Common boletus

Common boletus
Common boletus ( Boletus edulis )
Systematics
Subordination : Boletineae Family : Boletaceae (Boletaceae) Subfamily : Boletoideae Genre : Ceps ( Boletus ) Section : Porcini mushrooms ( Boletus sect. Boletus ) Type : Common boletus
Scientific name
Boletus edulis
Bull  .: Fr.

The common boletus ( Boletus edulis ), also called spruce boletus , male mushroom or noble mushroom , is a type of mushroom from the family of the thick boletus relatives and type species of the genus thick boletus . The fruiting bodies usually have a brownish hat , white to olivgelbliche pores , a bright network drawing on stem and white, rarely blue forming pressure or breach of meat . The fungus forms a mycorrhiza with numerous deciduous and coniferous trees , and it often lives in symbiosis with spruce trees . It is distributed over large parts of the northern hemisphere and was introduced by humans in some countries in the southern hemisphere . The common boletus is of great importance as an edible mushroom and is traded commercially.

features

Brown hat, long, narrow handle

Light hat, short, thick stem

The shape and color of the fruiting bodies can vary widely.

Macroscopic features

The spruce stone mushroom forms large fruiting bodies divided into a hat and a stem . The color and shape of the fruiting bodies are variable.

The hat reaches a diameter of 6 to 25, sometimes 30 centimeters. Exceptions can be significantly higher. The hat is thick-fleshed, hemispherical when young, later cushion-shaped, convex to flattened; the edge can also be bent up. Even when young, the surface is smooth and not felty, but sometimes a bit frosted and a bit slimy when wet and aged. When it is dry, the cap skin can tear open into small clods; it can hardly be removed. When young, the hat has a whitish tone, with older fruiting bodies a hazelnut or chestnut brown tone, with a yellowish or white edge always being retained; more rarely the top is colored red-brown or dark brown. Very young specimens that have grown under exclusion of light are light in color. If there is little light, the hat can remain white.

Detailed images of some features: the brown hat with a white border (1), the white stem net (2), whitish pores in younger specimens (3a) and yellow-green pores in old ones (3b) as well as the white, non-discoloring flesh (4)

The sturdy handle is between 5 and 15, in some specimens up to 20 centimeters long and reaches a diameter of two to eight or even ten centimeters at the base and two to a maximum of four centimeters at the top. Young it is usually thick and bulbous, sometimes even bigger than the hat, in older specimens it is cylindrical, bulbous or club-shaped. If there is a high layer of foliage or high moss growth, the stems can be long and thin so that the spore spread is not impaired. It was also observed that they are usually short and wide on firm ground, whereas they become narrower on soft ground. The surface is white to brownish overfiber and covered with a fine, somewhat raised white net. Most of the time this pattern only extends to about the middle of the stem and fades with age; however, it is usually retained at the tip of the handle. This development is due to the growth of the stem. Initially, the mesh pattern has the same structural dimensions as the tubes of the hymenophore . With increasing length and thickness of the stem, the net meshes widen, especially in the lower part of the stem. Since the tip of the handle grows less, the mesh remains finer and more rounded.

The flesh of young specimens is white and firm, with age it is often a bit brownish and spongy under the cap skin. It has a mild nutty taste and no particular smell. When broken or cut, it rarely or rarely turns bluish or greenish in color. The fine tubes (0.2–0.7 millimeters in diameter) are ten to forty millimeters long and, like the pores, initially colored white; they can rise above the brim, especially in old age. As the spores mature, they take on a cream-colored to green-yellow color. The tubes are bulging on the stem, can be easily removed from the hat and do not, or rarely, blue on pressure only very weakly.

Microscopic features

The spores are 12.5-17 (19) × 4.5-5.5 micrometers in size and have a spindle-elliptical shape and a smooth surface. They are tinted light greenish-yellow and provided with drops. Their spore coefficient (ratio of spore length to width) is between 2.7 and 3.5; the mean volume is 172 cubic micrometers. In potassium hydroxide (KOH) they turn pale brown and in Melzer's reagent gray green-ocher with shading, however, later ocher to pale dextrinoid (wine red coloring). The spore powder has a dark olive-brown color. The basidia are club-shaped and measure 30–47 × 8–10 micrometers. They have four or less often two sterigms without a basal buckle . In KOH they appear hyaline .

The fruiting bodies have Cheilo- and pleuro Zystiden in size from 35 to 70 x 5.5 to 10 micrometers. They are spindle-shaped, slender or bottle-shaped, rarely rather club-like and vesicular; their surface is smooth and thin-walled. They appear hyaline in KOH and pale yellow in Melzer's reagent. In addition, very variable caulocystids can be found in the network of stems, which are spindle-shaped to almost cylindrical.

The top layer of the hat consists of brown-pigmented, irregularly interwoven hyphae , sometimes 3–6 micrometer wide hyphae ends protrude, which soon settle down. In KOH it appears hyaline, gelatinous due to the lack of pigments. The hyphae below are flaky and 8 to 15 microns wide. In KOH their walls are colored ocher; in Melzer's reagent they are inamyloid (do not turn purple or black). The septa of the hyphae have no buckles. The hyphae of the tubular trama are gelatinous and partly run out from the main cord . The hymenophore is volatile amyloid.

In ectomycorrhizae, the mycelium forms a two-layer coat with a thickness of 16 to 20 micrometers each around the plant roots. The Hartigsche network is well-formed; it penetrates two cell layers of the periodontal membrane. The network is light yellow-brown to brownish in color and has irregularly distributed protruding hyphae ends. The surface of the mycelial mantle is smooth and covered with densely arranged cystids or a network of hyphae. In cross section, the edge of the jacket is compact and uneven. It is often filled with 20 micrometers long, bottle-shaped cystids that can be up to six micrometers wide at the enlarged base; they are arranged individually or in groups. Some have warty protrusions on the ends.

Species delimitation

Biliary bolete

Chestnut boletus

Gall and chestnut boletus can be similar to boletus.

In addition to the related species , the spruce stone mushroom is similar to the common bile boletus ( Tylopilus felleus ) and thick-stemmed specimens of the chestnut boletus ( Imleria badia ). A mix-up with the former is of greater importance for mushroom pickers in that a whole meal can be spoiled with a single mushroom. It is distinguished by a dark network of stems and the pores, which are pink with age; Safety brings a taste of the meat or even licking an interface. The chestnut bolet can be distinguished by a non-wetted, brownish marbled stem and, when pressed, characteristic blue tubes. Mixing it up with chestnut boletus or one of the other porcini mushrooms would not be a problem, as these species are all considered good edible mushrooms.

In North America there are a few other species that are similar to the spruce stone mushroom. Boletus variipes is mostly found in oaks , has a beige or pale yellow-brown, dry hat and the stem net is usually more pronounced. The mushroom is edible, but inferior to the spruce stone mushroom in terms of taste. Xanthoconium separans ( Boletus separans ) is characterized by yellow pores and usually a purple tone in the stem; Xanthoconium affine ( Boletus affinis ) has white to yellow, but no greenish pores and a red-brown cap with yellow spots. Both types are edible.

ecology

Symbiosis partner

Forests and forests overgrown with spruce ( Picea ) form a typical habitat for the spruce stone mushroom

The spruce stone mushroom, like the other species of the genus Boletus , is a mycorrhizal fungus that can enter into a symbiosis with numerous plant species via the ectomycorrhiza . In Europe these are primarily spruce trees, especially in the mountains, and deciduous trees such as oaks and beeches in the lowlands , as well as pine , birch , fir , hornbeam , chestnut and linden . In particular, there are including Scots pine , silver birch , stalk , grape and Quercus palustris , beech and chestnut . The spruce stone mushroom is mostly to be found in the forests, but also on the edges of the forest of the colline to montane altitude levels . Outside of forests with individual trees, in parks, gardens and similar biotopes, it is rarely found.

The mycorrhiza between the fungus and the host plant is variable throughout the life of the plant. The fungus prefers older forests between 20 and 40 years old. It occurs less often in stocks over 60 years old. Observations of forests of this age have shown that the occurrence of the spruce stone fungus can also decrease in the same forest over a longer period of time. Instead, chestnut boletus is more common in these. However, a connection with the change in the mycorrhiza has not yet been proven. One explanation can be seen in the increase in the litter and humus layer that occurs with a closed canopy ; this causes a reduction in fruiting body production (see the section Structure of the soil ). Consequently, open, sunny places are suitable for the spruce stone mushroom. The chestnut bolet, on the other hand, is a fungus that likes to occur in nutrient-rich, mineral-rich soils with a thick layer of litter and humus.

