Bt, Fungi and Biologically Derived Products Bt is the most widely used biological insecticide. It's very important to realize that the impression about Bt is that there is no significant gap between classical Bt and genetically engineered Bt, and that it is slow in killing the insect. However, Bt technology has been developed to the point that it's being used correctly in insect control programs. As a result, Bt is capable of protecting crops from insect damage. Certainly the introduction of Bt transgenic plants will have an impact on the market share of Bt sprays, especially in the cotton market.
Fungi are potential bioinsecticides.
This line of products, in the opinion of many people, are chemicals, not biologicals. Product characteristics are identical to chemical insecticides. A pathogenic bacterium lives in the gut of these nematodes. The infective stage enters the insect through its natural opening, releases the bacteria which multiply and, as a result, insect mortality occurs within 48 hours. The nematode develops inside the dead insect and emerges as J3 into the environment seeking other insects.