It's relationship between fungi and orchid. It's called symbiotic relation. The type of fungi is endomycorrhizae. fungi is help in take phosphorus and nitrogen in soil and orchid gave a nutrition in fungi.

1.  ORCHID MYCORRHIZAE
• Presented by :- Parekh Nidhi Jagdishbhai
• Roll No :- 12
• College :- M. N college, Visnagar

2.  CONTENT
 Mycorrhizae definition
 Types
 Orchid Mycorrhizae
 Role in seed germination
 seed germination
 Factors affecting seed germination
 Nutrients exchange between orchid and Mycorrhizal fungi

3.  MYCORRHIZAE
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 Mycorrhiza are a symbiotic association between plant roots and
fungi.
 There major role is to enhance nutrient and water uptake by the
host plant by exploiting a large volume of soil then roots alone
can do.
 The plant provides the fungus with carbohydrates formed from
photosynthesis.

4.  TYPES :-
1) Endomycorrhizae
2) Ectomycorrhizae

5.  ORCHID MYCORRHIZAE
 Micorrhiza in orchid species are highly important throughout their
whole life including germination and further development.
 The early stage of orchid reproduction and development, especially
the germination of orchid seed, are highly influenced by the
relationship with their appropriate mycorrhizal fungi as well as their
surrounding environments.

6.  FUNGI FORMING ORCHID MYCORRHIZAE
 The man group of fungi in habiting orchid roots is basidiomycetes, this fungi
come from range of taxa including
 Pathogenic Rhizoctonia.
 Sebacina,
 Tulasnella
 Russula species.
 Though rare in orchids, Ascomycete association have been documented in
serveral orchid species.

7.  ROLE IN SEED GERMINATION
 The most important contribution of mycorrhizal fungi to orchid is supplying nutrition for growth
and development.
 Orchid seeds under natural conditions are unable to germinate without a supply of C, mineral
nutrients as well as vitamins from their symbiotic partners.
 Additionally, Mycorrhizal fungi also contribute to supplying and retaining water for orchid
species during germination.
 This is also a highly essential roll of mycorrhizal fungi because orchid seeds commonly have a
hydrophobic testa to avoid imbibition in unfavourable environments.

8.  SEED GERMINATION
 Under the coexistence with mycorrhizal fungi, orchid seed can
germinate and develop into unique seedling structure called
protocorm that consist of parenchyma cells.
 Then for the development of the protocorm into plant is also
supported by their mycorrhizal fungi.
 In protocorm of orchid, the entered fungal hyphae from coiled
complex called Pelotons.
 Orchid can obtain nutrients by digesting them.

9.  FACTORS AFFECTING SEED GERMINATION
 Many environmental factor including abiotic factors, such as a
 light
 Soil structure
 Moisture
 And biotic factors, such as a microorganism
 Are required to be considered for the successful germination of orchid seeds and further
development
 This factor affect not only orchid seeds but also the success in symbiotic association
between orchid and micorrhizal fungi.
 FOR EXAMPLE :-
 It has been shown that organ development of symbiotic orchid seedlings and development
of photosynthetic structure are affected by light intensity, whereas development of micro
tropic tissues suppress the by light.

10.  NUTRIENT EXCHANGE
 Mycorrhizal symbiosis are important for the growth and survival of many plant species and a
responsible for up to 80% of nitrogen and phosphorus uptake by plants.
 In general, o mutualistic relationship for nutrient exchange is established between plant and
micorrhizal fungi in which plant provide photosynthetically fixed C to the symbiotic fungi and
the y benefit from fungi with regard to absorption of mineral nutrient such as N and P.
 Compared to the other types of mycorrhizas, the orchid fungus symbiosis is considered to be
unique since the nutrient movement is not bi-directional in the early development stages and
even in adults of some orchid species.
 As the orchid Seeds are Very tiny with very little storage, colonization buy fungi is required for
their germination and/or early protocorm development.

11.  Therefore, the mycorrhizal fungi Were throughout to
provide both mineral nutrient and carbon to the non
photosynthetic orchid seedlings and to receive no reward.
 However, similar to all other mycorrhizal symbioses, the
mycorrhizal fungi receive C as a reward for exchanging
mineral nutrient after orchid develop green leaves for
photosynthesis.
 Although the majority of orchid are autotrophic with
photosynthetic ability, more than 100 species are my
coheterotropic which are completely achlorophylls and
nutritionally dependent on their symbiotic fungi
throughout the whole life cycle.