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Environment GROW MORE MUSHROOMS DO NOT EAT TOADSTOOLS
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ENVIRONMENT

GROW MORE MUSHROOMS DO NOT EAT TOADSTOOLS

By M. MITHAL JISKANI
Assistant Professor (Plant Pathology)
Sindh Agriculture University, Tandojam
April 29 - May 05, 2002

Mushroom is a form of plant life but has no green coloring matter or chlorophyll. It is being recognised as fleshy fungi, sometimes tough, umbrella like fruiting body, produces microscopic spores, which serve as a mean of reproduction, but are not same as that of plant seed. Naturally, the mushrooms observed during the rainy season on the manure heaps and dump places; grown in places like fields, woods, forests, water channels, manure heaps, bunds and on grassy grounds or in the plains, with abundance of humus as saprophyte and primary decomposer or on living trees or plants as parasite.

Undoubtedly, it is hard to say that how many kinds of fungi or even mushrooms are? There may be several kinds or species of mushrooms. Some are extremely poisonous known as toadstools. The majority are unattractive for eating (commonly called non edible) because of poor flavour, taste, texture or small size or sometimes due to unattractive colour and shape. Still other species are poisonous to some people and harmless to other; and a few are not only edible, but delicious too. Poisonous mushrooms are known to be poisonous because someone ate them and become ill or died. White edible mushrooms are known to be edible because people have eaten them regularly in quantity with no ill effect.

The word toadstool is a distortion of the German word 'Todestuhl', which means death chair. The edible higher fungi are called mushrooms but the poisonous are termed as toadstools. For the other and more common belief of the origin of the word toadstool may clear from the figure" (Dube, 1993 "An introduction to fungi"). Or, it may also to say that they go by this name because of disgust, loathing, abhorrence from the people due to its non-edibility and not pleasing or uninteresting size, shape, colour or so.

Over 10 million different kinds of organisms (livings) inhabit earth. To discuss and study these organisms, scientists have classified each kind and group of the species in categories. Less than one third of earth's species has been catalogued and given names.

The earliest classification system recognised only two kingdoms of livings. Animal kingdom and Plant kingdom. Plant kingdom is divided into two main divisions: phanerogams (flowering plants ) and cryptogams (non-flowering plants). The cryptogams are further classified into three main grourps viz. lower cryptogams known as thallophyta (include algae, fungi and bacteria), higher cryptogams known as bryophyta (mosses) and pteridophyta (ferns). Whilst most biologists now use the five kingdom system, falling into two superkingdoms. Prokaryonta (include only one kingdom monera the bacteria) and Eukaryonta (include four kingdoms: animalia-animals, plantae-plants and trees, mycetae-fungi and protista-algae and other single celled organisms). Both recognised classification systems did not show mushrooms/toadstools (or fungi) under kingdom of flowers. That is an other way by which mushrooms sometimes are termed as fungus flowers, which actually because of their lovely shapes and colours as well as their delicacy, nutritional and medicinal values.

In the same way, there are thousands of mushroom varieties found throughout the world. About 2500 species are reported to be edible (hence are not known/termed as toadstools). So far only 20 species are very popular. The mushrooms, have commercial value, are: white button mushrooms or crimini or portabellaor portobello (Agaricus bisporus). Oyster mushrooms include different species of Pleurotus, Chinese mushrooms include different species of Volvariella. Morels (Morchella esculentia) are also common in use.

CULTIVATION: There are several methods of mushroom cultivation with only little difference or modification. The mushrooms do not need direct sun light and open field for cultivation like other crops, because these are independent of sun light. The mushrooms absorbs oxygen and exhales carbondioxide like animals; but this does not mean that these grow only in dark. Different artificially cultivated mushrooms need different range of temperature, humidity, light and ventilation. The oyster mushroom must require light for growth and development. In fact, the mushrooms are one of the most difficult commodities to grow. Intensive labour is required to produce a consistent, high quality crop. Also, mushroom farms today are highly technical operations complete with extensive computerised system to monitor each point in production.

