Question

Select the correct group of biocontrol agents.

• A. Nostoc, Azospirillum, Nucleopolyhedrovirus
• B. Bacillus thuringiensis, Azotobacter, Aphids
• C. Trichoderma, Baculovirus, Bacillus thuringiensis
• D. Oscillatoria, Rhizobium, Trichoderma

Answer 1

The correct option is C Trichoderma, Baculovirus, Bacillus thuringiensis

Biological control of pests involves the use of natural predators of a pest species, to keep its growth in check. It does not involve eradication of the entire pest population but aims at keeping the population size at a manageable level to maintain a sustainable ecosystem.

Some examples of biocontrol agents include:

Trichoderma: it is a free-living fungus found in many root ecosystems. It is highly effective in controlling many plant pathogens.

Bacillus thuringiensis: Bt toxin is a crystalline toxic insecticidal protein obtained from the soil bacterium Bacillus thuringiensis. The toxin kills the insect larvae. It will kill the caterpillars, but leave other insects unharmed.

Nucleopolyhedrovirus belongs to the family of baculoviruses (viruses that infect insects) that is used as a virus-based insecticide to protect against insect pests.

Nostoc, Azospirillum, Azotobacter, Oscillatoria and Rhizobium are biofertilizers. Biofertilizers are organisms that enrich the nutrient quality of the soil.

Aphids are small sap-sucking insect pests which damage the crops.