Pleurotus euosmus Berkeley apud Hussey Saccardo

Mushroom Growing 4 You

Growing Mushrooms at Home

Get Instant Access

Cantharellus Cibarius Mycelium
Figure 278. P. euosmus mycelia 3 and 10 days after inoculation onto malt extract agar media.

Introduction The Tarragon Oyster mushroom is closely related to Pleurotus ostreatus. According to Watling & Gregory (1989), this mushroom is generally considered a form or varidQl of P. ostreatus. but differ in the strong smell of tarragon. It has been reported, to date, from England and Scotland. P. euosmus behaves, in culture, similarly to P. ostreatus

Common Names: The Tarragon Oyster Mushroom.

Taxonomic Synonyms & Considerations: Pleurotus euosmus can be distinguished from P. ostreatus by its odor (tarragon) and by spore size. The spore size of P. euosmus is 12-14 p substantially'arger than the 7.5-1 1 p spores of the European P. ostreatus collections. However. I would not be surprised that these taxa are found to be conspecific through interfertility or DNA studies. Hilber (1989) suggests synonymy between these two taxa without elaboration. The morphology of this mushroom—v ith its depressed cap at matun'y and long running gills—bears strong resemblance to Pleurotus ostreatus.

Pleurotus eous (Berkeley) Saccardo is a discretely separate species from P. euosmus and ;s more closely allied to the pink P. djamorv arieties than to the gray brown P. ostreatus and allies. (See Pegler (1972) and Corner (1981)). Chang & Miles make reference to nutritional analysis of "Pleurotus eous" in Edible Mushrooms & their Cultivation (1987 pg. 28) without further elabor?f;on. See also the taxonomic discussions of P. djamormdP. ostreatus.

center Mushroon/beige-tan at first, becom- (■

times absent. ^

M^roscopic Features: Spores pale pinkish li lac, oblong and narrow, measuring 12-14x4-5 |

p. Otherwise similar to P. ostreatus. Figure 279. P. euomus fruiting from pasteurized

Available Strains: Strains are available from wheat straw, some 3ritish, European and American culture

TZt\ Characteristics: White, longitudinally tinear cottony, aenal fast growinjand classically

SSe SooiSrcolomzin; a/etndishof YPA, the mycelium tears off in thick sheets.

Yagrance Signature: Sweet, pleasant, shghtly anise-.ike, virtually identical to /> estreatu

'ikely to pro u ~e rod, asly using the Natural Culture techniques describe, m this book. „ y , , Pmirsps for Exn^-sion of Mycelial Mass to Achieve Fruiting: Transfer cultures duced directly i to pasteurized straw or ste -/zed sawdust. Suggested Agar Culture Media: MYA, MYPA, PDYA or OMYA.

2nc ar Generation Spawn Media: Gram spawn for the first two generations, hardwood sawdust spawn for the final stage many more substrate materials given modest experimentation.

Spawn Run:

Incubation Temperatures: 70-80° F. (21-27° C.) Relative Humidity: 98-100% Duration: 7-14 days C02:>10,000 ppm. FreshAir Exchanges: 0-1 perhour Light Requirements: n/a r'rimordia Formation:

Initiation Temperature: 65-75° F. (18-24° C.) Relative Humidity: 95-100 % Durat' ^n: 7-10 days C02:< 2000 ppm FreshAir Exchanges: 4-8 perhour Light Requirements: 750-1500 lux. Fruitbody Development:

Temperature: 70-80° F. (21-27° C.) Relative Humidity: 90-95% Duration: 4-8 days. C02:< 1000 ppm FreshAir Exchanges: 4-8 perhour Light Requirements: 750-1500 lux.

Cropping Cycle:

3 crops two weeks apart.

Recommended Containers for Fruiting: Bags, bottles, columns and trays

Yield Potentials: 75-100% biological efficiency, greatly affected by the size of the mushrooms at harvest, and the number of flushes allowed.

Harvest Hints: Mushrooms should be harvested before heavy sporulation. Since this mushroom strongly resembles Pleurotus ostreatus in terms of biology and appearance, the same guidelines for picking should be followed.

