Intensive Farming - Pest Control
Biology: Edexcel IGCSE, topic 6.1.3
Pest control
Pests can significantly reduce crop yield. They can eat vital parts of plants, compete with plants for resources or spread disease to a crop. Farmers can use methods to reduce the impact of pests on yield.
Pesticides
- Pesticides are chemicals that can be sprayed onto crops to kill insect pests.
- However these chemicals often contain heavy metals that build-up in food chains. They often reach the top apex predators at deadly levels.
Biological control
- Biological control is an alternative method to using pesticides to reduce the impact of pests on crop yield.
- A species that is a predator of the pest is introduced.
- For example, ladybirds are sometimes introduced by farmers into fields or glasshouses to prey on whitefly pests.
- Biological control must be monitored very closely, because introducing a species into a non-native habitat risks it becoming an invasive species.
Test yourself on Intensive Farming - Pest Control
What possible disadvantages are there to using pesticides to increase crop yield?