A pesticide is any substance or mixture of substances intended for defoliating or desiccating plants, preventing fruit drop, inhibiting sprouting, or for preventing, destroying, repelling, or mitigating any insects, rodents, fungi, bacteria, weeds, or other forms of plant or animal life or viruses, except viruses on or in living man or other animals. (Clemson University, 2014)
"Biopesticides are certain types of pesticides derived from such natural materials as animals, plants, bacteria, and certain minerals. For example, canola oil and baking soda have pesticidal applications and are considered biopesticides. As of April 2016, there are 299 registered biopesticide active ingredients and 1401 active biopesticide product registrations."
Biochemical insecticides are naturally occurring compounds or synthetically derived compounds that are structurally similar (and functionally identical) to their naturally occurring counterparts. In general, these insecticides are characterized by a non-toxic mode of action that may affect the growth and development of a pest, its ability to reproduce, or pest ecology.
Biochemical fungicides derived from plant extracts are also known as botanical fungicides. Botanical fungicides are naturally occurring chemicals extracted from plants. Biochemical fungicides often overlap with biochemical insecticides. The modes of action often have synergistic capabilities so a fungicide can also act as an insecticide.
Microbial insecticides battle damaging insects by enlisting the aid of microscopic, living organisms—viruses, bacteria, fungi, protozoa, or nematodes. Most microbial insecticides are toxic to a single species or group of insects, so you can often target a pest without the risk of killing beneficial insects in the process. Also, most microbial insecticides can be used in conjunction with conventional insecticides.
Recently, numerous antifungal compounds were discovered from diverse microbial sources using traditional activity-based screening techniques. These microbial compounds showed potent control efficacy against various plant diseases, including chronic diseases which are difficult to control with conventional synthetic fungicides. Advances in screening systems directed to specific targets of fungal metabolism have increased the opportunities to discover novel antifungal agents with selectivity over non-target organisms. Microbial metabolites have also been exploited as a source for non-fungicidal disease control agents that do not inhibit vegetative hyphal growth, but rather interfere specifically with the infection process of pathogenic fungi. The specificity of microbial fungicides is a highly preferred characteristic in terms of impacting the environment, where it is closely related to the occurrence of fungicide resistance.
FUNGICIDES AND BACTERICIDES
Fungicides and bactericides prevent or mitigate damage caused by fungi and bacteria to living organisms such as people, animals, plants including agricultural crops, as well as physical structures such as buildings and plant products (e.g., wood). They are developed from natural sources or are chemically synthesized. (UC DAVIS, 2012)
Clemson University. “Definition of Pesticide : Extension : Clemson University : South Carolina.” Clemson University Cooperative Extension, (2014).