Form of Product Sold to Market: Fresh, dried and powdered.

Nutritional Content: 25% crude protein; 59% carbohydrates; 12% fiber, 9% ash; and 1.1% fat

MedLinal Propert :s: Not known to this author. Probably similar to P. ostreatus.

Flayor, Preparation & Cooking: Versatile and flavorful, tins mushroom can be incorporated into a wide variety of recipes. I prefer to saute young mushrooms at high heat in a light oil and to add cash ews or almonds along with onions to adorn white fish or salmon which .s then baked. Please refer to the recipes in Chapter 24.

Comments' The cultivation of Pleuwtus euosmus parallels the cultivation of P. ostreatus and grows f^ZJt^ZL range, not requin ag a cold shock to initiate. The cultures in my collection nroduce uniform medium sized fruitbodies specific to puncture holes in the containers. Clusters of 5-

-rely numbenng more, with the majority£ *e reaching full maturity. These features may be strain specific. Please refer to the discussion of r. ostreatus, a close relative and possible future synonym of this mushroom.

Pleurotus ostreatus (Jacquin ex Fries J Kummer

Malt Extract Agar Recipe
^igure 280. P. ostreatus mycelia 4 and 10 days after inoculation onto malt extract agar media.

Introduction: The prototypic Oyster mushroom, Pleurotus ostreatus has long been a favorite of mushroom hunters, especially in the spring time in lowland, hardwood forests. A prolific producer on a wide array of substrates, strains of this species are plentiful and easy to grow. Enjoying a worldwide reputation, specimens of extraordinary size have been collected from the wild. For instance, in the fall of 1988 near the north coast of Sicily, Salvatore Terracina, a farmer, collected a P. ostreatus nearly 8 ft. in circumference, 20 inches thick, and weighing 42 lbs! For the prepared and astute cultivator, cloning tliis monsier could have resulted in an extraordin? ily productive strain.

Common Names: The Oyster Mushroom. Oyster Shelf, Tree Oyster Straw Mushroom

Hira ake (Japanese for "Flat Mushroom") Tamogitake (Japanese)

Taxonomic Synonyms & Considerations: Pleurotus ostreatus is the type species for the Genus Pleurotus and represents ahuge complex of subspecies, varieties and strains. Comparisons w;th other taxa is compounded by the fact many strains labelled as P. ostreatus are in fact P. pulmona :us and vice versa. For a mushroom so widely cultivated T am surprised (and relieved) that only recently has the taxonomy become clearer, largely through the works of Petersen, Vilgalys and Hilber.

Pleurotus ostreatus is so similar to P. pulmonarius that they are difficult to separate macrcscopi-cally. The western collections of Oyster mushrooms on conifer usually fall .nto P. pulmonarius

species concept. Furthermore, whn P. pulmonarius is found wild in the west, it pre fers the higher altitude, drier coniferous forests to the hardwood, river-bottoms where P. ostreatus dominates. Furthermore, P. pulmonarius is primarily found in the spring to early summer whereas P. ostreatus is common from the spring through late fall. A recently named species, P. populinus Hilber & Miller has a marked preference for black cottonwood (.Populus trichocarpa) and aspen (Populus tremelloides and P. tridentata) Unlike P. ostreatus, P. populinus has, according to Vilgalys et al. (1993), a buff-colored, non-lilac spore print and larger spores, measuring 9-12 x 3-5 p.

An Oyster strain from Florida. Pleurotus florida Eger is considered by this and other authors to be a synonym of P. ostreatus because Figure P ostreatus mycelium 21 days after inspores from each species are cross fertile, the oculation.

