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A pteridophyte which fixes nitrogen is

A pteridophyte which fixes nitrogen is Correct Answer Azolla

Concept:

  • Pteridophyta: Plants from this group have well-developed roots, stem and leaves, and separate tissues for conduction of food and water. But, they do not bear flowers and fruits.

Explanation:

  • Azolla is a free-floating aquatic fern (pteridophyte).
  • There are six species of Azolla – Azolla Carolina, Azolla nilotica, Azolla filiculoids, Azolla Mexicana, Azolla microphylla and Azolla pinnata.
  • They are extremely reduced in form and specialized, looking nothing like the typical fern but more resembling duckweed or some mosses.
  • Under optimal conditions, they form a symbiotic relationship between the cyanobacterium Anabaena azollae and fix a substantial amount of nitrogen
  • Due to their ability to fix nitrogen, they are widely used as a bio-fertilizer to improve soil fertility and boosting crop yields.
  • Azolla pinnata serves as a great biofertilizer for paddy crops (rice). It increases the nutrient uptake and grain yield of rice.

Additional Information

  • Pteris belongs to the class pteropsida of the phylum Pteridophyta. It is a homosporous pteridophyte
  • Selaginella:  Also called Little club moss or spike moss or Bird’s nest moss.
  • Most of the species of selaginella are ‘’Drought Escapers’’, so they are called Resurrection plants.
  • Salvinia is a free-floating fern belonging to the family Salviniaceae. It is a heterosporous pteridophyte producing two different types of spores microspores & megaspores

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The passage best supports the statement that:
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