User:Green168/sandbox/Life-skill and Talent

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[1]1.1 Mushrooms and Mushroom Biology It has been well known that the 20th century has been an explosive time for the accumulation of knowledge. Modern technology for human civilization is expanding every day. However, human beings still face and will continue to face three basic problems: shortage of food; pollution of the environment; and diminishing quality of human health, due to the continued increase of the world population. Macrofungi (mushrooms) not only can convert these huge lignocellulosic biomass wastes into human food, but also can produce notable immune enhanced products, which have many health benefits. Another significant aspect of mushroom cultivation is using the biota in creating a pollution-free environment. 1.1.1 Definition of a Mushroom Mushrooms with other fungi are something special in the living world, being neither plants nor animals. They have been placed in a kingdom of their own called the kingdom of Myceteae. But what are mushrooms? The word mushroom may mean different things to different people and countries. It has emerged that specialized studies and the economic value of mushrooms and their products had reached a point where a clear definition of the term “mushroom” was warranted. In a broad sense “Mushroom is a macro-fungus with a distinctive fruiting body, which can be either epigeous or hypogeous and large enough to be seen with naked eye and to be picked by hand. Thus, mushrooms need not be basidiomycetes, nor aerial, nor fleshy, nor edible. Mushrooms can be ascomycetes, grow underground, have a non-fleshy texture and need not be edible. This definition is not a perfect one but can be accepted as a workable term to estimate the number of mushrooms on the earth. The most common type of mushrooms is umbrella shaped with a pileus (cap) and a stipe (stem) i.e. Lentinula edodes. Other species additionally have a volva (cup) i.e. Volvariella volvacea or an annulus (ring) i.e. Agarius campestris or with both of them i.e. Amanita muscaria. Furthermore, some mushrooms are in the form of pliable cups; others round like golf balls. Some are in the shape of small clubs; some resemble coral; others are yellow or orange jelly-like globs; and some even very much resembles the human ear. In fact, there is a countless variety of forms. The structure that we call a mushroom is in reality only the fruiting body of the fungus. The vegetative part of the fungus, called the mycelium, comprises a system of branching threads and cord-like strands that branch out through soil, compost, wood log or other lignocellulosic material on which the fungus may be growing. After a period of growth and under favourable conditions, the established (matured) mycelium could produce the fruit structure which we call the mushroom. Accordingly mushrooms can be grouped into four categories: (1) those which are fleshy and edible fall into the edible mushroom category, e.g., Agaricus bisporus; (2) mushrooms which are considered to have medicinal applications, are referred to as medicinal mushrooms, e.g., Ganoderma lucidum; (3) those which are proven to be, or suspected of being poisonous are named as poisonous mushrooms, e.g., Amanita phalloides; and (4) a miscellaneous category which includes a large number of mushrooms whose properties remain less well defined, which may tentatively be grouped together as ‘other mushrooms’. Certainly, this approach of classifying of mushrooms is not absolute and not mutually exclusive. Many kinds of mushrooms are not only edible, but also possess tonic and medicinal qualities. Mushrooms are devoid of leaves, and of chlorophyll-containing tissues. This renders them incapable of photosynthetic food production. Yet, they grow, and they produce new biomass. How? For their survival, for their growth, and for their metabolism, they rely on organic matter synthesized by the green plants around us, including organic products contained in agricultural crop residues. The organic materials, on which mushrooms derive their nutrition, are referred to as substrates. Mushrooms are a unique biota which assembles their food by secreting degrading enzymes and decompose the complex food materials present in the biomass where they grow, to generate simpler compounds, which they then absorb, and transform into their own peculiar tissues. These substrate materials are usually by-products from industry, households and agriculture and are usually considered as wastes. And these wastes, if carelessly disposed of in the surrounding environment by dumping or burning, will lead to environmental pollution and consequently cause health hazards. However, they are actually resources in the wrong place at a particular time and mushroom cultivation can harness this waste/resource for its own beneficial advantage. Mushrooms lack true roots. How then are they anchored into the substrates where we find them? This is affected by their tightly interwoven thread-like hyphae, which also colonise the substrates, degrade their biochemical components, and siphon away the hydrolysed organic compounds for their own nutrition. 1.1.2 Mushroom Hunting Fungi are found just about everywhere. Mushrooms, a special group of macro-fungi, are rather more selective than other fungi in that the size of the fruiting body requires the availability of more nutrients than are required for the production of asexual spores by micro-fungi. In damp places, such as tree-fern ecosystems and tropical rain forests, plentiful moisture leads to abundant mushroom formation. There, mushrooms can be collected at most times of the year. But in drier regions, they occur only after seasonal rains. In these ecosystems there may be a particular flora of mushroom species associated with the seasons of autumn, summer and spring. Relatively few mushrooms are produced during the cold winter months, although there are perennial fruiting bodies that persist during the winter. The formation of mushroom fruiting bodies depends very much on the pattern of rains and, in some years, there may be virtually total lack of mushroom fruiting. Mushroom hunters, in addition to carrying along with them the basic equipment and field guide references, which will vary depending on personal requirements and regional conditions, should record such items as date, time, location, smell, substrate (host) colour, habitat and anything at all unusual about the specimen. Some important characteristics for identification disappear rapidly as the mushroom matures. These characteristics have to be recorded accurately at the time of collection. 2.1.3 Ecological Classification of Mushrooms Ecologically, mushrooms can be classified into three groups: the saprophytes, the parasites and the symbiotic (which include mycorrhizal) species (Fig. 1). There are only a few parasitic mushrooms. Most of the cultivated gourmet mushrooms are saprophytic fungi. Some of the edible mushrooms are mycorrhizal species, e.g. Perigold black truffle, Tuber melanosporum, and matsutake mushroom, Tricholoma matsutake. It is difficult to bring these highly celebrated wild gourmet species into cultivation because they are mycorrhizal. These species have a symbiotic relationship with some vegetation, particularly trees, i.e. there is a relationship of mutual need. Saprophytes obtain nutrients from dead organic materials; parasites derive food substances from living plants and animals and causing harm to the hosts; and mycorrhiza live in a close physiological association with host plants and animals – thereby forming a special partnership where each partner enjoys some vital benefits from the other. However, some mushrooms do not fall neatly within these man-made categories and can share two of these categories. For example, some Ganoderma spp. including G. lucidum are common saprophytes, however they can be pathogenic too; also Tricholoma matsutake, while initially appearing to be mycorrhizal on young roots, soon becomes pathogenic and finally exhibits some saprobic ability.



Cantharellus Tricholoma cibarius matsutake; Tubur melanosporum



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