Z1S a variety P. Jus ilber (1982) noted that ft original stram o Eger tMa Slnterfertllew,thK nreatu,Vilgalys(1993)concnrswi . alter,bn soleyon,th K DNA comparisons. In our book, The Mi kroon Culler <■ ^ W« incorrectly ggested synonymy between P.floi la and P. flondanus. the latter being a distinctly eenarate snecies moved to the Genus Lentinus by Pegler (1983). . . , ,

Z he*rmes bluisl Oyster mushroom called Pleurotus columbinus is also in doubt as a senaratelv™ species iuger proposes Pleurotus columbinus to be a variety of P ostreatus, i.. P. XSu v r vhmbZs (Quel apud Bres.) Quel Tms placement concurs wilti the long held v!ev 4

of this variety is its nearl perfect, even ca marginandbn dlyconvex X ¿e North An :an Pleurotus sapidus also shares synonymy with P. ostreatus, accordmg to

^ Unles^coinparaf' re DNA techniques are employed, or interfertility studies between known spe-cie^ are conducted, mistaken i entifications between these taxa are likely. Those cloning wild snecimens are1 erefore encourage to retai dried specimen for future venfic ation of identifica-

tio^ Formore information, piea Lonsul I ,er (1982), Kay & Vilgalys (1992). Petersen & Hughes

Description: Cap convex at first expanding to broadly convex, eventually flat and even upturned in age 5-20 cm. (+) in diameter. White to yellow to grayish yellow to tan, rarely wiifi pinkish tones, to lilac gray to gray-brown. Cap margin smooth to undulating like an Oyster shell. Color varies according to the strain, lighting, and temperature conditions. Stems are typically eccentrically attached to the cap. Flesh generally thin. Some strJns form clusters; others form individuals.

Distribution: Distributed throughout the temperature and tropical forests of the world

Natural Habitat: Common on broad-leaf hardwoods in the spring and fall, especially cottonwoods, oaks, alders, maples, aspens, ash, beech, birch, elm, willows and poplars. (From an evolutionary point of view, this mushroom has been very successful, given its ability to saprophytize a broad range of tree species.) Although seen on dying trees, P. ostreatus is thought to be primarily a saprophyte, but behaves as a facultative parasite at the earliest opportunity. Occasionally occurring on composting bales of straw, and in Mexico, on the waste pulp from coffee production. (The occurrence of P. ostreatus on this last habitat might be a result of this species escaping from the woodland environment and taking advantage of a niche provided by the coffee industry.) P ostreatus, and particularly P. ostreatus var. columbinus, are occasionally found on conifers, especially Abies. The most abundant fraitings of this species is in low valley riparian habitats

Microscopic Features: Spores white* to slightly lilac to lilac grey, 7.5-9.5 x 3-4 ¡a. Clamp connections present. Context monomuic.

Available Strains: The genome of strains for this species is vast and increasingly explored by home and commercial cultivators. Cold and warm weather strains are available from numerous culture libraries. Amycel's #3001 and Penn State's # MW44, cold weather strains, are popular. A warm weather strain I cloned from mushrooms growing on a fallen oak in a ravine near San Diego, oroduces an attrac five, white mushroom in as short as 10-12 days from inoculation onto wheat straw. (See Figure 285)

* From my experiences, Oyster mushrooms from river-bottom habitats in western Washington and Oregon produce a white to grey buff spore print, and not distinctly lilac as reported for the eastern forms. Furthermore, I have recently collected a pale rose variety of P. ostreatus on alder (Alnus rubra) from western Washington which I have never encountered before. The paie rose color has been described for P. pulmonarius, but not for P. ostreatus.

Pleurotus Euosmus
Figure 282. A sporeless strain of P. ostreaius. Under the microscope, the gill planes are entirely free of basidia.
Texas Mushroom Strain PrimordiaPleurotus Euosmus

Figure 283. A dark, cold weather stram ot r. Figure same column 24 hours later. Musn ostreatm fruiting 21 lays after inoc, .don onto rooms are ready for harvest, wheat straw. Note primordia form specific to punctures in plastic.

The same strain produces a brown capped mushroom at cold temperatures, a reaction typi( J of most Oyste^ar -ties. "Spore-less" strains have obvious advantages for indoor cult, ion e cigly f th long gestation penod before fruiting can be shortened. (See Igure 282). One sporeless sttan available from the Fren ,-based Somycel coirpany is # 3300. For, lore information on sporeless strams, and how to develop them, consult the article by Imbernon & Laoarere (1989).

