Question

Microbes can be used to decrease the use of chemical fertilizers and pesticides. Explain how this can be accomplished.

Answer 1

Microbes can be used to decrease the use of chemical fertilizers and pesticides through the use of biofertilizers. Biofertilizers are living organisms that help to increase the fertility of the soil. Biofretilizers mainly include bacteria, fungi and cyanobacteria. They are added to the seeds, roots and soil inorder to increase the availability of nutrients. Rhizobium is a symbiotic bacteria that is found in the root nodules of leguminous plants. It has the ability to fix free atmospheric nitrogen and increasing the nitrogen content of the soil. Examples of free living bacteria that can fix atmospheric nitrogen are Azotobacter and Azospirillum. Cyanobacteria such as Nostoc and Anabaena also fix atmospheric nitrogen. Mycorhizzae which are symbiotic association of fungi with plants also help in increasing the fertility of soil.

Microbes can also be used to control insects in plants. An example of biopesticide is Bacillus thuiringiensis. It produces a toxin that kills the insects on cotton plants. Tricoderma is a fungi that can be used as a biopesticide. Another example is baculovirus.