Experimental Design and Observations

1. INTRODUCTION

Mycenean, which primarily concerns with the development of Mycology

(Gr. Mykes = mushroom + logos = discourse) as a discipline, is one of the greatest

civilizations that man has developed. It seems to have been named after a legendary

mushroom (Alexopoulos et al., 1996), a term which is thought to have been derived

from a French word “mousseron”. Mushrooms are fleshy mysterious life forms

which have attracted the attention of naturalists before the invention of microscope.

Their nature and origin have puzzled the man primarily because of their diverse

morphological and qualitative characters. References of mushrooms can be seen in

almost every civilization records, whether they are Romans, Greeks or Chinese.

Some used them as food while others considered them as medicine or for spiritual

purposes (Rai and Arumuganathan, 2003). Technically these are epigeous /

hypogeous fruiting bodies of higher fungi belonging to Ascomycota and

Basidiomycota (Purkayastha and Chandra, 1985). They grow naturally above

ground or on the soil, on tree trunks, leaves and roots of trees as well as on decaying

woody materials, organic wastes, dung, agricultural wastes or even underground and

many of them formed unique symbiotic associations with the roots of variety of

plants (Singer, 1986). They are both edible and non edible. Apart from being taken

as food, they are an important source of nutraceutical products with multifarious

health benefits.

People, in modern times, are becoming more health conscious. Mushrooms

fit themselves well, to meet the dietary requirements as best low calorie food along

with their delicious taste and flavor, in the present day menu. Because of their

growing relevance in our day to day life, lot of emphasis is being laid on their

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Experimental Design and Observations

identification, characterization, domestication and technological improvement for

their bulk production (Purkayastha and Chandra, 1985). Currently 14,000 mushroom

species are known to exist. Out of these about 50 % or 7000 species are considered

to possess varying degrees of edibility and almost 3000 species spread over 31

genera are regarded as prime edible mushrooms. To date only 200 of them are

experimentally grown, 100 of them economically cultivated, approximately 60

commercially cultivated and about 10 have reached to industrial scale production in

many countries (Tewari, 2005). Furthermore, about 2000 are medicinal mushrooms

with varieties of health attributes. The poisonous mushrooms are relatively small in

number (approximately 1 %) but there is an estimate that about 10 % may have

poisonous attributes while 30 species are considered to be lethal (Tewari, 2005).

The Chinese were the first to start artificial cultivation of mushrooms.

Particularly, Auricularia polytricha (Mont.) Sacc. in 600 AD, Flammulina velutipes

(Curtis) Singer in 800 AD and Lentinula edodes (Berk.) Pegler in 1000 AD. But real

commercial ventures began with Europeans when they started cultivation of button

mushroom in caves during 16th & 17th centuries. Today mushroom farming is being

practised in more than 100 countries (Tewari, 2005). Major exporting countries of

fresh mushrooms are Netherlands, Poland, Ireland and Belgium. Mushroom

production in India has been estimated at 48,000 tonnes (Harsh and Joshi, 2008).

The commonly cultivated mushrooms are Agaricus bisporus (J. E. Lange) Imbach

(Button mushroom), Lentinula edodes (Berk.) Pegler (Shiitake), Volvariella spp.

(Paddy straw mushroom), Pleurotus spp. (Oyster mushroom), Auricularia

polytricha (Mont.) Sacc. (Black ear mushroom), etc.

The Chinese were the first to start the cultivation of genus Lentinus Fr. in

1000 to 1100 AD (Chang and Miles, 1987). As a consequence of the work done on

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Experimental Design and Observations

these lines since then, technology for some of the mushrooms like A. bisporus (J. E.

Lange) Imbach, Lentinula edodes (Berk.) Pegler, Volvariella volvacea (Bulliard ex

Fries) Singer, Pleurotus spp., Flammulina velutipes (Curtis) Singer has been

perfected resulting in world’s total mushroom production touching 5 million tonnes

with annual growth rate of 7 percent and it may touch 7 million tonnes by 2010

(Singh and Singh, 2006). The worldwide production of mushrooms over the last two

decades has shown a phenomenal pattern of growth with five times increase in

tonnage while in case of Agaricus bisporus (J. E. Lange) Imbach world production

dropped from 77 % to 31.9 % by 1997 (Chang, 2006).