Mycelial Characteristics: Whitish, longitudinally radial, soon becoming cottony, ir ige form irig a thick tenacious mycelial ia Age mycelium often secretes yellowish to orangish droplets of a metabolite which is a toxin to nematodes. This metabolite deserves greater study

Fragrance Signature: Sweet, rich, pleasant, distinctly anise and almost almond-like.

Natural Method of Cultivation: On logs or stumps outdoors Pagony (1973) reported that, on aver-ag more an 1 b. of mushrooms per yephalted fto,.inoculated poplar stump^ mor than 3 years. Of the 200 poplar stumps, ranging in size from 6-17, nches that were ino^late in the spring all produced by the fall of the follov tag year. As expected, hardwoods of greater density, such , O. to c longer to produce but sustained yields for a greater penod.

Recommended Courses for Expansion of Mycelial Mass «chief e Fruiting: g D-^ain-to-cerea' straw, or agar-tc f ; ^-supplemented, sterihzed sawdust. Since dds n room - under liquu. cal tare conditions, wn gen^ted by these methods is highly recommended. See Chapter D.

Suggested Agar Culture Media: MYPA, PDYA, OMYA or DFA. Optimal growth seen at pH 5.5-6.5

1st, 2nd & 3rd Generation Spawn Media:

Rye, wheat, milo, sorghum, corn, & millet. Sawdust spawn is not needed for indoor cultivation methods. However, sawdust spawn is ideal in the inoculation of stumps and logs in outdoor settings growth parameters 317

Pleurotus Eunosmus

Figure 285. A white Oyster variety of P. ostreatus isolated from southern California that fruits 10 days from inoculation onto wheat straw.

Substrates for Fruiting: A wide array of agn cultural and forest waste products can be used, including but not limited to: straw (wheat, rye, oat, rice, and barley straw); corn stalks, sugar cane bagasse; coffee pulp; banana waste; cotton waste & cottonseed hulls; hardwood sawdusts; paper by-products; soybean waste; palm oil by-products; agave waste; and even the pulp remaining from tequila production! The pH at make-up can vary between 6.0-8.0 but should fall to an optimum of 5.0 at fnr.ing for maximum biomass production. (See El-Kattan etal., 1990.)

Martinez et al. (1985) reported yields of 132% biological efficiency (4 flushes) from coffee pulp that was fermented for 5 days, pasteurized, and inoculated with wheat grain spawn. Further, they found residual caffe'ne from the spent substrate was reduced by more than 90%. (Caffeine represents a significant toxic waste to streams in coffee growing regions of the world.) Mar.inez-Carrera (1987) validated the results wilh yields in excess of 100% biological efficiency on the same substrate and presented the first model for utilizing this abundant waste product.

Piatt et al. (1982) published studies on the utility of cotton straw as a substrate for this mushroom Their yields average 600-700 grams per kilogram of dry cotton straw, in other words 60-70% biological efficiency.

Figure 285. A white Oyster variety of P. ostreatus isolated from southern California that fruits 10 days from inoculation onto wheat straw.

YieJd potentials: 75-200% biological efficiency, greatly affected by the size of the fruitbodies harvested, and the number of flushes orchestrated.

Harvest Hints: Mushrooms should be picked when young, and preferably in clusters. Once the gills produce abundant spores, storageability rapidly declines. Workers should wear filter masks effective down to 7 microns to eliminate the inhaling of spores. Mushroom surfaces should be slightly dry at harvest. Mushrooms should be cl lied first to 35° F. (1-2° C.) and then placed into end-user containers (for restaurants or consumers) and covered v/ith breathable an i-condensate plastic film.

Form of Product Sold to Market: Fresh and dried mushrooms. Waste straw substrate has been test marketed as a cattle feed. .

Nutritional Content: Crude protein: 10-30%. Vitamins ( : 30-144 mg/100 g; Niacm: 109 mg/lOOg SSSOO g- Hrgh in potassium: 306 mg/100 g^ For further information, see Bano &

Raiarathnam (1982), Miles & Chang (1986), andRr et al. (1988).

