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Mycorrhiza
By Nitika Kapoor-1939115

Introduction
1)

2)

3)

A mycorrhiza is a symbiotic, generally mutualistic association between a fungus and the
roots of a vascular plant in which each benefits from the other: the plant supplies the
fungus with photosynthetic products such as sugars,and the fungus supplies the plant with
minerals and water
...

In most of the cases plant seedling fails to grow if the soil does not contain inoculum of
mycorrhizal fungi
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They also increase the resistance in plants against plant pathogens and surface
area of the root system for better absorption of nutrients from soil
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Types of Mycorrhiza
Marks (1991) divided mycorrhiza into categories on the basis of their relationship with the host
plant
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Ectomycorrhiza
Ectomycorrhizas, characterized by an intercellular network of hyphae—Hartig net—surrounding
but not penetrating the cortex cells of plant roots
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An important visible feature-Y-shaped rootlets
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g
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Hartig netLabyrinthine network of specialised fungus hyphae, with frequent branching (or wall ingrowths)
that forms a layer between the walls of adjacent root epidermal or cortex cells
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Ectomycorrhiza showing Hartigs net
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Most endomycorrhizae contain
both vesicles and arbuscules and are, therefore, called vesicular–arbuscular mycorrhizae
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Endomycorrhizae are also produced by some basidiomycetes
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It should be mentioned that in some instances
more than one of the above mycorrhizal types
may be observed along the root system of a
single plant; Navarro-Ro ́denas et al
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”

Vesicular-Arbuscular Mycorrhiza
It is the most widespread and is present in all groups of plant kingdom- 70-90%
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Fungi classification- Phylum- Glomeromycota
Division- Ascomycetes, Basidiomycetes, Zygomycetes
7 Genera- Acaulospora, Gigaspora, Glomus, Sclerocystis, Scutellospora, Entrophospora,
Gerdemannia
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Forms two bodiesArbuscules- • transfer mineral nutrients from fungi • transfer sugars from host to fungi
Vesicles- storage organ of P as phospholipid
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Mycorrhizal plants can absorb and accumulate several times more phosphate from the soil or solution
than non–mycorrhizal plants
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They belong to Basidiomycetes and colonise the Arbutus genera
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Monotropoid Mycorrhiza
The fungi belong to Basidiomycetes and colonise the achlorophyllous members of Monotropaceae
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They have a fungal sheath and Hartig’s net with limited
hyphal penetration into epidermal cells
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Monotropa uniflora
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Mature plants
B
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C
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D
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Orchid Mycorrhiza
This type of fungus is imperative for the survival of the
orchid seedling as it is achlorophyllous
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Both the plant and fungus are living, but the
fungus degrades over a period of time
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Orchid mycorrhiza
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Here, the roots of the plant have been invaded with the filamentous
hyphae (green) the fungus, through the epidermis and outer cortex
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Benefits of using Mycorrhiza as a Biofertilizer
(i) They increase the longevity of feeder roots, surface area of roots by forming mantle and spreading
mycelium into soil and, in turn, the rate of absorption of major and minor nutrients from soil resulting in
enhanced plant growth
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These are available to plants in less amount (Tinker, 1984)
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(iv) VA mycorrhizal fungi reduce plant response to soil stress
such as high salt levels, toxicity associated with heavy metals,
mine spoils, drought and minor element (e
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Mn) imbalance
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Thus, they play a significant role in augmenting soil fertility and plant nutrition
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(vii) Their presence reduce the effects of pathogens and pests on plant health
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Mycorrhiza are endurable to several
chemical substances; for example; pesticide such as endrin, chlordane, methyl parathion,
methomyl carbofuran; herbicide such as glyphosate, fluazifop-butyl; chemical agents for plant
disease elimination such as benomyl, maneb triforine, mancozeb and zineb
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researchgate
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&text=They%20also%20increase%20the%20resistance,biofertilizer%20and%20as%20bioc
ontrol%20agent
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info/ecm
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com/index/biotechnology/plant_biotechnology/biofertilizers/biotech_mycorrhizae_biofertilizer
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ncbi
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nih
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frontiersin
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3389/fmicb
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01559/full
https://www
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net/publication/281662366_Role_of_mycorrhizae_as_biofertilizer_and_bioprotectant#:~:text=Mycorrhizae%20are%20obligat
e%20fungi%20that,and%20soil%20of%20higher%20plants
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https://www
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mext
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jp/english/bf/bfm/pdf/4_3_Mycorrhiza0403
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sciencephoto
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researchgate

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