What is a primary characteristic of Bti as a microbial insecticide?

Bti, or Bacillus thuringiensis israelensis, is a microbial insecticide specifically used for controlling mosquito populations. Its primary characteristic is its ability to target the larvae of mosquitoes and some other specific aquatic dipterans, such as black flies. When larvae ingest Bti, it produces proteins that are toxic to them, leading to their death.

The specificity of Bti for mosquito larvae means it effectively reduces mosquito populations without impacting most other non-target organisms, including beneficial insects and other wildlife. This selectivity is a significant advantage in integrated pest management, as it minimizes harm to the ecosystem while effectively controlling pests.

The other responses inaccurately describe Bti's action; for example, Bti does not target ants or all flying insects, which are not within its spectrum of action. Its design as an insecticide provides a focused approach to managing specific pests while preserving ecological balance.