Accompaniment a

The spruce stone mushroom is often found together with the fly agaric .

The spruce stone mushroom is often found together with the fly agaric ( Amanita muscaria ) or the flour rasp ( Clitopilus prunulus ). It was also found near the pearl mushroom ( Amanita rubescens ) in East Asia, North America and some European countries . In addition, there have been reports of the common occurrence of the spruce stone mushroom with the gray amanita ( Amanita spissa ) in the Monterey pine in New Zealand. The observations suggest that other fungi influence the lifestyle of the spruce stone mushroom and that there are biological connections. So far, however, this has not been proven for any supposedly related fungus. It is therefore more obvious that the common occurrence is justified by similar soil and weather requirements of the species.

Soil claims

The fungus is mainly found in forests with acidic to neutral soil. It only occurs on a basic subsoil if it is superficially acidic. The pH value of the substrate averages about 4.2 for the top 20 centimeters; Extreme values ​​are around 3.5. Investigations with pure cultures showed that the optimal pH value for mycelium growth is somewhat higher than for fructification (fruiting). Sandy and loamy soils are also accepted and the rootability of the substrate also plays a subordinate role. The spruce stone mushroom can be found with brown earths , parabrown earths , rendzines and tendrils, among other things . On the other hand, conditions that are too dry and too humid are avoided.

Studies have shown that the amount of minerals in the soils in which the spruce stone mushroom grows can vary greatly. The only recurring characteristics are a medium to very high amount of iron and usually a high proportion of carbon and a high C / N ratio . Laboratory research has shown that carbon is essential for mycelial growth.

Some significant differences were found between the soils of the individual mycorrhizal partners: the extractable amount of iron, the available amounts of calcium and sulfur and the ratio between carbon and nitrogen in the soil of beech trees are higher than in soils without this tree species. In the soil of sessile oak the total amount of nitrogen is higher and at the same time the C / N ratio is lower than in other soils. Silver birch trees in symbiosis with the spruce stone mushroom are found on soils with a higher available amount of calcium, sulfur and organic carbon as well as a high total amount of nitrogen. The comparison with the conditions of the soil of the pine boletus ( Boletus pinophilus ) did not reveal any significant differences.

Phenology

Seasonal conditions

Fruiting bodies of the spruce stone mushroom a few days old

Evaluations of the fructification periods in different regions showed that the formation of the fruiting bodies seems to depend on a decrease in temperature and increased humidity. These conditions are met, for example, after a little rain during a warm summer and heavier rainfall in the cooler autumn. This results in the regional time spans for the appearance of the fruiting bodies.

Observations have shown that the amount of fruit bodies produced can also be lower in years with better conditions than in years with less favorable conditions. It is assumed that the cause is that sufficient nutrients and bioactive substances have accumulated in the mycelium that are sufficient for fructification. On the other hand, life cycles of the fungus could be responsible.

In Central Europe, the fruiting bodies appear sporadically from June or even in May, in larger quantities from August to around October. It can be used as often flood occur designated periods of growth, but also over several years lasting Fruktuationspausen. Stronger night frosts usually end the fructification, but in some areas individual specimens can still be found in November or December for several years.

In the UK, for example, the fruiting bodies grow between August and October. In 1991 there was largely no fructification after a dry summer and an early, dry autumn. In Christchurch , New Zealand , where fructification lasts from late February to mid-May, fruiting was interrupted in 1994 by a dry autumn. Irrigation on the University of Canterbury campus ensured a renewed growth period locally. In Northern California , fruiting body formation never begins until early November and continues through late December.

growth

The diameter of the hat can increase over two centimeters in a day; the average daily increase is around nine millimeters. Studies have shown that the fruiting bodies are relatively resistant to adverse conditions. The growth rate is mainly influenced by the minimum air and soil temperature . Because the temperatures are lowest during the night, growth is greatest during this time. The optimum relative humidity for the growth of the fruiting bodies is about 60 percent or more, the higher the humidity, the higher the growth rates. A deficit of water in the fruiting bodies that has developed over the course of a day cannot be compensated during drier nights. If the humidity is too low during the day and the temperature is too high, the fruiting bodies also grow mainly during the night; this growth can be up to three times the daily rate. Growth is interrupted at moisture levels below 40 percent. The development of the fruiting bodies also prevents prolonged dry periods , sudden drops in temperature to values ​​around zero degrees Celsius and frost .

The fruiting bodies usually grow at a distance of 1 to 2.5 meters from the trunk of the host plant. It turns out that the fruit bodies dry out faster if they are exposed to sunlight for a very long time - especially at noon. Thus, locations that are partially shaded during the day are more favorable for development. Fruit bodies that have been attacked by insect larvae tend to grow over a shorter period of time and often become slightly smaller than unaffected specimens.

Structure of the soil

Several studies have shown that removing the litter , the upper layers of humus and the herbaceous plants increases the production of fruit bodies. This fact is justified by the fact that when the material was removed, the dense and compact root system of the wire-smear was removed, which prevents the production of fruit bodies. Another reason is the decrease in the nitrogen content in the soil, which was determined during the investigation. This assumption is confirmed by observations of pine stands fertilized with nitrogen , in which a decrease in fruiting body production was determined. The amount of nitrogen in the pine needles also influenced the production of the fruiting bodies. The spruce stone can still be found in dense litter. Another study shows that such extensive removal of the soil layers reduces the number of fruit bodies produced; most of the fruiting bodies arise from minor interventions. However, it should be noted that a definite statement about a change can only be made after more than two years. There are different opinions about the effect of adding soil material; decreased or no effect on fruiting body production was observed.

Relationship with the mycelium

Studies have shown that the associated mycelium can not be found under every fruiting body . This is also the case when the fungus has formed a pronounced mycorrhiza with the corresponding tree. Fruiting bodies of the genus Boletus can be strongly represented above the surface of the earth , although they have comparatively little subterranean mycelium. The reason for this is believed to be in the ecological niche that the mushrooms occupy. These are different - depending on whether they occur in the symbiosis in the rhizosphere , in the soil or in other areas. As a result, the distribution and mass of the mycelium in the soil do not indicate the amount of fruiting bodies that will be produced. It can also be concluded from the observations that the mycelium disappears after the fruiting bodies have formed. However, this process has not yet been investigated.

Pests and feeding insects

The flesh of this fruiting body was eaten by insect larvae.

The red robin is a pest of the spruce stone mushroom. Here on a perl mushroom

The pests of the spruce stone fungus include Sepedonium chrysospermum , the secondary fruit form of the golden mold ( Hypomyces chrysospermus ). This forms an initially powdery white, mold-like coating, which then turns golden yellow and finally reddish brown. It begins at the base of the stem or the pores and then spreads over the entire fruiting body. The flesh of the spruce stone mushroom is decomposed and given a soft consistency. Gold mold is most common in years of high humidity, but even then the number of affected fruit bodies is not high. Little is known about the toxic effects of mold. In some cases, eating dried stone mushrooms caused abdominal pain that was attributed to the gold mold.

Other pests are various mushroom flies as well as other insects and their larvae . These include species of the genera Bolitobius and Atheta as well as Gyrophaena poweri , Bolitochara lunulata and the red robber ( Oxyporus rufus ), sometimes also the common dung beetle ( Geotrupes stercorarius ).

Infestation of as yet unknown virus-like particles, sometimes also referred to as viruses , causes a disease that manifests itself in relatively thick stems and small hats. The affected fruit bodies are more often attacked by maggots , bacteria and other fungi than healthy fungi. The clinical picture was first observed in 1969 and occurs mostly in regions of high humidity. The infestation results in reduced fruiting body growth, and sometimes the fruiting bodies do not form completely.

distribution

Probable distribution of the spruce stone mushroom

Natural spread

Introduced

Naturally

The spruce stone mushroom occurs naturally in the northern hemisphere in large parts of Europe as far as Morocco , in Asia, as well as in North America and Mexico .

It has a Mediterranean to Arctic distribution in Europe and occurs from northern Scandinavia to the extreme south of Italy and Greece . The fungus is common and common everywhere; in Germany it has a dense occurrence. The spruce stone mushroom can be found at all altitudes , although it is common up to the high-montane areas, but significantly less often in the planar level up to 300 meters. Only about seven percent of the occurrences are up to 350 meters above sea level. In Baden-Wuerttemberg , for example , the spruce stone mushroom has the highest occurrence of all the boletus there. There have been reports of a decline in the spruce stone mushroom, but no noticeable decline or endangerment can be determined.

