Explain how microbes are used as …

Biocontrol refers to the use of biological methods for controlling plant diseases and pests.

Chemicals, insecticides and pesticides are extremely harmful to human beings and also these pollute our environment.

The use of biocontrol measures will greatly reduce our dependence on toxic chemicals and pesticides.

Biocontrol agents are which are useful in controlling plant diseases and pests are-

• The ladybird, a beetle with red and black markings and dragon flies are useful to get rid of aphids and mosquitoes respectively.

• Bacteria Bacillus thuringiensis (Bt) is used to get rid of butterfly caterpillars where dried spores of Bacillus thuringiensis are mixed with water and sprayed onto vulnerable plants such as brassicas and fruit trees and these are eaten by the insect larvae and in the gut of the larvae, the toxin is released and the larvae get killed.
• Trichoderma species are free-living fungi found in the root ecosystem these are effective as biocontrol agents of several plant pathogens.
• Baculoviruses are pathogens that attack insects and other arthropods and the majority of baculoviruses used as biological control agents are in the genus Nucleopolyhedrovirus.