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close this bookBiodiversity in the Western Ghats: An Information Kit (IIRR, 1994, 224 p.)
close this folder6. Plants, fungi and bacteria
View the document6.1 Plant associations of the central Western Ghats
View the document6.2 Rare and endangered flowering plants
View the document6.3 Medicinal resources from the forest and sea
View the document6.4 Poisonous plants
View the document6.5 Fungi: Biodiversity, ecology and use
View the document6.6 Conserving fungi
View the document6.7 Edible mushrooms
View the document6.8 Microbial biodiversity of salt pans

6.7 Edible mushrooms

Mushrooms are beneficial higher fungi. They have been used as food ever since the hunting-and-gathering stage of our prehistoric forebears.

A majority (80-90 %) of the edible mushrooms belong to the taxonomic order Agaricales.

India's mushroom biodiversity

Mushrooms in India are very diverse but not well known. India has from 1105 to 1208 species of mushrooms belonging to 128130 genera. Of these, only 300-315 species belonging to 75-80 genera are considered edible.

The Western Ghats have a wealth of mushroom flora: 700-750 species belonging to 70-75 genera. Of these, only 70-80 species are known by local communities in Maharashtra, Karnataka, Goa, Kerala and Tamil Nadu to be safe for human consumption.

Among all the popular edible mushrooms, the species of the termitophilic genera Termitomyces, Podabrella, the wood decomposer Pleurotus, and the ectomycorrhizhal Boletaceae are dominant.

Wild edible mushrooms have interesting local names. These are derived from either the habitat (e.g., Roen olmi = termite hill mushroom), shape (Khut olme = mushroom with crutch, Fugo = balloon), colour (Tamdi olmi), size or occasionally the fruiting season (Shit) olmi, which fruit during winter).

Fungi as friends and foes of humans

As friends

As foes

Biotransformations

Plant diseases

Antibiotics

Animal and human mycoses

Plant growth hormones


Industrial enzymes

Mycotoxins

Mycoproteins

Spoilage

Biological control

Allergens

Mycorrhizal associations


Mushroom diversity in Western Ghats states

State

Genera

Species

Edible spp.

Gujarat

5

5

0

Maharashtra

45

171

50

Goa

36*

87*

87

Karnataka

30

43

15

Kerala

41

88

75

Tamil Nadu

63

220

35

* Edible species only

World mushroom biodiversity
Order Agaricules


World

India

Genera

230

128+

Species

6000+

1200

Edible sp.

2000

300+


Edible mushrooms

Termite hill mushrooms

As their name suggests, termite hill (or "termitophilic") mushrooms grow on termite hills. Termites cultivate these mushrooms and eat them to obtain enzymes and nitrogen. People harvest the mushrooms which emerge from the underground fungal combs and market them in large quantities.

The entire life cycle of these popular mushrooms is considered ecological magic by local termite-hill goddess worshippers. The mushrooms have given rise to many interesting taboos and folk-beliefs. For instance, the termite hills are closely guarded and revered as the abode of a popular local goddess. These beliefs once checked the exploitation of mushrooms and destruction of the termite hills, but a sudden spurt in consumer demand for wild termite hill mushrooms (especially in Goa) is threatening this conservation ethic.

Almost half the above-ground plant litter in the Western Ghats forest and bamboo groves is recycled by Termitomyces. This is a vital way the soil nutrient reservoir is enriched.

Termites and the gods

The termite hill goddess is venerated in Konkan, Goa and Kanara and is known as "Santeri", "Bhumikon, "Shantala" or "Shantadurga". Every temple has a holy termite in the sanctum sanctorum.


Termite hills

Termitophilic mushrooms of the Western Ghats

The Western Ghats have world's largest gene pool of Termitomyces. This diversity is threatened by overexploitation and subsequent extinction.

Genera

World (spp.)

W Ghats (spp.)

Podabrella

6

4

Termitomyces

41

25

Sinotermitomyces

3

-

Termite hills

Each hectare of forest in the Western Ghats has about 810 termite hills. In mixed forests, termites invade between 21 and 79% of trees. Termites turn over large amounts of soil by plastering on trees and the ground.

The plant material taken inside the termite hill ends up in the "fungal comb". Each comb weighs 28-31 kg.

The Termitomyces fungus in the comb decomposes 167 to 341 kg of organic matter a year.

Fungi and their "masters"

The biodiversity of Termitomyces fungi parallels their "masters" or partners-the termite species that cultivate them for food.

Dominant termite species*

Dominant fungus species

Odototermes horni

Termitomyces striatus

O. obesus

T. heimIi

O. feae

T. currhizus

O. wallonensis

T. mammifornis

O. redemand

T. clypeatus

O. malabaricus

T. microcarpus

O. brunneus

Podabrella microcarpa

Macrotermes sp.


