2. Content
● Introduction
● Types of mycorrhiza
● Ecto mycorrhiza a) Monotropoid b) Arbutoid c) Orchid d) Ericoid
● Endomycorrhiza Or vascular arbascular mycorrhiza (VAM)
● Comparative diagram
● Benefits of arbuscular mycorrhizal association
● Research paper related to disease Control through mycorrhiza
● References
3. Introduction
● The term mycorrhiza, meaning fungi to the root.
● It was used for the first time in the year 1885 by A. B. Frank.
● Mycorrhizas are symbiotic associations essential for one or both partners,
between a fungus (specialized for life in soils and plants) and a root (or other
substrate-contacting organ) of a living plant, that is primarily responsible for
nutrient transfer.
4. Types of Mycorrhiza
1 Ectomycorrhiza
a) Monotropoid
b) Arbutoid
c) Orchid
d) Ericoid
2) Endomycorrhiza Or vascular arbascular mycorrhiza (VAM)
5. Ectomycorrhiza
Based on its penetration within the roots, Frank classified Mycorrhiza into two major class
Ectomycorrhiza :
● Ectomycorrhizas (ECM) are associations where fungi
form a mantle( sheath) around roots and a Hartig
net between root cells.
● These associations are defined by Hartig net hyphae
which grow around cells in the epidermis or cortex of
short swollen lateral roots.
● Fungal association : Higher fungi
(ascomycetes ,basidiomycetes and zygomycetes)
Cortical Hartig net of Pinus ECM
root.
6. Figure: Short roots coated with white hyphal net.
Digrammatic representation of EcM colonization in plant root
Source: http://upload.wikimedia.org/wikipedia/commons/9/9d/Ectomycorrhizae_001.jpg
Source: http://www.scivit.de/blog/wp-content/uploads/2010/08/quer.jpg
7. Figure: Colonization of Ectomycorrhiza in plant root
Source:http://upload.wikimedia.org/wikipedia/commons/6/69/Ectomycorrhiza_illustration.j
8. Monotropoid mycorrhiza
Monotropoid mycorrhizas are ECM associations of a few genera of myco-
heterotrophic plants in the Ericaceae.
These associations are characterised by limited hyphal penetration into epidermal
cells. Information on structure of associations and the identity of mycorrhizal fungi
in Monotropa, Pterospora, Sarcodes, etc. is provided by Robertson & Robertson
(1982), Castellano & Trappe (1985) and Bidartondo et al. (2000).
Fungi - BASIDIOMYCETES
9. Figure : Monotropa root with epidermal Hartig net (H) and
mantle (M) in a cross-section viewed with UV light. Roll-over -
hypha projecting into an epidermal cell (arrow) in stained root
section.
Monotropa uniflora is a myco-
heterotrophic plant lacking chlorophyll
that is entirely dependant on ECM fungi
linked to nearby trees.
10. Orchid Mycorrhizas
Orchid mycorrhizas consist of coils of hyphae within roots or stems of
orchidaceous plants.
Hyphal coils from orchid mycorrhizas
in Epipactis helleborine root.
Coils are white to brown fuzzy balls. This rhizome
of the Western Underground Orchid (Rhizanthella
gardneri)
11. Ericoid mycorrhiza
Ericoid mycorrhizas have hyphal coils in outer cells of the narrow "hair roots" of
plants in the family Ericaceae
Fungi associated -
Mostly ascomycetes
Fig : Ericoid mycorrhizas with hyphal coils in hair roots of
Leucopogon verticillatus.
( Source: http://mycorrhizas.info/ )
12. Endomycorrhiza or Vesicular-Arbuscular
Mycorrhiza (VAM)
Arbuscular mycorrhizas (Vesicular-Arbuscular Mycorrhizas, VAM or AM) are
associations where Glomeromycete fungi produce arbuscules, hyphae, and
vesicles within root cortex cells.
These associations are defined by the presence of arbuscules.
Fungi in roots spread by linear hyphae or coiled hyphae.
13. Figure: Arbuscular mycorrhizal fungi in the roots of weeds (A) Arbuscule (ar ) in Amaranthus retroflexus; (B)
Vesicle (vs) and hyphae (hy) in Sinapsis arvense; (C) Leonurus sibiricus; (D) Leonitis neptaefolia; (E) Spore
(sp) in Paniculum maximum; (F) Hyphal coils (hc) in Sorghum arundaceum.
Source:http://www.scielo.br/scielo.php?pid=S1807-86212013000100006&script=sci_arttext (CC)
14. Arbescules and vesicles
AM hyphae do not in fact penetrate the protoplast, but invaginate the cell
membrane.
They have two types of mycelium systems: external and internal
External mycelium grows and spreads inside the soil, and is able to ease into the
tiny pores of the soil where plant roots are normally out of reach.
Internal mycelium grows in between and inside the parenchymatous cells of the
host plant roots and create many branches known as arbuscules within the plant
root cells.
15.
16. Benefits of Arbuscular Mycorrhizal Association
1. Absorption of nutrients
2. Protection against pathogen
3. Protection against abiotic stres like ;
I. Salinity stress - by enhancing selective uptake of nutrients
II. Drought stress- ability to alter plant water status
III. Heavy Metal- selects between essential and non essential metals
17.
18. References :
Himaya SMMS1*, Sivasubramaniam N2, and Afreen SMMS3
A Review on Role of Mycorrhizal Fungi in Plant Disease Management
http://seu.ac.lk/sljot/publication/v1n2/sljot2
Smith S.E. and. D.J. Read. 1997. Mycorrhizal Symbiosis (second Ed.). Academic
Press, San Diego and London.
http://link.springer.com/article/10.1007%2Fs00572-013-0486-y/fulltext.html
http://mycorrhizalsymbiotics.com/plantlist
