Question
Some microbes act as very good biofertilisers. Explain with the help of three suitable examples.

Answer

  1. Mycorrhizae:
  • The fungus absorbs phosphorus from the soil and passes it to the plant.
  • Plants with mycorrhiza show resistance to root-borne pathogens.
  • They show increased tolerance to salinity and drought.
  • There is an overall increase in plant growth and development.
  1. Anabaena:
  • It is a cyanobacterium that fixes atmospheric nitrogen in the soil; it also adds organic matter to the soil through its photosynthetic activity.
  1. Rhizobium:
  • It forms nodules in the roots of legumes and fixes atmospheric nitrogen in the form of ammonia which the plants use.
  1. Trichoderma:
  • This fungus lives freely in the root ecosystem of many plants. It is used as biocontrol agent against many plant pathogens.

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