Economical importance of bryophytes

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ECOLOGICAL IMPORTANCE OF BRYOPHYTES Mosses and Bryophytes are the first organiasms to colonise rocks. They colonise rock by acidic secretion. This acidic secretion is due to the death of mosses. When the rock is decomposed it helps in soil formation. Therefore New soils are formed. The soil act as binders.  It prevent soil erosion. The water retention capacity of the soil is high ie, water holding capacity of the soil is high.  This reduces surface water run-off which prevent soil erosion. Bryophyte helps in the recycling of nutrients. ECONOMICAL IMPORTANCE OF BRYOPHYTES. 1) SPHAGNUM Sphagnum has high absorptive power with antiseptic property. This can be used to replace cotton in bandages. 2) MERCHANTIA   Mercahntia cures pulmonary tuberculosisand affliction (pain) in liver. Antibiotic substances are also extracted from bryophytes. it also acts as antiseptic, and as preservative POLYTRICHUM Polytrichum dissolove stone in kidney and in gall bladder. 3) IN RESEARCH It is used in the fie
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archegoiate

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Hepatocospida 

it names fall apart as it looks like hepatic cell 
Hepatic cells are present in liver.
example :- liverworts
Example of liverworts are riccia and merchantia.


                                 Riccia



                         Merchantia

Hepatocospida is further divided into four orders

1) merchantiales
Ex- riccia and merchantia

2) sphaerocarpales 
Ex- sphaerocarpus

3) calobryales
Ex- calobryum

4) jungermanniales
Ex- pellia


Merchantiales



Terrestrial growing plants.
But grows on shady places, damp soil, moist area and bank of stream.

Internal structure of thallus

a)Ventral side.

- Thallus look like boat shaped.
- They are same gametophytic plant.
 ie, No difference of sex organ (male/female)

Upper epidermal, lower epidermal are present and in between them chloroplast containing cells are found.

~ Air chamber is present, also called air spore. 
~ This helps in exchange of gases. (Co2 and O2)
~ Scales are present.

Dorsal side.

Gemma cups are present.


                           Gemma cups

~ gemna cups indicates towards the asexual mode of reproduction.

Antheridiospores bear antheridia



~ Wheares archeagoniophores bear archegonia.




Rhizoids can be divided into two types

 1)smooth rhizoid
 2) tuberculate rhizoid


                             Rhizoids

~smooth is responsible for conduction of water 
~it have no walls hence more space is available for conduction of water.

  On the other hand,
- tuberculate penetrate and attach to the substrate
- it attaches strongly 
-tuberculate have wall 
-this wall penetrate down to substratum and make stronger attachment with substratum
- there is less space due for presence of wall, conduction process don't occur much.
- hence it is mainly  responsible for attachment to the substrate.




Morphology

-riccia fluitans
-riccia natans/rictocarpus natans
-They are found in aquatic habitat 
in India it is found in Dal lake of Kashmir ~ ~ till now 138 species found
- rhoeo discolour is the common species found in India.

Riccia is

-Green in colour
-More closed to and attached to substratum.
-Grow prostrate in size
i.e horizontal to the ground.
-Rosette in shape (rose shape)
-Spores are present, dorsal and ventral grooves are present.
-Thallus lobe contain apical notch.


Pellia epiphylla


Kingdom - plantae
Division - marchantiophyta
Class - jungermanniales
Family - pelliaceae
Genus - pellia
Species - p.epiphylla


Reproduction




 It carries out it's vegetative reproduction by three process 

a) by progressive growth of thallus and subsequent death and decay of older region 

b) multicellular gemmae formed from upper/superficial cells of thallus

c)by formation of underground tubers.



~ Antheridia develops from the upper dorsal cells close to the apical cell.
~ it is slightly embedded in the tissue of gametophytes



~ when they become mature they brust suddenly thereby releasing the antherozoids.


- A mature archegonium has a venter and a neck
-  venter contains a solitary ventral canal and an egg.

~ Fertilisation takes place in the presence of water. 
~ antherozoids swims into the venter  and fertilizes with an egg.
~ the fertilized egg surrounds itself by a wall and forms the oospores.
~ fertilization leads to oospore formation
then starts the sporophytic/diploid generation.

Sporophytic/diploid of pellia.




~ Archegonial venter is enlarged due to filling of oospores.(zygote)
~ During this calyptra is formed
~ Calyptra protects the capsule containing the embryonic sporophyte 
~ it vanishes before the sports are released from the capsule.

~ A single oospore develop.
Rest archegonia became abortive/failed to develop.

Oospore form :-

a) hypobasal cell~~~> no further division
b) epibasal cell 
(further division occurs and form octant)
From octant:- a) 4 upper cells
                        b) 4 lower cells

4 upper cells make capsule.
Capsule are of 2 types

a) Outer layer of cell
 -It is two layered cell.
 -The spore mother cell by meiotic division form the spore tetrads.

b) inner multi layered mass (endothecium)
It develops into sporogenous tissue and sterile elaters.

- Which reduction division and formation of spores the gametophytic/haploid generation begins
- sporangium of pellia requires a year for complete development 
- capsule is enclosed/surrounded by jacket inside capsule spores form a small,few - cells called ellipsoidal structure containing chloroplast.
- These spores are liberated at dehiscence of capsule
Therefore, these spores falls on suitable substaratum.



Thereby, germinating and giving rise to new gametophyte.




All the best😀



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