Phylum Gnetophyt

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PHYLUM GNETOPHYTA• This phylum is described as the unusual

gymnosperm. Unusual since the three genera- gnetum, ephedra, and welwitschia- differ significantly from one another in their vegetative and reproductive structures. GNETOPHYTES are semi desert plants. Among the three genera, EPHEDRA is considered the closest to angiosperms since its mode of fertilization closely resembles the flowering plants.

PHYLUM GNETOPHYTA• The Gnetophytes differ from other gymnosperms

(i.e. conifers, cycads and ginkgos)in having a vessel elements (which transport water within the plant) as found in flowering plants. The gnetophytes evolutionary relationships remain unclear: in some classifications, all three genera are placed in a single order (Gnetales), while in other classifications they are distributed among three orders, each containing a single family and genus. Most morphological and molecular studies confirm that Gnetum and Welwitschia diverged from each other more recently than from Ephedra.

PHYLUM GNETOPHYTA“Welwitschia”

Welwitschia is a monotypic gymnosperm genus, comprising solely the very distinct Welwitschia mirabilis.

The plant is commonly known simply as Welwitschia, and has various common names in local languages.

PHYLUM GNETOPHYTA“Gnetum”

Gnetum is a genus of about 30-35 species of gymnosperms, the sole genus in the family Gnetaceae and order Gnetales. They

are tropical evergreen trees, shrubs and lianas. 

PHYLUM GNETOPHYTA

“Ephedra”

Several additional species belonging to the genus Ephedra have traditionally been used for a variety of medicinal purposes, and

are a possible candidate for the Soma plant of Indo-Iranian religion.