In North America, the spruce stone mushroom is widespread in the United States to the west approximately to the state of Mississippi and in Maine and New Jersey in the northeast, among other places . In the Rocky Mountains it can be found up to an altitude of 3,500 meters. It can also be found in California , where it occurs in coastal forests, in dry oak forests and oak savannas, and in high mountain forests of mixed conifers and deciduous trees.

In Asia, the fungus can be found in China , among other places, where it is widespread from Heilongjiang in the northeast to the Yunnan-Guizhou plateau and Tibet in the southwest. In the latter area, the fungus can be found at altitudes between 200 and 1500 meters. It is also distributed in Hainan and Japan . The fungus is also found in the Himalayas from the northwest of the mountains via Nepal to Arunachal Pradesh in the east. In the Middle East, the distribution extends to Afghanistan in the east .

Anthropogenic

The mushroom does not occur naturally in the southern hemisphere, but it was introduced in New Zealand , South Africa , Kenya and Zimbabwe .

In New Zealand, it is mainly found in an area of ​​80 square kilometers around the city of Christchurch at an altitude range between sea ​​level and 280 meters. It was probably introduced there by European settlers over 100 years ago at the roots of oak , beech or birch , when exotic trees were planted in the Christchurch area in the mid-19th century . After that, the fungus spread in two large parks and on a Ministry of Works site and is now found in large parts of the city of Christchurch. In South Africa the spruce stone mushroom is widespread on the Cape of Good Hope and in the south of the KwaZulu-Natal Midlands at altitudes between 900 and 1500 meters. The mushroom was also introduced in Zimbabwe; probably with imported pines . It is particularly common at Stapleford and Nyangui in Manicaland Province .

In some sources, Australia is also counted among the distribution areas. In 1979 the occurrence of the spruce stone mushroom was reported on this continent. However, there is no evidence of this in the herbarium of the Royal Botanic Gardens in Melbourne . In 1996, some fruiting bodies were found in the lower part of Mount Wellington , which were initially mistaken for the spruce stone mushroom, but it turned out to be the common birch mushroom ( Leccinum scabrum ).

Systematics

The division into shapes and types has always been very difficult for porcini mushrooms . In his monograph on Röhrlinge, Franz Kallenbach is said to have repeatedly postponed the processing of the porcini mushroom, so that he was later unable to describe it. Even today, the opinions of the authors on the systematic classification of porcini mushrooms differ.

Since the spruce stone mushroom, like other closely related species, is very popular as an edible mushroom , it has received a great deal of attention not only from biologists but also from restaurateurs . As a result, numerous taxa emerged , which are often based only on one ecological characteristic, such as the mycorrhizal partner, or very variable morphological properties, such as the color of the hat. The number of species described and subordinate (intraspecific) taxa is particularly high for the taxa similar to the spruce stone mushroom. Van der Linde found in 2004 that these traits are overestimated, which was confirmed by phylogenetic analyzes in 2008; the variable properties are due to strong ecological and morphological differences within the species. These include the occurrence under deciduous and coniferous trees as well as white varieties. B. betulicola , B. persoonii , B. quercicola and B. venturii are among the species described, which should actually be subordinated to the spruce stone mushroom ( Boletus edulis ) . In terms of molecular genetics, they can hardly be distinguished from B. edulis , although they are very variable externally and in their mycorrhizal partners. In addition, there are initially defined as subordinate taxa, which are now viewed as separate species.

Other authors come to the conclusion that the macroscopic, microscopic and ecological differences of some taxa are so marked that the status on species level is justified, even if they cannot be genetically separated. This concerns u. a. B. betulicola and B. pinetorum .

External system

The flaky-stemmed witch boletus ( Boletus erytropus ) is a close relative of the spruce stone mushroom.

The spruce stone mushroom used to belong to the genus Boletus s. l. to the Boletus section , which was well separated from the rest of the genus by the white to olive color of the pores and the net markings on the stem. According to more recent phylogenetic findings, the genus Boletus was polyphyletic . The genus was therefore split up in 2014 and most species were transferred to other genera. Only the boletus remained in the genus Boletus . So far, in addition to the spruce boletus, three to five other independent species have been recognized for Europe, which were previously listed as subspecies of Boletus edulis . In 2008, they could be confirmed by molecular phylogenetic analyzes, as their molecular biological properties can be easily distinguished from B. edulis . Because the species are usually difficult to distinguish for laypeople, they are often referred to as boletus . Most of the time, the species can be distinguished with the naked eye by the differently designed hat cover layer. Three other species, which initially also belong to Boletus edulis s. l. ( B. rex-veris later to B. pinophilus , B. regineus to B. aereus ) and resemble it, can be found in North America. Three others, which can be more clearly distinguished from Boletus edulis , were also initially ascribed to him: Boletus fibrillosus , Boletus mottiae and Gastroboletus subalpinus . Other related species include the witches' Röhrlinge and the Schönfuß Röhrling ( Caloboletus calopus ).

The relationships of some selected species can be shown in a cladogram after aligning the ITS sequences of fruiting bodies and mycelium as follows .

Thick boletus ( Boletus see left )

Porcini mushrooms ( Boletus s. Str. )   Spruce stone mushroom ( B. edulis )     Pine boletus ( B. pinophilus )     Bronze bolete ( B. aereus )     Summer boletus ( B. reticulatus )     Strong- smelling boletus ( Lanmaoa fragrans )     Caloboletus calopus ( caloboletus calopus )     Flaky- stalked witch boletus ( Neoboletus erytropus )     Pink-capped boletus ( Rubroboletus rhodoxanthus )     Net-handled witch bolete ( Suillellus luridus )

Similar species of Boletus edulis that were initially subordinated to it

Art	Former names	Common names	Distinguishing features of the species from Boletus edulis	Mycorrhizal partner	Remarks	image
Boletus aereus Bull. (1789)	B. edulis var. Aereus B. edulis subsp. aereus	Bronze boletus Black-capped boletus	has an almost black-brown hat and a brownish stem, tubes stay white for a long time	Oaks , beeches and sweet chestnuts	prefers warmer regions
Boletus pinophilus Pilát & Dermek (1973)	B. edulis var. Pinophilus B. edulis subsp. pinophilus	Pine boletus Red-capped boletus	The hat and stem are red-brown in color	Pine , sometimes spruce , beech and fir
Boletus reticulatus Schaeff. (1774)	B. aestivalis B. edulis var. Reticulatus B. edulis subsp. reticulatus	Summer boletus	has a pronounced stem net and a lighter, ocher-gray hat, the surface of the hat is felty, the flesh under the hat skin is white	Oak, red beech , sweet chestnut	will appear from June, in southwest Germany from May
Boletus barrowsii Thiers & AH Sm. (1976)	B. edulis var. Barrowsii	white king bolete	Fruiting bodies somewhat larger and lighter in color, cream-colored with pink tones	Conifers, especially yellow pine	sweeter in taste, prefers warm regions: New Mexico , southern Colorado , poss. all the way west to California
Boletus regineus Arora & Simonini (2008)	B. aereus var. Regineus	queen bolete	Fruiting bodies mostly smaller, hat darker, young with whitish tones, has a sticky hat skin, the edge of the hat is not protruded by the tube layer	Deciduous and mixed forest
Boletus rex-veris Arora & Simonini (2008)	B. edulis var. Rex-veris B. pinophilus var. Rex-veris	spring king bolete	likes to grow in clusters, tends to grow underground	Conifers, especially pines	appears from the end of May

	European and North American species
	European species
	North American species

Internal system

For several decades there has been a large number of subspecies and varieties in Europe, of which the ones listed in the table above have even been confirmed as independent species . Many of the other taxa are difficult or impossible to distinguish genetically. For example, B. persoonii and B. venturii cannot be separated from B. edulis in this way . Thus, these and similar species previously described in Europe fall within the variability of Boletus edulis . The varieties differ mainly in the properties of the hat cover layer (primarily the shape of the end cells).

