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Home , Gametophyte, Pteridophyte, Salviniales

10/30/2011

Pteridophyte reproduction

Modified 17-13 (19-9)

Pteridophyta “” To be cont. To Liverworts () Rhynia Lycopodiophyta

microphylls

megaphylls

Transition to land

Microphylls • One vascular trace – No branching vasculature in – Forms from protostele

http://28.media.tumblr.com/tumblr_lgpco8M9Ie1 qa2aauo1_500.jpg

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Megaphylls – Branching vascular traces (veins) in – Typically large

http://intro.bio.umb.edu/111- 112/OLLM/112s99/phyla/plants/pterophyta.jpg

Are not always large.

Highly reduced megaphylls in .

http://www.missouriplants.com/Ferns/E quisetum_hymenale_stems.jpg

Remember the STELES

Pteridophyta

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Stele modification in Pteridophyta

(a few with eustele)

eustele siphonostele

ancestor had protostele, like Lycopodiophyta.

Protosteles Lycopodiophyta

Siphonosteles

Most , though, have siphonosteles with leaf gaps

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Eusteles

Equisetales—eusteles; convergent with .

Modification of cycle and reproduction in Pteridophyta

Heterosporous ferns Filicales

endosporic Eusporangiate ferns

Equisetales leptosporangia

above-ground photosynthetic above-ground photosynthetic gametophyte gametophyte

ancestor had dominant homosporous with underground non-photosynthetic gametophyte, like

Life cycles: above-ground photosynthetic gametophyte

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Modification of life cycle and reproduction in Pteridophyta 2. Leptosporangia

Heterosporous ferns Filicales

endosporic gametophyte heterospory Equisetales

Eusporangiate ferns leptosporangia

above-ground photosynthetic gametophyte

ancestor had dominant homosporous sporophyte with underground non-photosynthetic gametophyte, like Lycopodiaceae

Life cycles: eusporangia vs. leptosporangia

Eusporangia: large 1 to 1000’s of the basal (primitive) condition walls several cells thick found in most land plants

Leptosporangia: small 64 spores walls one cell thick have annulus (thickened ring) grouped into sori (sing. sorus) only in Filicales and heterosporous ferns

Life cycles: eusporangia

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Life cycles: eusporangia in a eusporangiate (Botrychium)

Life cycles: leptosporangia

Life cycles: leptosporangia in Filicales

http://www.google.com/imgres?q=leptosporangia+in+filicales&hl=en&clie http://t0.gstatic.com/images?q=tbn:ANd9GcQ5dCnB8I61yQSkLGFZHRNK9s nt=firefox-a&hs=HLb&sa=X&rls=org.mozilla:en- zAhC4CieR19Yvgi78YQTs01RUurg US:official&biw=748&bih=393&tbm=isch&prmd=imvns&tbnid=cDA5fNilc 4DjaM:&imgrefurl=http://www.increasemyvocabulary.com/definition/of/le ptosporangium/&docid=UL- NACsnDhf5jM&imgurl=http://farm3.static.flickr.com/2127/2263445746_6 1832fff71.jpg&w=500&h=375&ei=-2OsTtbwC62rsALHi8WADw&zoom=1

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Life cycles: leptosporangia grouped into sori in Filicales (Thelypteris)

http://t2.gstatic.com/images?q=tbn:ANd9GcR67ZaOrG_IZnVCT JlKNnzNb9xRzv2WRyzTn65QY9_qNAtdmw-d

Life cycles: leptosporangia grouped into sori in Filicales (Asplenium)

http://t2.gstatic.com/images?q=tbn:ANd9GcRa-R- awiaCHFAk1U2wWgyE4uwVRf-2z5DuiTDyJ5trjRpP7kMP

Modification of life cycle and reproduction in Pteridophyta 3. Heterospory and endosporic

Heterosporous ferns Filicales

endosporic gametophyte heterospory Equisetales

Eusporangiate ferns leptosporangia

above-ground photosynthetic gametophyte

ancestor had dominant homosporous sporophyte with underground non-photosynthetic gametophyte, like Lycopodiaceae

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Life cycles: heterospory

The life cycle of is the same as that found in the heterosporous ferns and in the seed plants.

Embryophytes

Pteridophytes “Bryophytes” To be cont. To Liverworts Hornworts Mosses Rhynia (Fossil) Rhynia Lycopodiophyta

megaphylls

Transition to land

Equisetales: brief overview

--highly reduced megaphylls --eusteles --homosporous --eusporangia --above-ground photosynthetic gametophyte --strobili --hollow, jointed stems embedded with silica --one genus, , about 15 species;

8 10/30/2011

Equisetales: Equisetum

Equisetales is the only fern group with strobili. Strobili are stems with modified leaves– spppyorophylls—clustered on them. These are often called sporangiophores on Equisetum.

http://www.sbs.utexas.edu/bio406d/images/pics/ equ/Equisetum%20hyemale%20strob1.jpg

Equisetum: strobili

9 10/30/2011

Embryophytes

Pteridophytes “Bryophytes” To be cont. To Liverworts Hornworts Mosses Rhynia (Fossil) Rhynia Lycopodiophyta

megaphylls

Transition to land

Eusporangiate ferns: brief overview

--megaphylls --protosteles --homosporous --eusporangia --underground, non-photosynthetic gametophyte --includes Psilotales and Ophioglossales --7 genera, about 70 species

Eusporangiate ferns: Ophioglossales: Botrychium

What you’re seeing here is one leaf

http://www.rook.org/earl/bwca/nature/ferns/botrychium- multifidum-1sm.jpg

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Eusporangiate ferns: Ophioglossales: Ophioglossum

http://hengduan.huh.harvard.e du/fieldnotes/photos/show_ima ge?image_id=1140

Eusporangiate ferns: Psilotales:

http://t0.gstatic.com/images?q=tbn:ANd9GcRN0J vXD52gT892P9oJD7fNeMmehdMwcUyqLf8yF_A TVFbdvvh0

Embryophytes

Pteridophytes “Bryophytes” To be cont. To Liverworts Hornworts Mosses Rhynia (Fossil) Rhynia Lycopodiophyta

megaphylls

Transition to land

11 10/30/2011

Heterosporous ferns: brief overview --all aquatic --megaphylls --siphonosteles --heterosporous --leptosporangia --endosporic gametophyte --includes Marsileales and --5 genera, about 70 species

Heterosporous ferns: Salviniales:

http://nas.er.usgs.gov/XIMAGESERVERX/2007/20071004180006.jpg

Heterosporous ferns: Salviniales:

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Heterosporous ferns: Marsileales:

Embryophytes

Pteridophytes “Bryophytes” To be cont. To Liverworts Hornworts Mosses Rhynia (Fossil) Rhynia Lycopodiophyta

megaphylls

Transition to land

Filicales: brief overview

--megaphylls --siphonosteles (mostly) – few with eusteles --homosporous --leptosporangia --above-ground, photosynthetic gametophyte --about 320 genera, 10,500 species

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Filicales: Dennstaedtia

Filicales: Pteridium

http://t2.gstatic.com/images?q=tbn:ANd9GcQSnzinzDmcXng7WDPh3- KaypqI3JJUDSxUWSbyCjSa91eTqQOzcg

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