Charophyta PPT BY Dr.Pinky Diwedi

1. Charophyta
M.Sc.Isem, unit-II
Dr.Pinky Dwivedi
.

2. • Commonly called as stoneworts.
• Occurs in still, clean, fresh or brackish water.
• Sub-aquatic,growing in shallow waters in soft
mud, from Aug. to March.
• Both living and fossil form.
• living has 7 genera with 294 spp.
• In India -69 spp. Belonging to 5 genera.

3. Elaborate vegetative plant body,usually errect,
consist of long , slender, jointed green or grey
main axis .
Main axis branched with regular nodes and
internodes (equisetoid).
Internode- single elongated cell.
Node bears whorl of laterals of limited growth.
Grows by single dome shaped apical cell.
At the lower portion multicellular rhizoids are
present.

4. Vegetative reproduction – amylum stars, bulbils
and secondary protonema.
Asexual reproduction completely absent.
Sexual reproduction is oogamous, sex organs
are complex in structure and development,
sex organs are jacketed.
Male sex organ is called globule, antheridium
has wall made of shield cells- 4 in Nitella, 8 in
Chara .
Inner cavity has 4 manubria which on its inner
end bears capitulla cells which bears
spermatogenous filaments.

5. Female reproductive structure – oogonium, it is
oval, lies above the antheridium- nucule.
It is surrounded by protective sheath of five spirally
coiled cells which end into 5 corona cells in Chara
and 10 in Nitella.
Inside it is a single large egg or oogonium.
After fertilisation egg is retained in the oogonium.
Zygote germinates after resting period.
Before germination zygotic nucleus divides
meiotically, 3 haploid nuclei degenerate and
remaining one forms protonema from which
lateral bud arises which develops into new Chara
plant.

6. Affinities of Charophyta:
Characters of group-
Equisetoid thallus with rhizoids, ariel branched
structure, with nodes and internodes.
nodal arrangement of branches in whorls.
apical growth.
Sex organs complex, jacketed.
Antherozoids spirally coiled , biflagellated.
Development of new plant from lateral bud of
protonema.
These characters are advanced characters,which
are distinct from algae.

7. They also show:
Absence of alternation of generation.
Male and female sex organs though
jacketed but are simple.
Zygote undergoes zygotic meiosis.