Intraspecific taxa of Boletus edulis (selection)

variety	synonym	Common name	Distinguishing features of the taxon from the main form	Mycorrhizal partner	image
Boletus edulis var. Albus ( Pers. 1825) Gilbert	Boletus persoonii	White boletus	like the main form, but with a completely white fruiting body	Pine and oak , on humus rich soils
Boletus edulis var. Arenarius H. Engel , Krieglst. & Dermek (1983)	Boletus arenarius		Stem base misshapen, bulbous, thickened, deeply rooted, stalk strongly grooved towards the base	Pines, on sandy soils
Boletus edulis var. Aurantio-ruber Dick & Snell (1965)			Hat in a rust-red tone, pores turn brown when injured and yellow-olive when printed, stem net pale cinnamon-red wine-colored, dark brown to black when printed	Pine trees
Boletus edulis f. betulicola Wassilkow (1948)	Boletus betulicola , Boletus betulicolus	Birch stone mushroom	usually noticeably paler, grayish-milk coffee brown or sometimes darker, hat and handle about the same color, long-handled	Birch trees
Boletus edulis var. Clavipes Peck (1889)		Yellow boletus	Hat later ocher on the edge, which is then irregularly present between the darker tones of the hat, so that the hat appears multi-colored (some specimens completely yellow when old), stem club-shaped, later cylindrical, network over large parts of the stem	Pine, mostly White Pine in the United States , sometimes birch and aspens
Boletus edulis var. Grandedulis Arora & Simonini (2008)		California king bolete	often strongly developed, pores brown to slightly reddish when ripe	especially pines, especially yellow pine
Boletus edulis var. Ochraceus A.H. Sm. & Thiers (1973)			The hat is entirely yellowish in color	Mixed forest
Boletus edulis var. Citrinus Pelt. ex E.-J. Gilbert (1931)	Boletus venturii	Lemon-capped boletus	tinted lemon yellow	unknown

meaning

etymology

The generic name Bōlētus stands for 'Röhrling' and originated from the Latin term boletus as the name for the best edible mushroom of the Romans . This expression has its origin in the Greek word bôlos , which means something like 'tuber'. The specific epithet edulis translates as 'edible'.

The common names are very different in different languages. The German name Fichtensteinpilz is based on the fact that it is mostly found under spruce trees. The name boletus arose because of the firm flesh, which is one of the hardest mushrooms. In Italian it is called porcino , which translates as 'piggy'. The origin of this name is unknown; it was already called suillus ('pig') by the Romans . The English name penny bun originated in the Victorian era and means something like 'penny bun' in German, which is attributed to the shape and color of the spruce stone mushroom. The other English name cep and the French name cèpe originated in the Gascon language from the Latin word cippus for 'stake'. The Dutch name Gewoon eekhoorntjesbrood translates as 'common squirrel bread '. The Swedish names karljohan and karljohanssvamp originated from Karl XIV. Johann , who made the spruce stone mushroom popular in Sweden from 1818 and took away people's fear of mushrooms.

Food value

Prepared porcini mushrooms

The spruce stone mushroom is one of the most sought-after and most collected edible mushrooms, with all similar species having a comparable edible value. The mushroom gained its popularity mainly due to the intense mushroom taste, which is not significantly reduced even when drying and cooking. It has firm meat that does not lose its consistency significantly even after long periods of cooking. The mushroom can be prepared in almost all ways; it is suitable for roasting, stewing and braising, but can also be dried or frozen. However, there are different opinions about raw consumption. Sometimes it is stated in the literature that the spruce stone mushroom can be eaten raw. However, if taken untreated, it has been reported to cause severe stomach pain.

The spruce stone mushroom was already valued by the Romans . But they also often used it to murder politicians or other public figures with hidden poison . In ancient times, it was believed that the spruce stone mushroom had medicinal properties such as the removal of freckles or other blemishes; an ointment made from the fungus was used to better heal dog bites . The spruce stone mushroom is also used in traditional Chinese medicine . There it is, for example, the main component of a pill to stimulate blood flow and relax muscles and joints; the fungus was also used to treat various gastrointestinal diseases. In Italy, the porcini mushroom risotto is a traditional autumn dish.

The fungus is avoided in Zimbabwe , among other places , as it is often found under pine trees there. This tree species is viewed with great caution, as it also contains poisonous mushrooms such as the toadstool ( Amanita muscaria ) and the panther mushroom ( Amanita pantherina ).

Some nutritional values ​​of fresh fruit bodies (100 g each)

Energy value	345.4 kJ (81.8 kcal)
protein	7.39 g
carbohydrates	9.23 g
fat	1.70 g
Thiamine (vitamin B 1 )	0.11 mg
Riboflavin (vitamin B 2 )	0.09 mg
niacin	6.07 mg
Pantothenic acid (vitamin B 5 )	2.64 mg
Folic acid (vitamin B 9 )	0.29 mg
Ascorbic acid (vitamin C)	4.21 mg
zinc	4.17 mg
potassium	203.25 mg
sodium	25.25 mg
iron	0.74 mg
Calcium	1.20 mg
phosphorus	22.26 mg

toxicology

In animal experiments it has been shown that the boletus can trigger the life-threatening poisoning syndrome of rhabdomyolysis when consumed in large quantities on several consecutive days . The study also applied the same to other edible mushrooms such as B. the birch red cap ( Leccinum versipelle ) shown. From Poland it is reported that rhabdomyolysis occurred in a person after multiple consumption of a mixed mushroom dish made from red caps and porcini mushrooms. Repeated consumption of large quantities of porcini mushrooms in quick succession should therefore be avoided.

Ingredients and ingredients

The amount of water contained in the fruit bodies can vary depending on the temperature and relative humidity during growth. In addition, metabolism can produce varying amounts of moisture during storage. Investigations on the fruit bodies of spruce stone mushrooms from Austria showed that they contain over 90 percent water. This proportion is about the same in all parts of the fruiting body and applies to both young and old stages of development. Analyzes of fruit bodies collected in Greece came to a value just under 90 percent. Studies on specimens in Turkey showed a water content of just over 80 percent.

The spruce stone mushroom is a very good carrier of protein; it is very similar to the best animal proteins and is particularly easy to digest. It is also rich in free amino acids.

The fatty acids contained are largely (84.5%) unsaturated, of which about half is polyunsaturated. These include linoleic acid, with 42.2 percent of all fatty acids, and linolenic acid (0.2%). Among the monounsaturated fatty acids contained is oleic acid (36.1% of all fatty acids); Saturated fatty acids include palmitic acid (9.8%) and stearic acid (2.7%).

100 grams of the meat contain an average of almost 500 milligrams of ergosterol , mainly in the hat and hymenophore, and just under 30 milligrams of ergosterol peroxide . The latter has anti-inflammatory and antiviral effects , among other things .

The spruce stone mushroom also accumulates heavy metals . In addition to toxic substances such as cadmium and lead (see the Health Aspects section ), silver (0.02–0.3%, based on dry matter and locations free from heavy metals) and gold (<0.002%) were found in the pulp of the fruiting bodies .

Yield

Basket with collected porcini mushrooms

In the fall of 1995, a swamp oak was examined in Christchurch on the grounds of the University of Canterbury , and fifty young fruiting bodies with an average weight of 30 grams were found at the same time. It is estimated that the weight of the fruiting bodies would have increased to 50 to 120 grams as it grew. Fruit bodies with a total weight of two kilograms per tree were also found in twenty-year-old silver birch trees in Christchurch. Although the yield in these cases is unusually high, annual harvests of 20 to 200 kilograms per hectare are considered realistic for cultivated crops .

cultivation

At least ten million spores are required to establish the symbiosis of the spruce-boletus with a host. On a laboratory scale, it has already been possible to infect plants with the spruce boletus, but the fungus is not able to continue to bind to the plant. Another method is to infect seedlings with the fungus and then raise them.

The process can be enhanced with abietic acid or with dried hats of the spruce boletus buried near the roots of the tree. Further research has shown that other ectomycorrhizal fungi and other soil organisms enable stable infections in the soil.

market

consumption

Dried spruce boletus at the Sagra del Fungo (mushroom festival) in Borgotaro

The worldwide consumption of boletus, which in the narrower sense concerns the spruce boletus, was estimated in 1998 at 20,000 to 100,000 tons. According to official figures, 2,387 tonnes were sold in Italy in 1988 (worth around ITL 28.1 billion ) and in the previous year in France 1,049 tonnes (around FRF 53.5 million ) and in Germany over 1,000 tonnes (over DEM 10 million ). of the mushroom consumed. However, this does not take into account mushrooms that have been collected and consumed privately or goods sold directly to restaurants, which makes up a large proportion. In Italy, the interest in boletus has decreased in recent years, but the demand is very high, so that the supply is exceeded. In addition to the countries mentioned, North America has a large consumption of porcini mushrooms.

trade

In 1988 there were over 3000 tons of porcini mushrooms on the market in France, Italy and Germany. Italy, one of the largest importers of spruce boletus mushrooms, imports mushrooms from numerous countries, including China, which accounts for around 60 percent of the imported goods, and South Africa. Large quantities also come from Romania, Serbia, Montenegro, Bosnia and Herzegovina and Macedonia. Among other things, fresh mushrooms from the southern KwaZulu-Natal Midlands were imported to Germany in order to increase the supply in winter and spring. The amount of mushrooms imported is not known. Dried mushrooms were also imported from South Africa.

