Question

Organic produce has become popular with the public in recent times. A farmer wants to use organic substitutes instead of chemical pesticides in his farm. Why would he want to do so? Suggest some some ways he can do so. [5]

Answer 1

The organic farmer believes that pests should not be eradicated as without them, the beneficial predatory and parasitic insects which depend upon them as food or hosts would not be able to survive. [1]

Some ways this can be done is as follows:

1. Ladybirds and dragonflies are useful to get rid of aphids and mosquitoes. [1]
2. Spores of bacteria Bacillus thuringiensis can be sprayed onto vulenerable plants. When a caterpillar ingests it, the toxin is released in its gut and the larvae gets killed. The bacterial disease will kill the caterpillars, but leave other insects unharmed. [1]
3. Trichoderma is a fungus which can be used as a treatment for several plant diseases. [1]
4. Nucleopolyhedrovirus have narrow spectrum insecticidal properties. They have shown no negative effect on non-target organisms. [1]