Class 12th Biology 2016 Set1 Outside Delhi Board Paper Solution
Question 17
How do organic farmers control pests ? Give two examples.
Answer
Organic farmers create a system where the insects are not eradicated, but are kept at manageable levels by a complex system within living and vibrant ecosystem.
Examples are :
(i) The ladybird and dragon flies are useful to get rid of aphids and mosquitoes respectively.
(ii) Bacillus thuringiensis (Bt) are used to control butterfly caterpillars.
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