 |
| ECTOMYCORRHYZA |
Mycorrhiza
means (Fungus root), is a mutualistic association of vascular plant root and
Fungi, and are central to the process of nutrient capture and recycling for
higher plants in low nutrients soil. They are important in the acquisition of
scare nutrients by the plant.
Network of
Fungi hyphae radiate outward into the soil from Mycorrhiza root, and with the
aid of an array of enzymes, soil bound nutrients are taken up.
The
network access soil nutrients far more than plant roots alone. The Fungi acts
as an extension of root system resulting in improved nutrient uptake for the
plant.
They are
of great importance in natural ecosystem and agriculture. Plants generally grow
poorly when deprived of their special root (Mycorrhiza). The Fungus either
forms a sheath around the root or penetrates the root tissues, thereby greatly
increasing the surface area of the root through outward extension of hypae.
TYPES OF MYCORRHIZA
There are
two types,
Ectomycorrhiza:- in this type, the fungus form a
sheath around the fine root of plants,
including major forest trees, the fungi does not penetrate between the
cells. Most fungi that form Mycorrhiza
produce large fruit bodies. SEE DIAGRAMS.
Endomycorrhiza:-
This does not form sheath but the hypae do penetrate the inside of the
hypae of plant root cells. There are fewer species of endomycorhiza and they do
not produce large fruit bodies.
FUNCTIONS OF
MYCORRHIZA
a- It hypae binds soil particles which
contributes to soil structure and the formation of lichens.
b-This network of root buffers plants
against environmental stress such as disease e.g, protecting plant against
pathogen by increasing host vigor and by acting as a barrier to root pathogens. It enhance proficient absorption of
mineral especially phosphate.
c- It secretes acids that increases the
solubility of minerals and convert them to forms that are readily used by
plant.
d- It absorbs water for the plant.
e- Mycorrhiza are common adaptation of
plants growing in poor soil.
0 Comments