Vijai Malik*
Department of Botany, CCS University, Meerut
Email: gathwalajai@gmail.com
Received-04.12.2019, Revised-26.12.2019
Abstracts: Angiosperms (Magnoliophyta or Anthophyta), Cycads (Cycadophyta), Conifers (Coniferophyta), Gnetophytes or Gnetales (Gnetophyta) and Ginkgo (Ginkgophyta) are the five major lineages of the extant seed plant. Of these Angiosperms are the most species rich and include more than 13000 genera and 300000 species. The Conifers are second largest group of seed plants with ca. 70 genera and 600 species. The cycads include ca. 9 genera and 129 species. Gnetales include only 3 genera (Gnetum, Ephedra and Welwitschia) with 90 species. There is single species of Ginkgo biloba. Caytoniales, Bennettiales, Pentoxylon, Corystosperms and Glossopterids, are the extinct lineages of seed plants. These have been proposed as putative relative and possible progenitors of the Angiosperms (Soltis et al., 2005).
Keywords: Angiosperms, Cradle, Flowering plants, Seed
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