There are mass-produced broken hats, dried or pickled, which are written out as spruce boletus. This often includes hats from other mushrooms, such as the common birch mushroom. In the 1970s, pickled mushrooms, which were butter mushrooms ( Suillus luteus ), were exported from Chile . In the 1990s, bile boletus ( Tylopilus ) were even found among dried boletus mushrooms from China in Italy ; the proportion was up to two percent and more, which is noticeable in the mushroom dish through a clearly bitter taste.

Commercial collecting

Romanian postage stamp from 1958 with the spruce boletus; it gives an indication of the importance of the mushroom for the country. The series was the first to show mushrooms on postage stamps.

Since the spruce boletus, like most mycorrhizal fungi, cannot be cultivated , the supply in the commercial trade depends on the collection of unplanned fruit bodies. The largest collection activity occurs in economically weaker countries, some of which also export; Countries with a strong economy, where people tend to collect for their own use, have the highest consumption with a lesser collection tradition. After the Iron Curtain was opened , exports to the states of the former Soviet Union , the Balkans and the former Yugoslavia rose sharply. Large quantities are harvested in Scandinavia, Eastern European countries, Austria, Switzerland, the USA, China, India and Indonesia.

About 20 percent of the total amount of all mushrooms collected is for private use, the rest is collected commercially. The collectors come from the low to middle income bracket and are mostly women; half are between 50 and 60 years of age.

In Poland, the spruce boletus is the most widely collected edible mushroom. In the Italian region of Casentino , a large part of the economic income comes from the harvest of this mushroom. In Germany it has been under restricted nature protection since 1986 and may only be collected in small quantities for personal use. The benchmark is one kilogram per person per day. The trade in porcini mushrooms collected in Germany is prohibited. Collecting and selling are permitted in Austria and Switzerland, but no more than two kilograms may be collected. In Austria, collecting is only allowed from June 15 to September 30 and is prohibited in Switzerland during the first seven days of each month. In Liechtenstein, a maximum of one kilogram of mushrooms may also be collected.

Market value

Depending on the quality, degree of freshness, state of preservation and season, the price can be between 10 and 200 US dollars per kilogram in the USA (1997), in Germany up to 120 marks (approx. 60 euros) and in France up to 100 francs (approx . 15 euros; 1991). In smaller markets like New Zealand, the price is as high as NZ $ 80 , but it can drop significantly if supply is high or there are large quantities of birch mushrooms to replace the spruce boletus. In Borgotaro ( province of Parma ), the most important place for the supply of mushrooms in Italy, porcini mushrooms to the value of four million euros were sold between July and September 2005.

Dried, frozen, or pickled specimens, or parts thereof, achieve the lowest price. This form of preservation also offers advantages because of the relatively small differences in quality and the possibility of year-round supply. Therefore, such mushrooms are used by manufacturers of ready meals, for example for mushroom soups or stews .

Health aspects

Imports to Germany, especially those from Eastern European countries, are examined for radioactivity , as very high levels of pollution have been found in the past; The main reason for this is the Chernobyl reactor accident in April 1986. Cep mushrooms are also radioactively contaminated in Central Europe, especially in southern Bavaria , in the Bavarian Forest and in large parts of Austria; in some cases over 10,000 Becquerel per kilogram were found. In general, however, the exposure to porcini mushrooms with mostly less than 200 becquerel per kilogram is not too high and significantly lower than, for example, chestnut boletus. In the European Union and Switzerland, the limit value for radioactive contamination is 600 Becquerel per kilogram.

Heavy metal exposure is another health risk, as boletus mushrooms are among the species that can accumulate heavy metals. 100 grams of the spruce boletus can contain between 0.1 and 0.2 milligrams of cadmium and 0.08 to 0.5 milligrams of lead . He can tolerate the pollutants because he forms phytochelatins , which bind them and thus detoxify them.

In rare cases, the spruce boletus can cause allergic reactions through inhalation , ingestion or contact , which are caused by the antibody immunoglobulin E ; this is triggered by a digestive protein. In extremely rare extreme cases, consumption of the boletus can lead to life-threatening reactions.

Remarks

1. ↑ In 1995, a fruit body weighing 3.2 kilograms with a hat diameter of 42 centimeters was found in Great Britain ; the stem was 18 inches long and 14 inches wide. Reported by
   Hall: Edible and poisonous mushrooms of the world . P. 222 ff.
2. ↑ The brown dye of the hat has not been examined chemically. Reported in:
   Julius Zellner: Chemistry of the higher mushrooms . BiblioBazaar, LLC, 2009, ISBN 1-110-26574-3 . P. 169; Scan at GoogleBooks
3. ↑ The data were determined on the basis of descriptions in the literature, the distribution of the specified host plants and the boundaries of the climatic zones. The sources given in the text served as a guide:
   • Hall et al. (1998): Ectomycorrhizal fungi with edible fruiting bodies
   • Wang et al .: Boletus edulis sensu lato . P. 227
   • Ciesla: Non-wood forest products from temperate broad-leaved trees . P. 86
   • Fischer et al .: Edible Wild Mushrooms of North America . P. 96
   • Masuka: Dynamics of mushroom ( Boletus edulis ) production in pine plantations in Zimbabwe . P. 69
   • Adhikary et al .: Edible mushrooms growing in forests of Arunachal Pradesh . P. 119
   • Giri et al .: Some Higher Fungi from Sagarmatha National Park (SNP) and its adjoining areas, Nepal . P. 68
4. ↑ The information comes from the source listed in the first column, unless otherwise stated.
5. ↑ The proportion of water here was 80.53 percent. With a higher moisture content, the nutritional values ​​contained are usually significantly lower. Comparisons with a Greek study (Ouzouni et al .: Nutritional value and metal content profile of Greek wild edible fungi ) for the respective dry weights show that the values ​​still differ considerably.

swell

literature

• Ian R. Hall, Anthony JE Lyon, Yun Wang, Liane Sinclair: Ectomycorrhizal fungi with edible fruiting bodies. 2. Boletus edulis . In: Economic Botany . tape 52 , no. 1 . New York Botanical Garden Press, 1998, ISSN  1874-9364 , pp. 44-56 .
• German Josef Krieglsteiner (Eds.), Andreas Gminder , Wulfard Winterhoff: Die Großpilze Baden-Württemberg . Volume 2: Stand mushrooms: inguinal, club, coral and stubble mushrooms, belly mushrooms, boletus and deaf mushrooms. Ulmer, Stuttgart 2000, ISBN 3-8001-3531-0 .
• Josef Breitenbach, Fred Kränzlin (Ed.): Mushrooms of Switzerland. Contribution to knowledge of the fungal flora in Switzerland. Volume 3: Bolete and agaric mushrooms. Part 1: Strobilomycetaceae and Boletaceae, Paxillaceae, Gomphidiacea, Hygrophoracea, Tricholomataceae, Polyporaceae (lamellar). Mykologia, Luzern 1991, ISBN 3-85604-030-7 .

Individual evidence

1. ↑ Edmund Michael: Handbook for mushroom friends . Volume 1. 5th revised edition. Fischer, Stuttgart 1983, ISBN 3-437-30436-4 . P. 318
2. ↑ Ewald Gerhardt: FSVO manual mushrooms . BLV, Munich 2006, ISBN 3-8354-0053-3 . P. 360
3. ↑ ^{a b} Andreas Gminder: Manual for mushroom collectors. Identify 340 species of Central Europe with certainty . Kosmos, Stuttgart 2008, ISBN 978-3-440-11472-8 . P. 74
4. ↑ ^{a b c d e f} Alexander H. Smith, Harry D. Thiers: The boletes of Michigan . The University of Michigan Press, 1971. p. 372 ( online )
5. ↑ Ewald Gerhardt: Porcini mushrooms, chanterelles and mushrooms. Collect and prepare the most popular mushrooms . BLV, Munich 1998, ISBN 3-405-15448-0 . P. 10
6. ↑ ^{a b} Eberhard Steiner: Reconstruction of the fruiting body development of Boletus edulis Bull .: Fr. Diploma thesis. Innsbruck 2003. p. 53
7. ↑ ^{a b c} Katharina Bickerich-Stoll: mushrooms. Definitely . J. Neumann-Neudamm, 1980, ISBN 3-7888-0337-1 . P. 100
8. ↑ ^{a b c d} Rudolf Winkler: 2000 mushrooms simply identify . AT-Verlag, Aarau 1996, ISBN 3-85502-531-2 . P. 43
9. ↑ Steiner: Reconstruction of the fruiting body development of Boletus edulis Bull .: Fr. S. 41
10. ↑ Meinhard Moser : Small cryptogam flora . Volume IIb / 2 Basidiomycetes, part 2 The boletus and leaf mushrooms (Polyporales, Boletales, Agaricales, Russulales) . 5th edited edition. Fischer, Jena 1983. p. 69
11. ↑ Steiner: Reconstruction of the fruiting body development of Boletus edulis Bull .: Fr. S. 71
12. ↑ ^{a b c d} J. Breitenbach et al .: Pilze der Schweiz . P. 54
13. ↑ ^{a b c d e f} Krieglsteiner et al .: Die Großpilze Baden-Württemberg . P. 246
14. ↑ Steiner: Reconstruction of the fruiting body development of Boletus edulis Bull .: Fr. S. 40
15. ^ Smith, Thiers: The boletes of Michigan . P. 372 f.
16. ↑ ^{a b} Smith, Thiers: The boletes of Michigan . P. 373
17. ^ Y. Wang, L. Sinclair, IR Hall, ALJ Cole: Boletus edulis sensu lato. A new record for New Zealand . In: New Zealand Journal of Crop and Horticultural Science . 1995 Vol. 23: 227-231. P. 229 ( Online PDF, 1.8 MB)
18. ↑ Lüder: Basic course mushroom determination . P. 359
19. ↑ Ewald Gerhardt: BLV identification book mushrooms . P. 34
20. ^ Smith et al .: The boletes of Michigan . P. 369
21. ^ David L. Spahr: Edible and Medicinal Mushrooms of New England and Eastern Canada . North Atlantic Books, Berkeley 2009, ISBN 1-55643-795-1 . P. 106 f. ( Scan on GoogleBooks; for the entire paragraph)
22. ↑ Hervé Chaumeton: Mushrooms Central Europe . (Original French title: Les champignons de France .) Fischer, Stuttgart 1987, ISBN 3-437-30540-9 . No. 118
23. ^ Beugelsdijk et al .: A phylogenetic study of Boletus section Boletus in Europe . P. 2 f.
24. ↑ ^{a b c d} Wang et al .: Boletus edulis sensu lato . P. 227
25. ^ E. Salerni, C. Perini: Experimental study for increasing productivity of Boletus edulis sl in Italy . In: Forest Ecology and Management . 201 (2-3). 2004. pp. 161-70. doi: 10.1016 / j.foreco.2004.06.027 . P. 166
26. ↑ ^{a b} Salerni et al .: Experimental study for increasing productivity of Boletus edulis sl in Italy . P. 169
27. ↑ ^{a b c} J. Baar, CJF Ter Braak: Ectomycorrhizal sporocarp occurrence as affected by manipulation of litter and humus layers in Scots pine stands of different age . In: Applied Soil Ecology . 4 (1). 1996. pp. 61-73. P. 71
28. ↑ Rita Lüder: Basic course mushroom determination. A practical guide for beginners and advanced users . 1st edition. Quelle & Meyer Verlag, Wiebelsheim 2007, ISBN 3-494-01341-1 . P. 358
29. ↑ U. Peintner, M. Iotti, P. Klotz, E. Bonuso, A. Zambonelli: Soil fungal communities in a Castanea sativa (chestnut) forest producing large quantities of Boletus edulis sensu lato (porcini): where is the mycelium of porcini ? In: Environmental Microbiology . 9 (4), 2007. pp. 880-889. doi: 10.1111 / j.1462-2920.2006.01208.x . P. 881
30. ↑ ^{a b} Peintner et al .: Soil fungal communities in a Castanea sativa (chestnut) forest producing large quantities of Boletus edulis sensu lato (porcini) . P. 880
31. ↑ ^{a b c d e f g h i j k l m n o p q r s t} Ian R. Hall, Anthony JE Lyon, Yun Wang, Liane Sinclair: Ectomycorrhizal fungi with edible fruiting bodies. 2. Boletus edulis . In: Economic Botany . tape 52 , no. 1 . New York Botanical Garden Press, 1998, ISSN  1874-9364 , pp. 44-56 .
32. ^ Wilhelm Mair: Investigations on mycelium growth and fruiting body formation in Boletus Edulis Bull. Ex Fr. Dissertation. Innsbruck 1974. pp. 33, 72
33. ↑ Mair: Investigations on mycelial growth and fruiting body formation in Boletus Edulis Bull. Ex Fr. p. 72
34. ^ J. Kasparavicius: Influence of climatic conditions on the growth of fruit bodies of Boletus edulis . In: Botanica Lithuanica . 7 (1). 2001, pp. 73-78. ISSN  1392-1665 . P. 77 (for the entire paragraph)
35. ^ Gerhardt: FSVO manual mushrooms . P. 360 f.
36. ↑ Kasparavicius: Influence of climatic conditions on the growth of fruit bodies of Boletus edulis . P. 74 ff. (For the entire paragraph)
37. ↑ Kasparavicius: Influence of climatic conditions on the growth of fruit bodies of Boletus edulis . P. 75 f. (for the entire paragraph)
38. ↑ Salerni et al .: Experimental study for increasing productivity of Boletus edulis sl in Italy . P. 168. There, referring to
    J. Baar, Th. W. Kuyper: Litter removal in forests and effect on mycorrhizal fungi . In: DN Pegler, L. Boddy, B. Ing, PM Kirk: Fungi of Europe. Investigation, Recording and Conservation . Royal Botanic Gardens, Kew 1993. pp. 275-286
    J. Baar, FW de Vries: Effects of manipulation of litter and humus layer on ectomycorrhizal colonization potential in Scot pine stands of different age . In: Mycorrhiza . 5. 1995. pp. 267-272
    J. Baar, CJF ter Braak: Ectomychorrhizal sporocarp occurrence as affected by manipulation of litter and humus layers in Scots pine stands of different age . In: Applied Soil Ecologie . 4, 1996. pp. 61-73
39. ↑ ^{a b c} J. Baar et al .: Ectomycorrhizal sporocarp occurrence as affected by manipulation of litter and humus layers in Scots pine stands of different age . P. 70
40. ↑ Krieglsteiner et al .: Die Großpilze Baden-Württemberg . P. 247
41. ↑ Salerni et al .: Experimental study for increasing productivity of Boletus edulis sl in Italy . P. 168
42. ↑ J. Baar, FW de Vries: Effects of manipulation of litter and humus layer on ectomycorrhizal colonization potential in Scot pine stands of different age . In: Mycorrhiza . 5. 1995, 267-272. doi : 10.1007 / BF00204960 .
43. ↑ Peintner et al .: Soil fungal communities in a Castanea sativa (chestnut) forest producing large quantities of Boletus edulis sensu lato (porcini) . P. 885 (for the entire paragraph)
44. ↑ ^{a b c} Goldschimmel ( Memento of the original from September 4, 2016 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. . Mushroom expert Harry Andersson's website 
45. ↑ M. Kuo: Hypomyces chrysospermus . February 2004
46. ↑ Michael Wood, Fred Stevens: California Fungi. Hypomyces chrysospermus . At: MykoWeb
47. ↑ D. Lunghini, S. Onofri, L. Zucconi: Some cases of intoxication probably caused by Sepedonium spp. infecting fruiting bodies of some species of boletus . In: Micologia Italiana . 13 (1). 1984 1/37-1 / 38. ISSN  0390-0460 (Italian)
48. ↑ L. Benick: Mushroom beetles and beetle mushrooms. Ecological and statistical studies . Acta Zoologica Fennica 70, Helsingforsiae 1952. p. 214
49. ↑ H. Huttinga, HJ Wichers, A. Dieleman van Zaayen: Filamentous and polyhedral virus-like particles in Boletus edulis . In: Netherlands Journal of Plant Pathology . 81, 1975. pp. 102-106. doi: 10.1007 / BF01999860 . P. 102.
50. ↑ ^{a b} Krieglsteiner et al .: Die Großpilze Baden-Württemberg . P. 248
51. ^ David W. Fischer, Alan E. Bessette: Edible Wild Mushrooms of North America. A Field-To-Kitchen Guide . University of Texas Press, Austin 1992, ISBN 0-292-72080-7 . P. 96 ( Scan on GoogleBooks)
52. ^ ^{A b} Ian Robert Hall: Edible and poisonous mushrooms of the world . Timber Press, 2003, ISBN 0-88192-586-1 . P. 224 ( Scan on GoogleBooks)
53. ↑ A. Giri, P. Rana: Some Higher Fungi from Sagarmatha National Park (SNP) and its adjoining areas, Nepal . In: Scientific World . 5 (5). 2007. pp. 67-74. P. 68
54. ↑ RK Adhikary, P. Baruah, P. Kalita, D. Bordoloi: Edible mushrooms growing in forests of Arunachal Pradesh . In: Advances in Horticulture and Forestry . 6. 1999. pp. 119-123. P. 120
55. ^ ^{A b c} William M. Ciesla: Non-wood forest products from temperate broad-leaved trees . Volume 15 of the series Non-wood forest products . Food & Agriculture Organization, Rome 2002, ISBN 92-5-104855-X . P. 86 ( Scan on GoogleBooks)
56. ^ ^{A b} A. Vizzini, A. Mello, S. Ghignone, C. Sechi, P. Ruiu, P. Bonfante: Boletus edulis complex: from phylogenetic relationships to specific primers . In: Pagine di Micologia . 30, 2008. ISSN  1122-8911 . Pp. 49-52. P. 50
57. ↑ Wang et al .: Boletus edulis sensu lato. A new record for New Zealand . P. 230
58. ↑ ^{a b c} A. J. Masuka: Dynamics of mushroom ( Boletus edulis ) production in pine plantations in Zimbabwe . In: JASSA, Journal of Applied Science in Southern Africa . 2 (2). 1996. pp. 69-76. P. 69
59. ↑ ^{a b c} H. Jahn: The summer boletus Boletus edulis subsp. reticulatus (SCHFF.) BOUD . In: Westphalian mushroom letters . Volume 1. pp. 68-72. Recklinghausen. P. 1 ( online ; PDF; 270 kB)
60. ↑ ^{a b} D.CM Beugelsdijk, S. van der Linde, GC Zuccarello, HC den Bakker, SGA Draisma, ME Noordeloos: A phylogenetic study of Boletus section Boletus in Europe . Persoonia 20, 2008. doi: 10.3767 / 003158508X283692 . P. 1 ( online ( memento of the original from July 27, 2011 in the Internet Archive ) Info: The archive link has been inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this note .; PDF; 353 kB) 
61. ↑ ^{a b c} Beugelsdijk et al .: A phylogenetic study of Boletus section Boletus in Europe . P. 6
62. ^ M. Korhonen, K. Liimatainen, T. Niskanen: A new boletoid fungus, Boletus pinetorum , in the Boletus section Boletus from Fennoscandia (Basidiomycota, Boletales). Karstenia 2009, 49 (2). Pp. 41-60. ISSN  0453-3402 .
63. ↑ Lüder: Basic course mushroom determination . P. 166
64. ↑ David Arora: California Porcini: Three New taxa, Observations on Their Harvest, and the Tragedy of Commons No . Department of Forest Science, Oregon State University. P. 357 ( online ; PDF; 782 kB)
65. ^ Vizzini et al .: Boletus edulis complex . P. 48
66. ↑ ^{a b c d e f g h} Ewald Gerhardt: BLV destination book mushrooms . Weltbild, Augsburg 2003, ISBN 3-8289-1673-2 . P. 26
67. ↑ Ettore Bielli: Mushrooms. A comprehensive guide to identifying and collecting mushrooms . Italian original title: Funghi . Kaiser, Klagenfurt 2002, ISBN 3-7043-2179-6 . P. 154
68. ↑ Bielli: Mushrooms . P. 159
69. ↑ ^{a b} H. Jahn: The summer boletus Boletus edulis subsp. reticulatus (SCHFF.) BOUD . P. 2
70. ↑ Markus Flück: Which mushroom is that? 3. Edition. Kosmos, Stuttgart 2009, ISBN 978-3-440-11561-9 . P. 121
71. ^ Vizzini et al .: Boletus edulis complex . P. 51
72. ↑ Bielli: Mushrooms . P. 164
73. ↑ ^{a b c d e} Thomas J. Volk: Tom Volk's Fungus of the Month for August 2004. Boletus barrowsii, Chuck Barrows' bolete ( Memento of the original from October 3, 2008 in the Internet Archive ) Info: The archive link was automatically inserted and still Not checked. Please check the original and archive link according to the instructions and then remove this notice. . University of Wisconsin-La Crosse, 2004 
74. ↑ Orson K. Miller, Hope Miller: North American Mushrooms. A Field Guide to Edible and Inedible Fungi . Falcon Guide, 2006, ISBN 0-7627-3109-5 . P. 392
75. ^ Vera Stucky Evenson: Mushrooms of Colorado and the Southern Rocky Mountains . Big Earth Publishing, 1997, ISBN 978-1-56579-192-3 . P. 157 ( Scan on GoogleBooks)
76. ↑ ^{a b} Michael Wood, Fred Stevens: California Fungi. Boletus regineus . At: MykoWeb
77. ↑ Michael Wood, Fred Stevens: California Fungi. Boletus edulis . At: MykoWeb
78. ↑ ^{a b c} Arora: California Porcini . P. 358
79. ^ ^{A b c} Michael Wood, Fred Stevens: California Fungi. Boletus rex-veris At: MykoWeb
80. ^ Beugelsdijk et al .: A phylogenetic study of Boletus section Boletus in Europe . P. 3
81. ↑ Krieglsteiner et al .: Die Großpilze Baden-Württemberg . P. 245 f.
82. ↑ ^{a b} Beugelsdijk et al .: A phylogenetic study of Boletus section Boletus in Europe . P. 2
83. ^ Rose Marie Dähncke: 1200 mushrooms . 2nd Edition. AT Verlag, 2009, ISBN 978-3-03800-485-1 . P. 81
84. ^ Smith, Thiers: The boletes of Michigan . P. 375 f.
85. ↑ ^{a b} Timothy J. Baroni, Ernst E. Both: Boletus edulis var. Aurantioruber . Boletes of Central New York
86. ↑ Dähncke: 1200 mushrooms . P. 83
87. ↑ Marcel Bon : Parey's book of mushrooms . Parey, Hamburg 1988, ISBN 3-490-19818-2
88. ^ Smith, Thiers: The boletes of Michigan . P. 374 f.
89. ↑ ^{a b} Edible mushrooms ( Memento of the original from July 22, 2010 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. . Website of the mushroom expert Harry Käding 
90. ↑ Timothy J. Baroni, Ernst E. Both: Boletus clavipes . Boletes of Central New York
91. ↑ Arora: California Porcini . P. 358 ff.
92. ^ Smith, Thiers: The boletes of Michigan . P. 373 f.
93. ↑ Contents of mushroom magazine The Tintling
94. ↑ Helmut Genaust: Etymological dictionary of botanical plant names. 3rd, completely revised and expanded edition. Birkhäuser, Basel / Boston / Berlin 1996, ISBN 3-7643-2390-6 , p. 102 ( scan from GoogleBooks).
95. ↑ To be precise: Etymological dictionary of botanical plant names . P. 222
96. ^ Jacob Grimm , Wilhelm Grimm : German Dictionary . Volume 18. Hirzel, Leipzig ( online )
97. ↑ F. Werneburg: The boletus, Boletus edulis Bull. The witch's mushroom, Boletus luridus Schaeff. The field agaric , Psalliota campestris L. The tuber agaric , Amanita phalloides Fr. In: Yearbook of the Association for Scientific Pedagogy . 17, 1885, pp. 238-250. P. 240
98. ^ ^{A b} Antonio Carluccio : The Complete Mushroom Book. Savory Recipes for Wild and Cultivated Varieties . Quadrille, London 2003, ISBN 978-1-84400-040-1 . P. 36
99. ↑ Carluccio: Mushrooms . Collection Rolf Heyne, Munich 2004, ISBN 3-89910-231-2 (translation of the English original edition). P. 36
100. ^ Henry W. Fowler (ed.), Della Thompson (arr.): The Concise Oxford Dictionary . Clarendon, Oxford 1998, ISBN 0-19-861320-2 . P. 213
101. ↑ K. Monday: Porcini mushroom. Boletus edulis . At: www.tintling.com
102. ↑ DG Spoerke, BH Rumack: Handbook of mushroom poisoning. Diagnosis and treatment . CRC Press, Boca Raton 1994, ISBN 0-8493-0194-7 . P. 11 ( Scan on GoogleBooks)
103. ^ Ciesla: Non-wood forest products from temperate broad-leaved trees . P. 87
