Which one of the following proved effective for biological control of nematodal diseases in plants?

Which virus is used as a biocontrol agent?

Which of the following statements regarding baculoviruses as biocontrol agents is/are correct?
$I.$ Baculoviruses are pathogens that attack insects and other arthropods.
$II.$ Most of these biocontrol agents belong to the genus $Nucleopolyhedrovirus$.
$III.$ They do not harm plants,mammals,birds,fish,and other non-target insects.
$IV.$ Baculoviruses are helpful in Integrated Pest Management $(IPM)$ programmes,in which beneficial insects are conserved.
Choose the correct option.

Identify the incorrect statement.
$(i)$ Bacillus thuringiensis are available in sachets as dried spores which are mixed with kerosene and sprayed on to vulnerable plants.
$(ii)$ $B. thuringiensis$ are used to control butterfly caterpillars,but leave other insects unharmed.
$(iii)$ The toxin of $B. thuringiensis$ is released in the blood of larvae and the larvae get killed.
$(iv)$ By the development of methods of genetic engineering,$B. thuringiensis$ toxin genes have been introduced into plants.

The concept of sustainable agriculture lies in:

'Rotenone' is