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Question
Organic farmers prefer biological control of diseases and pests to the use of chemicals for the same purpose. Justify.
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Solution
Biocontrol means using biological methods to manage plant diseases and pests. Pathogens, pests, and weeds are the main threats to agriculture. Traditionally, they are controlled with insecticides and pesticides, but these chemicals are highly toxic and harmful to humans and animals, and they pollute the environment. Therefore, modern agriculture increasingly relies on biological methods to manage them. Different microbes are used as biocides to control microbial pathogens (such as viruses, mycoplasma, bacteria, and fungi), insect pests, nematodes, and weeds.
Examples of biocontrol agents include:
- Bacteria: Bacillus thuringiensis
- Fungi: Trichoderma
- Insects: Ladybird beetles and dragonflies
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