Question

Name the bacterium that is first used as biopesticide.

Answer 1

Hint: Bacteria are single-celled unicellular organisms and are classified under the domain Prokaryote because they lack membrane-bound organelles like those found in eukaryotes. Although they are all microscopic organisms and cannot be seen with naked eyes that can be found in various environments in nature, bacteria widely vary in size, shape, and arrangement.

Complete answer:
Bacteria are specialised to perform many functions such as they acts as:-
> Saprophytic bacteria: They are free living bacteria, obtaining nourishment from organic remains such as dead animals, animal excreta, fallen leaves, decaying vegetables, fruits, bread and other products of animal and plant origin. These bacteria secrete digestive enzymes into the substrate and the complex insoluble substances are converted into simple soluble compounds like water, hydrogen sulphide, ammonia, $\mathop {CO}\nolimits_2 $, etc. Some of the simple substances are absorbed and accumulated by the bacteria, whereas the others are added to the soil and atmosphere to complete nature's material cycle.
> Symbiotic bacteria: They are mainly Gram negative types. A familiar example of symbiotic bacteria is Rhizobium leguminosarum, associated with roots of leguminous plants. They are capable of fixing atmospheric nitrogen as ammonia, inside the nodule only and not in free state. However, some
bacteria like Azotobacter, Beijerinckia, Klebsiella are free living, aerobic and capable of nitrogen fixation in free state, enriching the soil. Clostridium is anaerobic $\mathop N\nolimits_2 $, fixing bacteria.
> Parasitic bacteria: These bacteria draw nourishment and obtain special organic compounds required for growth from living organisms, either plants or animals, called hosts. The disease bacteria which causes disease are termed pathogenic and the ones not causing any disease are termed as non-pathogenic.
> Biopesticide bacteria: Biopesticides are substances that are used to increase soil fertility and to increase crop production but they are produced from natural resources such as plants and animals . The first bacteria to be used as biopesticide is Bacillus thuringiensis.

So, our required answer is Bacillus thuringiensis.

Note:
Bacillus thuringiensis, is a bacteria that is capable of causing disease of Lepidoptera, Coleoptera and Diptera is a well-known insecticide example. The toxin from B. thuringiensis (Bt toxin) has been incorporated directly into plants mostly in cotton through the use of genetic engineering.