It is also pertinent to mention here that the simple, economical and commercial methodology for cultivation of some known edible mushrooms (discussed above) have been evolved, but most of us are unknown to this!? While nature has gifted most suitable environmental conditions from sea level to high mountains, where various kinds of mushrooms grow naturally and different edible mushrooms could easily be grown round a year, by changing mushroom species time by time or by controlling temperature, humidity, light and ventilation on a whole as per requirement. Otherwise, the mushrooms can not be grown year after year with full commercial excess, unless proper growing conditions are provided and adequate facilities are available, for better crop yield through control of different diseases and insect pests.

The mushrooms require less space, less care, less equipment and expenditure for cultivation, than most of the plants and animals. The area and production of different crops for the year 1998-99; may indicate that a huge quantity of the crop wastes, are easily available at low cost, which could be converted in to edible mushrooms(Table).

BUTTON MUSHROOM: The white button mushrooms, resembles the shape of button, therefore mostly known as button mushroom, but because it is naturally grown in meadow, therefore it is also called meadow mushroom, while in Europe, it is known as European mushroom, town or street mushroom. It is largely grown and greatly consumed throughout the world with almost 80 per cent share among growing mushrooms. This mushroom is difficult to cultivate and need many more expenses than other artificially cultivated mushrooms. Rice husks or wheat grains found to be the best for spawn preparation of button mushroom. It needs different types of composts with different compositions for cultivation. 4-6 air changes or introducing 10 cubic foot fresh air (ventilation) per square foot bed area per hour are necessary for good crop. 80 to 95% humidity, 15 to 25C temperature and time to time watering is also its basic requirement for normal growth and development.

OYSTER MUSHROOM: The oyster mushroom is second most popular. This mushroom resembles the shape of shellfish, therefore mostly known as oyster mushroom, but it is also called as wood mushroom, dhingri, henda, kharari, shooto, meat of the forest, sadafnuma khumbhi, sipi khumbhi etc. It can be consumed as a fresh as well as dried. This mushroom is most easy to cultivate and need less expenses and care than other artificially cultivated mushrooms. Best spawn can be prepared on sorghum (jowar) and other cereal grains. Mostly the wheat, paddy, barley, oat and gram straw, banana, sugarcane and maize leaves, empty millet heads and corn cobs, cotton waste, small and thin sticks and boll locules, sugarcane bagasse, banana pseudostems, saw dust, logs, waste news papers, manure etc. can be utilised as substrate (medium) for cultivation. This mushroom require 80 to 100% humidity, 20 to 30C temperature and white florescent light for growth and development.

CHINESE MUSHROOM: The chinese mushroom stood third popular mushroom. Perhaps, the cultivation of this mushroom started in China, because of which, it is known as chinese mushroom as well as tributary mushroom or nanhua mushroom. It is grown best on paddy straw, therefore it is called paddy straw mushroom. This mushroom also can be consumed as fresh as well as dried. Different agricultural and industrial straw waste, recommended for the cultivation of oyster mushroom, can be used for spawn preparation and cultivation of chinese mushrooms, but paddy straw proved to be the best. This mushroom requires 80 to 100% humidity, 25 to 35C temperature and at least two time watering for cropping.

CONCLUSION

Everybody can cultivate mushrooms but the growers can play a vital role, to convert agricultural and industrial waste (the plant residue, waste of forestry and agricultural as well as industrial waste and other refuse, rubbish or trash) into a substrate by cultivating mushrooms, to produce beneficial food and effective medicine.

Table: The area and production of different crops for the year 1998-99 may indicate that a huge quantity of the crop wastes, is easily available at low cost, which could be converted in to edible mushrooms.

Crop

Area (000 hectares)

Production (000 tonnes)

Wheat

8.230

17.856

Rice

2.424

4.674

Millet (Bajra)

463

213

Sorghum (Jowar)

383

228

Maize

962

1.665

Barley

137

137

Gram

1.077

698

Sugarcane

1.155

55.191

Cotton

2.923

1.495 (8.790 '000 Bales)

Banana

95

Source: Economic Survey 1999-2000, Govt. Of Pakistan.