Another product that is new on the market is Beauveria bassiana JW1. It controls insects such as aphids, thrips, mites, whiteflies, and leaf-feeding caterpillars on a variety of indoor and outdoor ornamental plants, trees, and shrubs. It is not labeled for food crops. Naturalis-O. Protozoa are pathogens that sometimes kill their insect hosts, but more often weaken them, causing them to produce fewer offspring. Few protozoan pathogens seem to be suited for development as insecticides.
Viruses are very specific diseases which usually act against only a single insect genus or species.
Viruses, like bacteria, must be eaten by the insect to be effective. This is another category of biologicals under development, and uses as an insecticide have been limited. Insect viruses must be produced in live host insects, which is expensive and time-consuming. Since viruses are host-specific, each viral insecticide has a limited market. Many viruses have also proven to be less effective than available synthetic insecticides.