Lentinula edodes (Berk.) Pegler is the second important species after

Agaricus bisporus (J. E. Lange) Imbach which is widely consumed and is highly

prized for its flavor and health benefits. From India point of view it is a specialty

mushroom. Because of its food and medicinal properties, it has always attracted the

scientists and as a consequence of which work is being done on this mushroom

(Sharma, 1997). Besides, there are number of other mushrooms falling in the

category of specialty mushrooms which are gaining importance because of their

acceptable culinary and nutraceutical attributes. Some of these are Pleurotus spp.

(Dhingri), Volvariella spp. (Paddy straw mushroom), Auricularia polytricha (Mont.)

Sacc. (Black ear), Calocybe indica P. & C.(Milky mushroom), Stropharia rugoso-

annulata Farlow & Murrill (Giant mushroom), Flammulina velutipes (Curtis) Singer

(Winter mushroom), Pholiota nameko (T.Ito) S.Ito & Imai (Nameko), Coprinus

lagopus Fr . (Ink cap), Tremella fuciformis Berkeley (Silver ear), Dictyophora

duplicata (Bamboo sprouts), Ganoderma lucidum (Curtis) P. Karst. (Reishi), etc.

(Sharma, 1997; Tewari, 2003). On the same line highly prized Nigerian edible

mushroom Lentinus squarrosulus (Mont.) Singer can also be clubbed amongst the

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Experimental Design and Observations

category of specialty mushrooms from India point of view as there is hardly any

attempt to popularize this mushroom in India, although it is quite common in the

Northern and Southern part of India.

Genus Lentinus belongs to family Polyporaceae and is recognized by as

many as 40 species the worldover (Kirk et al., 2008). Some of the important species

are L. lepideus (Buxb.) Fr., L. kauffmanii A. H. Smith, L. cladopus Lév., L.

glabratus Mont., L. polychorus Lév., L. tuberregium (Fr.) Fr. and L. cochleatus

(Pers. ex Fr.) Fr. Out of these L. lepideus (Buxb.) Fr. and L. kauffmanii A. H. Smith

are destructive parasite of wood while L. tigrinus (Bull.) Fr. is a common wood

decaying fungus.

Lentinus squarrosulus (Mont.) Singer, on which the present investigation has

been undertaken, is a highly prized Nigerian edible mushroom of class -

Agaricomycetes, order - Polyporales and family - Polyporaceae (Kirk et al., 2008;

Abbot et al., 2008). This is a common, widespread, palaeotropical species, most

closely related to L. sajor-caju (Fr.) Fr. with a similar dimitic hyphal system

containing bovista type binding hyphae (Pegler, 1977). The basidiocarp of the

fungus is fleshy and creamish white and it grows on dead wood and grasses

naturally and almost on all agricultural wastes. From nutritional point of view, it is

reported to contain higher dry matter, protein and fiber content and lower fat

content. In India, preliminary culture and nutritive studies of L. squarrosulus

(Mont.) Singer were undertaken on a sample collected from Bhutan by Upadhyay

and Rai (1999) at Directorate of Mushroom Research, Solan. Some culture work on

this species has also been done by Natarajan and Manjula (1978) at Madras.

Not much work on this species has been done the worldover, except for some

in African countries like Nigeria, Congo and South-East Asian nations like

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Experimental Design and Observations

Thailand, Malawi, etc. (Jose and Kayode, 2009). Keeping in view the nutritional and

nutraceutical importance of L. squarrosulus (Mont.) Singer and the paucity of work

for its domestication and successful production in India, the present investigation on

a sample collected from the rotten stumps of Juglens regia from Kotla Barog (H.P.)

has been planned with the following objectives:-

1. To work out the taxonomic details of the fungus and raise the pure

culture so as to domesticate it.

2. To evaluate different media and other physical factors conducive for

the mycelial growth.

3. To study the effect of physiological and biochemical nutritional

sources on the vegetative growth.

4. To study the utilization of different indigenous substrates for the

spawn preparation.

5. To evaluate the different local ligno-cellulosic substrates for the

cultivation of Lentinus squarrosulus (Mont.) Singer.

6. To investigate the chemical composition of the fungus.

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