Question
What do you understand by biological control? How do micro-organisms act as biological control agents ?

Answer

Biological Control: It refers to the use of biological methods for controlling plant diseases and pests instead of using chemicals like insecticides and pesticides.
How Micro-organisms act as Biological Control Agents:
Bacillus thuringiensis (Bt): It is used to control butterfly caterpillars. The spores are mixed with water and sprayed onto plants. When larvae eat these, the toxin is released in their gut, killing them.
2. Trichoderma: These are free-living fungi found in the root ecosystems. They are very effective biocontrol agents against several soil-borne plant pathogens.
3. Baculoviruses (Nucleopolyhedrovirus): These viruses attack insects and other arthropods. They are species-specific and have a narrow spectrum, meaning they do not harm non-target organisms like plants, birds, or mammals.

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