Question

Which one of the following insecticides is of plant origin?
A. Ecdysone
B. Rotenone
C. Parathion
D. Malathion

Answer 1

Insecticides are the chemical substances used to kill insects which are harming plants or crops. Insecticides are one of the major factors to increase agricultural productivity. Insecticides may be repellent or non-repellent. Insecticides are classified on the basis of their structure and mode of action.

Complete answer:
Insecticides can be classified into two major groups:
(A) Systemic Insecticides which can perform long term activity.
(B) Contact Insecticides which have no residual activity.
Now let’s see some insecticides

1. Ecdysone:
   Ecdysone is the major steroid harmane in insects and plays an important role in coordinating developmental transitions such as larval molting and metamorphosis.
   The action of ecdysone is primarily mediated by ecdysone receptor(ECRs)
2. Rotenone:
   It is the natural compound used in creating insecticides and some herbicides. Rotenone is extracted from roots of lonchocarpus species Rotenone is used in home gardening for insect control.
3. Parathion:
   Parathion is also known as diethyl parathion. It is an insecticide which was originally developed by IG Farben in 1940. Which is one of the most toxic to non-target organisms even to humans. So it is restricted to use.
4. Malathion:
   Malathion is also a manmade organophosphate insecticide that is used to control mosquitoes and a variety of insects that attack on fruits, vegetables and shrubs.

Hence, the correct answer is option (B)

Note: Rotenone is extracted from the roots of several tropical plants e.g. derris, which is poisonous to fish but is low toxic to warm-blooded animals.