What is the main purpose of using microbial insecticides?

The main purpose of using microbial insecticides is to control pest populations through the introduction of diseases that pathogens cause in the insects. This method leverages the natural biological processes of microbes, such as bacteria, fungi, or viruses, which can infect and kill specific insect pests.

Microbial insecticides are particularly beneficial because they are more targeted than traditional chemical insecticides, thus reducing the risk of harming non-target organisms, including beneficial insects, and they often have a lower environmental impact. By exploiting the pathogenic properties of these microbes, they disrupt the lifecycle of the pests, helping to suppress their populations over time rather than providing a quick kill, which aligns with Integrated Pest Management principles.

The other options are less aligned with the primary objectives of microbial insecticides. Enhancing soil nutrient levels is more relevant to fertilizers than insecticides. Creating an immediate pest kill suggests a traditional chemical approach rather than the slower, disease-driven method used by microbial products. Promoting plant growth does not directly relate to the role of microbial insecticides, which focus on pest control rather than plant stimulation.