K. Surendirakumar

Introduction to

MYCORRHIZA

What is Mycorrhiza?

Albert Bernhard Frank (1885) – Germam botanist- Mycorrhiza from Greek “mukes +rhiza” means “fungus+ root”.

Mycorrhiza- Most important type of symbiotic plant-fungus association (Lewis-1985)

•movement of nutrients - carbon flows to the fungus and inorganic nutrients move to the plant

•mycorrhizas normally occur in roots, primary role of mycorrhizas is the transfer of mineral nutrients from fungus to plant.

Cont…• Mycorrhizas require synchronized plant-fungus

development, since hyphae only colonized young roots

Present in 90% of plants (83% Dicots, 79% Monocots and 100% Gymnosperms).

Brassicaceae, Cyperaceae, and Juncaceae- do not have mycorrhizal associations (10-20%).

Benefits of MycorrhizaeProduce more vigorous and healthy plantsIncrease plant establishment and survival at seedling or

transplanting,Enhance flowering and fruiting,Increase yields and crop quality, Improve drought tolerance, allowing watering reduction,Optimize fertilizers use, especially phosphorus,increase tolerance to soil salinity, Reduce disease occurrence,Contribute to maintain soil quality and nutrient cycling,

contribute to control soil erosion.

Mycorrhizae

Ectomuc

Classification of MycorrhizaBased on tropic level by A.B. FrankEctotropic MycorrhizaEndotropic Mycorrhiza

Based on morphological and anatomical featureEctomycorrhizaEndomycorrhizaEctendomycorrhiza

Broadly classify into seven categories

•Endomycorrhiza (AM / VAM)

•Ectomycorrhiza (ECM)

•Monotropoid Mycorrhiza

•Arbutoid Mycorrhiza

•Orchid Mycorrhiza

•Ericoid Mycorrhiza

•Ectendo- mycorrhiza

Type of mycorrhizaeNo. Mycorrhiza Fungi -Phylum Definition Host

1 Endomycorrhiza (AM) 

Glomeromycota Glomeromycotan fungi- Arbuscules, vesicles Plants (All types)

2 Ectomycorrhiza (ECM) Higher fungi (asco,basidio and zycomycetes)

Hyphal mantle, Harting net Plants (Trees) Pinaceae, Fagaceae, Myrtaceae and Betulaceae

3 Monotropoid Mycorrhiza

Basidiomycetes Exploitative epidermal ECM-myco-heterotropic plants-Ericaceae-individual hyphae penetrate epidermal cells

achlorophyllous plants -Monotropaceae, Ericaceae (Monotropa, Pterospora)

4 Arbutoid Mycorrhiza Basidiomycetes ECM of autotropic plants-Ericaceae-multiple hyphae Arbutus, Arctostaphylos and several species of the Pyrolaceae, Ericaceae

5 Orchid Mycorrhiza Most are Basidiomycetes Coils of hyphae (pelotons)penetrate within cells Orchidaceae

6 Ericoid Mycorrhiza Most are Ascomycetes Coils of hyphae within very thin roots -Ericaceae Callanu and Rhododendron Ericaceae (most genera)

7 Ectendo- mycorrhiza Ascomycetes Several fungi colonize single plant-lacking hyphae in harting net

Eucalyuptus, Alnus, Salix etc…

Arbutoid mycorrhiza

Ericoid mycorrhiza

Orchid mycorrhiza

Endomycorrhiza and Ectomycorrhiza

Monotropoid mycorrhiza

Pelotons