Theory:

Economic importance of pteridophytes:
1. As food:
  
Similar to other plants, pteridophytes also constitute a good source of food for animals. The sporocarp of Marsilea, a water fern, is used as food by some people.
 
2. As medicines:
  
The rhizome and petioles of Dryopteris yield is used as a vermifuge drug.
 
3. In nitrogen fixation:
  
Azolla (a water fern) forms a symbiotic association with cyanobacterium and helps in the fixation of bacteria.
 
4. As ornamentals:
  
The ferns are used as ornamental plants (mainly their leaves).
 
5. In soil binding:
  
Through their growth, pteridophytes bind soil even along hill slopes, thereby preventing soil erosion.
Difference between bryophytes and pteridophytes:
Bryophytes
Pteridophytes
The plant body is a thalloid as it cannot be differentiated into root, stem and leaf.The plant body can be differentiated into root, stem and leaf.
These plants live in both plant and water. hence, they are known as amphibians of the plant kingdom.The pteridophytes are true land plants.
The vascular tissues such as xylem and phloem are absent in these plants.The vascular tissues such as xylem and phloem are present in these plants.
The gametophytic phase is dominant in these plants.The sporophytic phase is dominant in these plants.
The sporophytic phase of these plants is completely dependent on the gametophytic generations.In these plants, the gametophytic generation is independent.
Example: Riccia, Funaria and anthoceros.Example: Selaginella, Psilotum and Lycopodium