The Fungal Kingdom

The living world is boundlessly vast, fascinating and complex, and even today it is full of mysteries. To make it easier to find one's way through its expanses, scientists have divided this world into a dozen or so kingdoms. A fairly understandable, acceptable and still relevant classification of the living world is that of the English scientist Whittaker (Whittaker, 1969), in which three kingdoms are distinguished according to their mode of nutrition: plants (300 thousand species), fungi (about 1.3 million) and animals (about 1.5–1.7 million).

The world of fungi is one of the largest and least known. Today about 100–300 thousand species have been described, and it is believed that only one in every 5 species has been described. That means there are far more of them.

Unlike plants, nature did not give fungi the miraculous synthesising pigment chlorophyll, thereby limiting their ability to produce organic substances from carbon dioxide and water by harnessing the enormous resources of solar energy. As a result, like other heterotrophic organisms, they were forced to make use of already existing organic matter through direct assimilation. In the course of evolution, fungi have taken excellent advantage of this offer from nature.

Fungi can be found throughout the whole of the earth, wherever there is organic matter. Their wide ecological amplitude is determined by a combination of morphological, physiological and adaptive traits formed over a long evolution. Besides the places with the most suitable living conditions for fungi to thrive (forests, parks, gardens, soil), they are found in the most unexpected places – in the permafrost zone, deep dark underground spaces, caves and grottoes, in mountains above the clouds, in arid deserts and in the depths of the oceans.

In fact, fungi are not so immobile or feeble; at times they are even quite menacing and frightening. Farmers, gardeners, flower growers and foresters are almost constantly confronted with diseases caused by parasitic fungi that inflict a host of losses.

When Fusarium diseases cut down the life of winter crops in the root-collar zone, the damage only becomes visible in spring, when strips of yellowed patches appear in fields of green shoots. Even if a grain does grow, however meagre, it is fit neither for food nor for fodder. The leaves and fruits of cabbages, potatoes, tomatoes and other vegetables are devastated by anthracnose. No less fierce, only harder to notice, are the Verticillium wilts, which choke plants by wilting them. And then there are the "nice" scabs, rusts, smuts and especially powdery mildews – how much damage they do, or how completely they destroy fruit, cereals, vegetables or the seedlings of a future forest. It is hard even to calculate. A great many people and animals suffer from them (especially in warm countries).

What is more, there are many accounts of parasitic fungi that, having got into libraries, museums and archive repositories, mercilessly destroy valuable works of art, books and documents that have survived for centuries or longer while satisfying their vital needs, and damage the most valuable equipment. They wreck houses, break down bridges and help sink ships. These fungi were spoken of with particular ill will by sailors of old, whose wooden ships they often sank. Of course, if a person is prudent and resourceful, the door is closed to dangerous fungi and the losses they cause are small.

On the other hand, many fungi produce valuable medicinal and nutritional substances: antibiotics, vitamins, growth stimulants, enzymes, organic acids, proteins, phosphorus, potassium, etc. Physicians and pharmacologists have long been interested in this; for example, penicillin alone, which has saved millions of lives, exalted fungi as if atoning for the harm done by its kin, drawing special attention to them. About 1000 fungal compounds with antibacterial and antiviral properties or biological activity are currently known, and their medicinal properties are being intensively studied.

Biologists (foresters, farmers, gardeners) have taken an interest in beneficial fungi that destroy insects – and even fungi – harmful to field, orchard, vegetable-garden and forest crops. They successfully make use of their services. It would be hard to imagine the life of bread and pastry bakers, all cooks, brewers and winemakers without yeasts. And what wonderful work fungi do in the soil, loosening it and enriching it with humus.

And the forest (which has sheltered man since time immemorial, clothed him, fed him and protected him from misfortune) is a complex living organism in which harmony and order between plants, animals and especially fungi have been established over millions of years. The forest and fungi are like inseparable twins that cannot live without each other. Every year from 2 to 10 tonnes or more of needles, leaves, twigs, branches and fallen trees fall onto each hectare of forest litter. Here fungi, as the initiators of lignin decomposition, occupy an exceptional place – they are nature's true sanitation workers. Aided by the sun, rain and bacteria, protozoa, insects and other small animals, within a few years or even sooner they turn not only fallen debris but also windthrown trees, stumps and even fine construction timber left unattended into loose forest soil. Some literature sources claim that as many as 80 percent of plant species could not grow well without symbiosis with fungi, or would even languish.

For example, orchids would not even be able to put out a seedling without a fungus, and perhaps even today people would never have seen the flowers of these wonderful plants.

And ceps, orange birch boletes, saffron milkcaps, chanterelles and many other edible and poisonous fungi grow only in the shelter of oak or birch, pine or spruce and certain other trees.

So fungi, one might say, are part of the very organism of the forest and remain important both to the forest and to man. And in the overall cycling of matter in nature they take an active part not only in the decomposition of organic matter, but also in its renewal.

Paleomycologists claim that the first, simplest fungi appeared on earth at the dawn of living organisms (in the Archaean era), approximately 800 million years ago, and mycorrhizal fungi 265 million years ago.

The world of fungi is large and diverse. Fungi vary greatly in size – from those invisible to the naked eye to those weighing a dozen or even several dozen kilograms – and in way of life. Their diversity and distribution are particularly poorly studied. However, macromycetes, and especially cap mushrooms, perhaps because they are larger and more visible, are the best studied of the fungi. In Lithuania about 2500 species of macromycetes have been recorded.