D. Fermentation
Choose the correct answer from the options given below:
Concept:
Microorganisms, including bacteria, fungi, actinomycetes, and viruses, play diverse, indispensable roles in agricultural ecosystems, bioenergy generation, and industrial biotechnological processes.
Rather than being solely pathogenic, many microbial species are deliberately cultured and utilized to replace harmful chemicals, generate renewable energy, and improve soil fertility.
Evaluating each application helps assess their widespread utility in modern agriculture and allied sectors. Step 1: Role as Biocontrol Agents (A):
Microbes serve as effective biological control agents against insect pests and phytopathogens.
Examples include Bacillus thuringiensis (Bt) for controlling lepidopteran pests, the fungus Trichoderma viride for suppressing root rot pathogens, and Baculoviruses (NPV) for targeted pest management. Step 2: Role in Biofertilizers Preparation (B):
Microorganisms improve plant nutrient availability naturally.
Symbiotic bacteria like Rhizobium, free-living fixers like Azotobacter, associative fixers like Azospirillum, and phosphorus-solubilizing microorganisms ($\text{PSM}$) are formulated into biofertilizers. Step 3: Role in Biogas Production (C):
Methanogenic archaebacteria (e.g., Methanobacterium) break down animal dung and lignocellulosic crop wastes anaerobically in biogas plants to generate methane and carbon dioxide fuel. Step 4: Role in Fermentation (D):
Microbes drive anaerobic and aerobic fermentation pathways.
Saccharomyces cerevisiae (yeast) is widely used in baking and ethanol production, while lactic acid bacteria ($\text{LAB}$) are essential in dairy processing and silage making. Step 5: Final Answer:
Since all four statements A, B, C, and D are valid and well-established uses of microbes, option (C) is correct.
