We used to learn about this fungi as an alternative to pesticides, especially in organic agriculture.

So, if you have a cultivar that is being attacked by some insects that are vulnerable to that fungi, you can simply introduce that fungi into your cultivar and your plants will be protected with no chemicals added in the process. Really cool stuff. :)

It is called biological methods for plants protection. It is based on using natural nemesis against pests. You can also use another insect that will eat insects that do damage on plants.
Applying natural nemesis isn't easy though... You need to know all biology about pest and about natural nemesis to do it right. But is it a great alternative to conventional pesticides and it is environment-friendly.