Which fish is introduced into ponds to feed on mosquito larvae?

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.

What is the use of biological organisms or products derived from them to control crop pests and diseases called?

What do bionematicides control?

Which bacterium is used to control harmful pests in fruit trees?

$IPM$ stands for: