Characteristics of Pteridophytes and its’ similarities with Bryophytes and Gymnosperms

• Truly land plant with a well-developed vascular system.
• Also called vascular cryptogams.
• Sporophyte is the main plant body which reproduces by the spores.
• It has been derived from a Greek origin (Pteron-Feather and phyton-plant i.e. plants with feather like leaves).
• Their leaves are called fronds.
• Assemblage of seedless vascular plants that have successfully invaded the land habitat and reproduce by means of spores is called pteridophyta.

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Characteristics

• Lycopodium, Selaginella, Dryopteris, Pteridium, etc are the living vascular plants and Rhynia, Hornea, Asteroxylon, etc are fossil vascular plants.
• All living members are herbaceous except a few woody tree ferns.
• True land plant with a well-developed vascular system.
• Plant body is sporophytic, differentiated into root, stem and leaves.
• Simple, small and sessile leaves in Lycopodium, Selaginella, Equisetum, etc or very large and petiolate as in ferns.

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• Sporophytic plant body reproduces by the spores. The spores are formed in sporangia.
• They are both homosporous and heterosporous.
• The sporangia bearing sporophylls are similar to foliage leaves in some cases and are not organized into strobilus or cone while in in others the sporophylls organized into compact strobilus or cone.
• The sporangia develop within specialized structures called sporocarps in aquatic forms like Azolla, Salvinia and Marsilea. In higher ferns the sporangia develop in well-organized groups known as sori.
• The spore on germination gives rise to gametophytic phase, the prothallus.
• Prothalli are usually green, simple or branched and aerial structures, while in some cases such as Lycopodium, they are subterranean, tuberous, colourless and
• The sex organs, antheridia and archegonia develop on the prothallus.
• Fertilization takes place with the help of water.
• The antherozoid and egg fuse to form a diploid oospore. The oospore is the first cell of sporophytic generation.
• Distinct alternation of generations is present in the life cycle.

                                                                                                                               Lycopodium

Similarities with Bryophytes

• Water is essential at the time of fertilization.
• Presence of sterile jacket around the sex organs.
• Formation of the spores.
• Alternation of generation.
• Dependence of the young sporophyte on gametophyte.
• Certain pteridophytes like Rhynia and Psilotum have rhizoids like bryophytes.

Similarities with Gymnosperms

• Sporophytic plant body and differentiation of sporophytes into root, stem and leaves.
• Presence of well-developed vascular tissues.
• Leaves have circinate venation like gymnosperms.
• Xylem lacks vessels and phloem lacks companion cells in both cases.
• Some pteridophytes and all gymnosperms are heterosporous.
• Like gymnosperms, the megaspore is retained in the megasporangium after fertilization in many pteridophytes.
• Mega and microsporophylls form compact strobili in all gymnosperms and in most pteridophytes.

References: 

i) https://study.com/learn/lesson/pteridophyte-characteristics-examples.html

ii) https://www.differencebetween.com/difference-between-bryophytes-and-vs-pteridophytes-and-vs-gymnosperms/

Characteristics of Pteridophytes and its’ similarities with Bryophytes and Gymnosperms