104. ↑ Examples are Lüder: Basic course mushroom determination . P. 358 and Bielli: mushrooms . P. 153
105. ↑ B. Lian, J. Zang, W. Hou, S. Yuan, DL Smith: PCR-based sensitive detection of the edible fungus Boletus edulis from rDNA ITS sequences . In: Electronic Journal of Biotechnology . 11 (3). 2008. doi: 10.2225 / vol11-issue3-fulltext-4 ( full text )
106. ^ Carluccio: The Complete Mushroom Book . P. 166
107. ↑ N. Çaglarlrmak, K. Ünal, S. Ötles: Nutritional value of edible wild mushrooms collected from the Black Sea region of Turkey . In: Micologia Aplicada International . 14 (1). Pp. 1-5. P. 3 f.
108. ^ P. Nieminen, M. Kirsi, AM Mustonen: Suspected myotoxicity of edible wild mushrooms . In: Exp. Biol. Med. (Maywood) . tape 231 , no. 2 , 2006, p. 221-228 .
109. ↑ P. Chawaluk: Rhabdomyolysis as an unsepcific symptom of mushroom poisoning - a case report . In: Przeglad Lek. No. 70 , 2013, p. 684-686 .
110. ↑ PK Ouzouni, KA Riganakos: Nutritional value and metal content profile of Greek wild edible fungi . In: Acta Alimentaria . 36 (1). 2007, pp. 99-110. doi: 10.1556 / AAlim . 36.2007.1.11 . P. 103
111. ↑ Steiner: Reconstruction of the fruiting body development of Boletus edulis Bull .: Fr. S. 56
112. ↑ Ouzouni et al .: Nutritional value and metal content profile of Greek wild edible fungi . P. 104
113. ↑ Çaglarlrmak et al .: Nutritional value of edible wild mushrooms collected from the Black Sea region of Turkey . P. 3
114. ↑ H. Fink, KW Hoppenhaus: Strange observations in the determination of the biological protein quality of boletus (Boletus edulis) and champignon (Psalliota bispora) in dietary and therapeutic terms. A contribution to alimentary liver necrosis in rats . Natural Sciences , Vol. 43, 1956 (June). ISSN  1432-1904 . Pp. 133-134. P. 134
115. ↑ B. Ribeiro, PB Andrade, BM Silva, P. Baptista, RM Seabra, P. Valentão: Comparative Study on Free Amino Acid Composition of Wild Edible Mushroom Species . Journal of Agricultural and Food Chemistry , 56 (22), 2008, pp. 10973-10979 doi: 10.1021 / jf802076p .
116. ↑ K. Pedneault, P. Angers, A. Gosselin, RJ Tweddell: Fatty acid composition of lipids from mushrooms belonging to the family Boletaceae . In: Mycological Research . 110 (Pt 10). 2006. pp. 1179-1183. doi: 10.1016 / j.mycres.2006.05.006 . P. 1182
117. ↑ P. Kalač: Chemical composition and nutritional value of European species of wild growing mushrooms: a review . In: Food Chemistry . 113 (1). 2009. pp. 9-16. doi: 10.1016 / j.foodchem.2008.07.077 . P. 14
118. ↑ W. Krzyczkowskia, E. Malinowskaa, P. Suchockib, J. Klepsa, M. Olejnikd, F. Herold: Isolation and quantitative determination of ergosterol peroxide in various edible mushroom species . In: Food Chemistry . 113 (1). 2008. pp. 351-355. doi: 10.1016 / j.foodchem.2008.06.075 . P. 354
119. ↑ Kalač: Chemical composition and nutritional value of European species of wild growing mushrooms . P. 13
120. ↑ ^{a b} E. R. Boa: Wild edible fungi: a global overview of their use and importance to people . Volume 17 of the series Non-wood forest products . Food & Agriculture Organization, Rome 2004, ISBN 92-5-105157-7 . P. 97 ( Scan on GoogleBooks)
121. ^ Hall: Edible and poisonous mushrooms of the world . P. 225
122. ↑ Boa: Wild edible fungi . P. 96 f.
123. ^ N. Sitta: Presenza di funghi del genere Tylopilus frammisti a funghi porcini secchi importati dalla Cina e commercializzati in Italia . Micologia Italiana . 29 (1). 2000. pp. 96-99. ISSN  0390-0460 . P. 98
124. ↑ Boa: Wild edible fungi . P. 89
125. ↑ ^{a b} Boa: Wild edible fungi . P. 96
126. ^ Ciesla: Non-wood forest products from temperate broad-leaved trees . P. 86
127. ↑ Regulation on food mushrooms (Regulation VSp). Amendment of March 27, 2002 (PDF; 61 kB). Federal Department of the Interior
128. ↑ ^{a b} Mag. Freydis Burgstaller-Gradenegger: On the subject of mushroom picking from a legal point of view. Carinthian Nature Conservation Act, Mushroom Ordinance, Forest Act ( Memento of the original dated June 2, 2013 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. (PDF; 140 kB) 
129. ↑ ^{a b} Nature Conservation Ordinance (NSchV) ( Memento of the original dated February 1, 2010 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. . Government Council of the Canton of Bern. November 10, 1993 
130. ↑ Mushroom collection regulations in Switzerland ( Memento of the original from September 14, 2010 in the Internet Archive ) Info: The archive link has been inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. . Swiss Association of Official Mushroom Control Bodies, March 2010 
131. ↑ Radiation exposure from fungi?  ( Page no longer available , search in web archives )  Info: The link was automatically marked as defective. Please check the link according to the instructions and then remove this notice. (PDF; 386 kB) State Office for Consumer Protection, Agriculture and Land Reorganization. P. 1  
132. ↑ Chernobyl study: 1,700 fatalities in Austria . Science.ORF.at, April 20, 2006
133. ↑ Stiftung Warentest : Wild mushrooms. Fungi and radiation . test.de September 23, 2010
134. ↑ Radioactivity and radiation in Austria 2005 and 2006. Data and evaluation . Republic of Austria, BMG Section III, BMLFUW Section V, May 2009. p. 57
135. ↑ Karin Wurzbacher: 18 years after Chernobyl. EU limit values ​​and radioactive contamination of foodstuffs ( Memento of the original from June 13, 2010 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. . From the members' magazine Umweltnachrichten, issue 99 / April 2004. Umweltinstitut München eV 
136. ↑ Environmental radioactivity and radiation doses in Switzerland. Annual report 2015  ( page no longer available , search in web archives )  Info: The link was automatically marked as defective. Please check the link according to the instructions and then remove this notice. . P. 84  
137. ↑ Stiftung Warentest: Mushrooms. Devil stuff and hellish pleasure . test.de, August 30, 2001 (accessed: December 28, 2012)
138. ↑ Ouzouni et al .: Nutritional value and metal content profile of Greek wild edible fungi . P. 107
139. ↑ C. Collin-Hansen, SA Pedersen, RA Andersen, E. Steinnes: First report of phytochelatins in a mushroom. Induction of phytochelatins by metal exposure in Boletus edulis . In: Mycologia . 99 (2), 2007. pp. 161-174, PMID 17682769 .
140. ↑ A. Helbling, N. Bonadies, KA Brander, WJ Pichler: Boletus edulis. A digestion-resistant allergen may be relevant for food allergy . In: Clinical and Experimental Allergy . 32. Bern 2002. pp. 771-775. P. 771

Web links

Commons : Common boletus ( Boletus edulis )  - album with pictures, videos and audio files

Wiktionary: Fichtensteinpilz  - explanations of meanings, word origins, synonyms, translations

• Michael Kuo: Boletus edulis . The king bolete. In: MushroomExpert.com . 2001, accessed December 8, 2012 . 
• Alexander H. Smith, Harry D. Thiers: The boletes of Michigan . In: University of Michigan Herbarium Fungus Monographs . The University of Michigan Press, 1971, pp. 372-377 ( available online ).
• David L. Spahr: King Bolete. In: Mushroom-Collecting.com . 2009, accessed December 8, 2012 . 
• Michael Wood, Fred Stevens: California Fundi: Boletus edulis . In: MykoWeb . Retrieved December 8, 2012 . 

Please note the instructions for collecting mushrooms !

This version was added to the list of articles worth reading on May 25, 2010 .