Microtermes sp.


* all of Macrotermitinae subfamily of higher termites


Termites

Significance of biodiversity

· The Western Ghats mushroom flora closely resemble flora of Africa and South America. This affinity is related to geodynamical events like plate tectonics.

· Saprophytic or decomposer mushroom genera such Lepiota and Macrolepiota marasmius, opportunistic parasites such as Pleurotus and Lentinus termite, cultivated fungi such as Termitomyces, and ectomycorrhizal partners such as Russula help maintain the ecosystem by catalyzing the mineralization of organic matter.

· Carnivorous mushrooms species control nematode populations.

· Edible mushrooms provide a seasonal source of food to tribals. Wild mushrooms and their habitats such as termite hills have become fountainheads of folk belief systems and interlinked cults.

Threats to mushroom biodiversity

· Lack of comprehensive surveys.

· Habitat destruction (e.g., deforestation).

· Mega-projects (e.g., dams, highways, railway tracks).

· Shifting focus of urbanization and industrialization towards the hills from overcrowded coastal areas.

· Monoculture plantation such as eucalyptus, rubber and oilpalm.

· Kumeri, or "slash-and-burn" cultivation.

· Land use change and land development.

· Pollution.

· Artificial vegetation breaks.

· Increasing demand for wild edible species.

· Lack of public awareness and indifference of local authorities.


Common hymenophoral habit type in Agaricales

1 Amanitoid
2 Agancoid
3 Pholiotoid
4 Tricholomatoid
5 Clitocyboid
6 Collyboid
7 Mycenoid
8 Marasmioid

Edible mushrooms are balanced protein foods

Species

Water
%

Protein%

Fat
%

Button mushroom
(Agraicus sp.)

89

4.0

0.2

Dingri/oyster mushroom
(Pleurotus spp.)

90 *

3.0

0.7

Termite hill mushroom Termitomyces sp.)

91

4.0

0.2

Paddy straw mushroom
(Volvanella spp.)

88

4.5

0.5

% on fresh weight basis.
These species also contain thiamine, riboflavine, niacin, calcium, iron and phosphorus.

Ghost lights

Mycelium and fruiting bodies of bioluminescent mushroom species such as Lampteromyces, found in Western Ghat forests, emit a faint blue-green or violet light, occasionally illuminating entire forest at night. This "ghost glow" helps in spore dispersal.

Suggested conservation measures

· Extensive survey, documentation identification and cataloguing of mushroom species.

· Market surveys to establish exploitation consumption/trends

· Field studies to identify "hot spots".

· Notification of endangered species and habitats.

· Demarcation of "micro-bioreserves" of fungi/mushrooms.

· Detailed plan for controlled exploitation of non-endangered species on basis of phenological studies.

· Ex-situ conservation in the form of dried herbarium, spore-deposits and mycelial (tissue) cultures.

· Domestication of wild edible species e.g., Termitomyces for commercial cultivation.

· Establishment of valuable mushroom germplasm banks.

· Development of wild species mycelial culture to manufacture bioactive molecules, enzymes, polysoccharides, protein pellets, flavour and natural mycodyes, e.g., melanin.

· Culture of ectomycorhizal species as bioinoculants for use in agroforestry.

· Public awareness campaign through the mass media.

· Aesthetic use of mushroom biodiversity for nature promotion, e.g., in philately, models, cards and games.

· Removal of techno-legal ambiguities in existing eco-conservation and forest protection laws to incorporate concerns regarding fungal and mushroom biodiversity.

· Involvement of local communities and NGOs in a biodiversity awareness drive.

Ban on collection

A ban on wild mushroom collection in sanctuary areas of Goa was imposed after considerable lobbying. Despite political pressures, the forest department of Goa stood its ground and has enforced the ban since June 1992. Goa is the first state in Western Ghats to impose and enforce such a ban, aimed primarily to conserve the rich, diverse and precious edible Termitomyces gene pool.

Natural, biodegradable hair dye from fungus

Antromycopsis, a non-fruiting mushroom, produces drops of sticky viscous, black fluid on tips of its erect. mycelial bundles. This was found to be made of melanin. Non-toxic and insoluble in water, it could be manufactured in large quantities for use as hair dye.

Popular Goan mushroom dishes

Hot and spicy mushroom bhaji
Fried mushrooms
Mushroom kebabs
Omelettes, pizzas, mushroom sauce, pickles
Mushroom biryani and pulaos

Wild edible mushrooms are cooked in many ways in Goal. The nutritional value of mushrooms as sugar-free, protein-rich food supplement is well known. Although the demand for edible mush
rooms is rising due to the growth of tourism, only a few species are cultivated on a minor scale. Pressure on the wild population of edible mushrooms remains unabated.

Prepared by Dr. N. Kamat