Question

Explain a few biological methods to control the pest population.

Answer 1

Biological control uses natural predators, parasites or disease-causing microbes to keep pests at manageable levels.

1. Predators: Ladybird beetles feed on aphids, while dragonflies help control mosquitoes.
2. Bt bacteria: Bacillus thuringiensis produces a protein toxic to certain insect larvae. When caterpillars eat treated leaves, the toxin is released in their gut and kills them.
3. Trichoderma: These free-living fungi in root ecosystems act as biocontrol agents against several plant pathogens.
4. Baculoviruses: Certain baculoviruses, including Nucleopolyhedrovirus, target particular insect pests and have little effect on plants, vertebrates and many beneficial insects.
5. Crop-management methods: Crop rotation, mixed planting, sanitation and planting a pest-preferred trap crop away from the main crop can also reduce pest populations.

These methods form part of Integrated Pest Management, which aims to control pests without unnecessarily disrupting the ecosystem.