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| Fungi are ubiquitously present in air, water, soil and organisms, or on organism surfaces. Fungi are very diverse taxonomically with many different species. They are diverse in size from invisible yeasts, which are only several microns in diameter, to extremely large polypores, which may grow up to several meters in diameter. Although diverse in species as well as in form, fungi share some common characteristics, which are summarized as follows: |
| (1). |
Fungi are eukaryotic organisms. Compared to other eukaryotic plants or animals, fungi have relatively very small nuclei, containing very few nucleotides in their genomes. For example, the amount of nucleotides in mushrooms is eight times that in E. coli bacterium (a prokaryote), but is only one percent of that in humans. |
| (2) |
Fungi live heterotrophically as saprophytes, parasites or mutualists. Unlike animals, which ingest and then digest, fungi secrete digestive enzymes onto a food source nearby, dissolve it to smaller soluble molecules and then ingest them into cells. |
| (3) |
Fungal cells have cell walls, which are composed mostly of chitin. |
| (4) |
Most fungi consist of hyphae, which combine to make up the fungal mycelium. (Yeasts, which are unicellular and grow reproductively by some type of budding or fission, are an exception.) Fungi can reproduce sexually or asexually by spores that grow from hyphae. |
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| Some of the fungi familiar to people are used in fermentation, such as Saccharomyces sp., which can be used to make bread or wine and only can be seen with microscope. Some members of order Mucorales (Zygomycota) are used to make fermented soy beans. Rhizopus sp. that grows on old bread are also members of Zygomycota. Penicillin, widely used in medicine, is made from Penicillium sp., a member of Mitosporic fungi. Many edible fungi, such as Lentinusedodes (Berk.), Agaricus bisporus and auricularia, are members of Basidiomycota. In addition to their use as food and medicine, fungi are also important players in nature. Many fungi, such as wood-rotting fungi and Piloboous sp., participate in the decomposition process of bio remains or organic matters, accelerating the cycle and use of natural substances. Some fungi are parasitic and may cause diseases. For example, cordyceps sinensis is the host insect of Cordyceps sp. Ganoderma sp. lives on trees parasitically and causes damage to them. Many fungi form mutually-beneficial symbiotic relations with other life forms. For instance, lichens, commonly seen in the forests or woods, are symbiotic life forms consisting of fungi and algae. Root systems of a vast majority of seed plants and members of Endogonaceae may form endomycorrhiza relationship, which enhances the ability of plants to absorb nutrients from the soil. Many species of fungi form ectomycorrhiza relationship with plants. In short, fungi of various kinds play an important role in both natural ecosystems and our daily life. However, our knowledge of them is still quite limited. The book introduces members of Ascomycota and Basidiomycota in the hope that the general public can know more about them and more students can be inspired to joint the research work of this biological field. |
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| Protista |
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Myxomycota |
| Fungi |
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| Chytridiomycota |
| Zygomycota |
| Ascomycota |
| Basidiomycota |
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| Myxomycota： |
The life cycle of myxomycota is divided into two stages. Plasmodia are a mass of small protoplasm. They are saprophagous and motile. When mature, they grow into immobile sporangia and contain numerous spores and capillitia. They usually live on rotten logs or fallen leaves. |
| Chytridiomycota： |
They are mostly aquatic, tiny, saprophagous or parasitic. In their life cycle, they produce zoospores with a single flagellum. |
| Zygomycota： |
Their sexual reproduction occurs with the fusion of two gametangia to form a zygosporangium, which then produces thick-walled zygospores, such as Rhizopus sp. And Entrophospora.
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| Ascomycota： |
Their sexual spores are produced in the ascus and are thus called ascospoers, such as Saccharomyces sp., Cordyceps sp. and Morchelella sp. |
| Basidiomycota： |
Their sexual spores are produced in the basidium and are thus called basidiospores, such as auricularia, Lentinusedodes (Berk.) and ganoderma sp. |
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Procedure of Specimen Production |
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Records and Identification of Specimens |
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Field collection data include location, elevation, growth environment, substrata, collector, time, collection number. Take location records as detailed as possible. It's better to include the longitude and latitude of the location measured by GPS as well because the name of a place may change with time but its longitude and latitude will never change.
 Both macro- and micro- characteristics are recorded. Macro-characteristics are features that are visible by naked eyes or dissecting microscopes, such as the shape, size, color, texture, surface change, smell, taste and so on. Micro-characteristics are those that can be seen only through optical microscope, such as the shape, size, color and chemical reaction of hypha, cystidia, paraphyses, basidia, asci and spores.
There are only few experts in any specific group of fungi so unidentifiable specimens can be mailed in one or several bundles to experts for identification. There are several things that need to be paid attention to when consulting experts:
- It's better to get approval from the expert you intend to consult first.
- Don't mail too many specimens in one time (for example, no more than 10 copies) unless you have obtained approval from that particular expert.
- Specimens should be mailed along with complete collection information and numbers.
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Cultural Research Methods |
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Acquisition of Fungal Strains
Fungal strains for research can be obtained in three ways:
- Mycelia (FB) can be obtained from the wood substrata where the fruiting bodies grow or from the internal tissues of fruiting bodies. The mycelia obtained from either ways are regarded identical.
- Monosporous mycelia (MS) and Polysporous mycelia (PS) can be obtained from germinated basidiospores which grow in MEA petri dishes several days after the spore print is diluted successively and spread in the petri dishes.
- Mycelia can be obtained through germinated spores which are isolated under an inverted microscope.
Cultural Research
 The cultural description and cultural codes of wood fungi are made according to the system used by Nobles (1965). The system was modified by Boidin and Lanquetin (1983) and then minor modifications were made to it by other mycologists (Chamuris et al, 1986). The Nobles system detailed by Nakasone (1990) was complete and adopted by the mycologist of the Museum. According to the system, mycelia are grown on 1.5% MEA instead of 1.25%. The cultural temperature is 25¢J instead of room temperatures. Non-wood fungi are also grown on 1.5¢MMEA. Phenoloxidase tests are carried out with gallic acid agar (GAA) and tannic acid agar (TAA) while tyrosinase tests are carried out with tyrosine agar (TYA) (Nakasone,1990). Growth rate tests are made at different temperatures, namely 10, 15, 20, 25, 30, 35 and 40¢J. The rates are measured every two days for a 14 successive days.
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| | Common Identification Reagents and Their Formula | | | | | | | - KOH (3-5 % KOH)：
It is used on dried specimens to make their micro-characteristics look similar to what they look like in the field. Phloxine (1%) may be added to KOH to dye the specimen. - Lactophenol：
It is often used to identify ascomycota. It is made with 20ml of phenol, 20ml of lactic acid, 40ml of glycerol and 20ml of distilled water. - Melzer's solution：
It is formulated by 0.5g of Iodine, 1.0g of KI, 22g of HCL and 20ml of distilled water. Melzer's solution can turn amyloid to blue and dextrinoid to red-brown. It can be used to test various characteristics. - Sulfuric benzaldehyde：
This reagent is used to check the reaction of sticky cystidia. The solution will turn blue-black if there is cystidia (SA+). If there is no change in color of the reagent, there is no cystidia (SA¡Ð). The reagent is made with an addition of 5ml of pure sulfuric acid to 1.5ml of distilled water, and then pour in 4.5ml of benzaldehyde after the solution become cool. When making this formula, please note that the sulfuric acid must be poured into water very slowly to avoid overheating or explosion. | |
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