Mycorrhiza Types of Mycorrhiza Ecto-Mycorrhiza Endo-Mycorrhiza EctendoMycorrhiza Arbuscular mycorrhizas (AM) Ericoid mycorrhizas Arbutoid mycorrhizas Monotropoid mycorrhizas Orchidaceous mycorrhizas

1. Mycorrhiza and it’s types

2. Presented to:
Dr. Malka Saba
Presented by:
Muhammad Sohail Riaz
Dawood Abdullah
Syed Liaqat Shah
Muhammad Tahir Khan

3. Table of Contents
 Mycorrhiza
 Types of Mycorrhiza

4. Mycorrhiza
 Mycorrhizae literally translates to “fungus-root.”
 Mycorrhiza defines a (generally) mutually beneficial
relationship between the root of a plant and a fungus that
colonizes the plant root
 In many plants, mycorrhiza are fungi that grow inside the
plant’s roots, or on the surfaces of the roots

5. Cont…….
 In their relationship:
• Fungus facilitates water and nutrient uptake in the plant
• Fungus supplies the plant with water and mineral
nutrients, such as phosphorus (P), zinc (Zn), manganese
(Mn) and copper (Cu) taken from the soil
• Plant provides food and nutrients created by
photosynthesis to the fungus
• Plant makes organic molecules by photosynthesis and
supplies them to the fungus in the form of sugars or lipids

6. Cont…….
 Not all plants will have mycorrhizal
associations
 In environments in which water and
nutrients are abundant in the soil, plants do
not require the assistance of mycorrhizal
fungi, nor might mycorrhizal fungi
germinate and grow in such environments
 Mycorrhizas are present in about 92% of
the studied plant species, with arbuscular
being the predominant form in the plant
kingdom

7. Types of
Mycorrhiza
 On the basis of morphological and
anatomical features, Mycorrhiza
are divided into 3 types:
A. Ecto-Mycorrhiza
B. Endo-Mycorrhiza
C. EctendoMycorrhiza

8. A. Ectomycorrhiza (EcM)
 Ectomycorrhiza is a type of mycorrhiza that
forms a sheath around the roots of plants
 Ectomycorrhiza form a compact mantel of
hyphae on the outer surface of plant roots,
but do not penetrate plant root cells
 However, hyphal strands penetrate the root
surface and grow between cortical root
cells

9. Cont…….
 EcM associations occurs between the
roots of around 10% of plant families,
mostly woody plants
 Fungi belonging to
the Basidiomycota, Ascomycota,
and Zygomycota
 This type of mycorrhiza is found in trees
such as pines and oaks

10. B. Endomycorrhiza
 About 85 percent of the plant
families in the world are
colonized by endomycorrhiza
 Endomycorrhiza penetrates
the cell walls of the roots of
plants and colonize
epidermal and fleshy cortical
cells of plant roots
 This type of mycorrhiza is
found in plants such as
tomatoes, potatoes, carrots,
and legumes

12. C. Ectendomycorrhiza
 Ectomycorrhizas consist of a hyphal sheath, or mantle,
covering the root tip and a Harting net of hyphae
surrounding the plant cells within the root cortex
 In some cases the hyphae may also penetrate the plant
cells, in which case the mycorrhiza is called an
Ectendomycorrhiza
 Ectendomycorrhizas are restricted mostly to the plant
families Pinus (pine), Picea (spruce) and to a lesser
extent Larix (larch)

13. Cont…….
 The term ectendomycorrhiza should be used as a purely
descriptive name for mycorrhizal roots which exhibit the
characteristics of both:
• Ectomycorrhizas
• Endomycorrhizas

15. Types of
Endomycorrhiza

16. Cont…….
 Endo Mycorrhiza further classified into 5 types:
1. Arbuscular mycorrhizas (AM)
2. Ericoid mycorrhizas
3. Arbutoid mycorrhizas
4. Monotropoid mycorrhizas
5. Orchidaceous mycorrhizas

17. 1. Arbuscular Mycorrhizae
 Arbuscular mycorrhizae are branched structures that
penetrate the cell walls of plant roots
 This type of mycorrhiza is found in most plants, including
grasses, shrubs, and herbs
 The fungi involved in this relationship belong to the
phylum Glomeromycota
 It is estimated that around 80% of all plant species form
arbuscular mycorrhizal partnerships

18. Cont…….
 The mycorrhizal fungi colonize the roots of the host plant,
forming structures called arbuscules and vesicles within
the root cells
 Arbuscules are tree-like structures that facilitate nutrient
exchange between the fungus and the plant
 Vesicles are storage organs within the root cells that
contain lipids and carbohydrates

21. 2. Ericoid mycorrhiza
 Ericoid mycorrhiza is another type of
symbiotic association between plants and fungi
 Specifically involves plants from the Ericaceae
family
 It includes heathers, rhododendrons,
blueberries, and various other acid-loving
plants
 The fungi involved in ericoid mycorrhizal
associations are typically members of the
fungal group known as Ascomycota
(Hymenoscyphus ericae)

22. Cont…….
 Ericoid mycorrhizal associations are well-suited for plants
in acidic soils
 In ericoid mycorrhizal associations, the fungal hyphae
(thread-like structures) of the ascomycete fungi penetrate
the cell
 Fungal sheath, harting net and vesicles are absent

24. 3. Arbutoid mycorrhizas
 Found in the plant order Ericales
 Family Ericaceae is represented, with arbutoid
mycorrhizas
 Formed in the genera Arctostaphylos and Arbutus
 Arbutoid associations are also found in the Pyrolaceae
family of the Order Ericales
 Fungi of arbutoid mycorrhizas are basidiomycetes

25. Cont…….
 A fungal sheath or mantle of between 20 and 80 mm
covers the roots
 The sheath can also provide an important store of
nutrients, to be released to the plant when nutrient levels
are sufficiently depleted
 Arbutoid associations produce an intercellular harting net,
usually restricted to the outer layer of root cells

27. 4. Monotropoid mycorrhizas
 Fungi colonising achlorophylous plants in the
Monotropaceae family (but now included within the
Ericaceae), such as:
 Monotropa hypopitys (in Europe)
 M. uniflora (North America)
 These never actually penetrate the plant cell walls
 This feature was sufficiently distinct to warrant the
creation of a new class of mycorrhizas: the monotropoid
mycorrhizas

28. Cont…….
 Fungi belonging to Basidiomycota
 Fungal sheath and harting net is present along with
extensive intracellular penetration, with coils of hyphae
filling large volumes in many cells
 The root system of Monotropa is highly adapted to
gaining all its nutrients via mycorrhizas
 Its roots are surrounded in a dense fungal sheath, from
which hyphae spread into the soil

30. 5. Orchidaceous mycorrhizas
 The Orchidaceae is one of the largest families in the plant
kingdom, with more than 20,000 species identified, most
distributed in the tropics and subtropics
 All orchids have a stage where they are non-
photosynthetic
 Therefore dependent on external sources of nutrients
 In the vast majority of cases, it is just the seedling stage
that is obligately mycorrhizal

31. Cont…….
 Orchid seeds are very small (around 0.3 - 14 mg per seed)
and contain little nutrient reserves
 Mycorrhizal fungi can provide the nutrients, and
particularly carbohydrates, needed to grow, and in fact,
most orchid seeds will not germinate unless they have
been infected by an appropriate fungus
 The mycorrhizal fungi in orchids are Basidiomycota, and
in particular Rhizoctonia species with which many
orchids are associated