Cassava is a major food crop in a country. A new fungal disease spreads through two cassava-growing regions.
| Region | Cassava plants grown | Yield before the disease in tonnes per hectare | Yield after the disease in tonnes per hectare |
|---|---|---|---|
| A | Clones of one variety | 20.0 | 6.0 |
| B | Four genetically different varieties | 18.0 | 13.5 |
Calculate the percentage decrease in the yield in Region A.
Explain why the disease is a greater threat to food security in Region A than in Region B. Use the information in the table.
127 exam-style questions on OCR GCSE Biology 6.2 Feeding the human race, covering 6.2.1 Biological factors affecting food security, 6.2.2 Agricultural solutions to growing demand, 6.2.3 Selective breeding, 6.2.4 Genetic engineering, 6.2.5 Steps in genetic engineering, 6.2.6 Benefits and risks of gene technology in agriculture, and 6.2.7 Biotechnological solutions to growing demand. Each one has a worked solution and a mark scheme showing where the marks go.