Vascular Non-Seed Plants

• Tracheophytes


  Vascular plants
• Apomorphies of Tracheophytes


  • Sporophyte independent, long-lived
  • Sporophyte branched, with multiple sporangia
  • Lignin, in lignified secondary cell walls
  • Sclerenchyma
  • Vascular tissue
  • Endodermis
  • Roots
• Tracheophytes


  • Sporophyte is the dominant, long-lived, obvious entity
  • Gametophyte now depends on the sporophyte
• Sister taxa of Tracheophytes

  • Lycophytes (fern allies)
  • Euphyllophytes [Monilophytes (true ferns); Lignophytes]
• Sporophyte


  • In non-vascular plants/bryophytes, the gametophyte body is the more visible, dominant and long-lived entity
  • In vascular plants, the sporophyte is the dominant, long-lived, obvious entity
• Sporophytic axes of vascular plants

  • Branched and bear multiple sporangia
• Evolution of branching in earliest vascular plants

  1. Dichotomous branching

  2. Pseudomonopodial growth (one branch becomes dominant)
• Lignified Secondary Cell Wall

  • Additional cell wall between primary cell wall and plasma membrane in some plant cells
  • Provides structural support
• Lignin


  • Complex polymer of phenolic compounds
  • Imparts strength and rigidity to cell wall
• Sclerenchyma


  • Secondary cell wall in addition to primary cell wall
  • Usually dead at maturity
  • Fibers and sclereids
• Vascular Tissues


  • Tracheary elements of xylem: Tracheids and Vessel members
  • Sieve elements of phloem: Sieve cells and Sieve tube members
• Endodermis


  • Single layer of cells surrounding roots and underground stems
  • Casparian strip - band of lignin/suberin that forces water/minerals to flow through plasma membrane
• Roots


  • Found in all vascular plants except Psilotales, Salviniales and few other specialized roots