Biofertilisers are the organisms that enrich the nutrient quality of the soil. Which of the following is not a source of biofertiliser ?

Baculoviruses

The correct answer is Option (3) -Baculoviruses

Biofertilizers are living organisms that enhance the nutrient quality of the soil. They primarily derive from three sources: bacteria, fungi, and cyanobacteria.

One prominent example of biofertilizers is the nodules found on the roots of leguminous plants. These nodules are formed through a mutually beneficial association with bacteria known as Rhizobium. Rhizobium bacteria have the remarkable ability to convert atmospheric nitrogen into organic forms that serve as nutrients for the plant.

In addition to Rhizobium, there are other bacteria like Azospirillum and Azotobacter that can independently fix atmospheric nitrogen while existing freely in the soil. This process contributes to the enrichment of nitrogen content in the soil.

Fungi also play a crucial role in forming symbiotic associations with plants, a relationship known as mycorrhiza. These fungi assist plants in nutrient absorption.

Cyanobacteria, which are autotrophic microorganisms, are widely distributed in both aquatic and terrestrial environments. Many of them possess the capability to fix atmospheric nitrogen. Examples of such nitrogen-fixing cyanobacteria include Anabaena, Nostoc, and Oscillatoria.

Overall, biofertilizers are valuable in promoting soil fertility and enhancing plant growth by facilitating nutrient uptake from the environment.

Baculoviruses are pathogens that attack insects and other arthropods. The majority of baculoviruses used as biological control agents are in the genus Nucleopolyhedrovirus. These viruses are excellent candidates for species-specific, narrow spectrum insecticidal applications.