Medicinal Properties: Recent studies (Gunde-Cimerman et al., 1995) show that Pleurotus ostreatus fnd orrJoX a d spec.s naturally produce Lovastalin ®(3^hydroxy-3-methylgluta^coen-7vme A reductase) a drug approved by the FDA in 1987 for treating excessive bloo, cholesterol M^re Lovastatfn is present in toe caps than in the stems, more concentrated on the mature gills, and Mpeciahy^&e spores .This compound and others related to it may explain the often reported cholesterol-lowering effects of many woodland mushrooms.

When mice were implanted with Sarcoma 180, the tumors were inhibited by mc r5 than 60% after —= ) The Oyster mushrooms constituted 20% of their daily diet. Oyster mush-rnomsfieureas a' relatively minor player, comparatively, in the realm of medicinal mushrooms. Anecdotal reports suggesUhis mushroom improves liver and kidney function and helps gastrointesti-^TlZTZTofLz to Singer (19« N the sclerotia of a related, tropical species, Pleurotus rooms indoors^. Symptoms include fever, headache, congestion, coughing, sneezing nausea & general malaise Workers who, at first, can tolerate contact with Oyster spores, often develop increased ™ nsitivity with contin ed exposure. Filtration masks help but do not entirely solve this work^place related problem. Tire question as to whether or not spores of Oyster mushrooms can cany mushrooms after they have been cooked. For more information, consult Reshef et al. (1988).

Flavor, Preparation & Cooking: Stir-fry in a light oil at high heat until golden brown and then cooked with other condiments.

Comments- Hie Oyster mushrooms are the easiest to grow Disadvantages of the' cultivation are in STstetf life post harvest and the h dth problems posed by the prolific spore load generated

TbedtTrm tures for initiating P. ostreatus ; based on cold weather strains. Strains evolving in warm geographical riches behave mo, in accordance with the parameters outlined for Pleurotus

PU1PZTo^^

er^t and responsive to carbon dioxide level, Zadrazil (1974) noted 80,000 ppm or 28% C02. Unless C02 levels are reduced to less than 1000 ppm (.0, %), noticeable

* For information on the cultivation of Pleurotus tuber-regium, consult Okhuoya et al. (1988 & 1990) and Omoanghe (1992). See Figure 43.

Spawn Run:

Temperature: 75°F.(24° C.) Relative Humidity: 85-95% Duration: 12-21 days C02:5000-20,000 ppm Fresh Air Exchanges: 1 per hour Light Requirements: n/a

I'rimordia Formation:

Relative Humidity: 95-100%

Duration: 3-5 days

C02:< 1000 ppm

Fresh Air Exchanges: 4-8 per hour

Light Requirements: 1000-1500 (2000) lux.*

Fruitbody Development

Relative Humidity: 85-90%

Duration: 4-7 days

C02:< 1000 ppm

Fresh Air Exchanges:4-8 per hour.

Light Requirements: 1000-1500 (2000) lux.

Cropping Cycle:

3-4 crops, 7-14 days apart, over 45-55 days.

malformations of the fruitbodies occur: typically long stems and small caps. In fact, the cap-to-stem ratio is an accurate measurement of atmospheric carbon dioxide levels in the growing room and is used as a visual cue by Oyster cultivators for increasing air exchange. This mushroom species is also super-sensitive to light levels. (See Eger (1980)). In low light, a

* Egeret al. (1974) determined that P. ostreatus forms the most primordiain response to a light intensity of 2000 lux or about 185 foot candles. Light intensities exceeding 2000 lux/hour caused a precipitous drop in the number of primor-dia forming. At 10,000 lux/hr. (>925 foot candles), primordia failed to form. Their studies showed that continuous, optimal light stimulation during the primordia formation resulted in the largest population of primordia. (However, I note that if the base nutrition or the strain can not support the development of such large population of primordia, the cultivator may actually reduce yield efficiency.) Studies by Kalberer (1974) showed that total yield was maximized (and stem mass minimized) at 300-430 lux at 12 hours per day. The critical primordia formation period extends for 6-7 days. If the total light exposure, measured in "lux hours" per day fails to exceed 2400, equivalent to 100 ux or approx. 9 ft. candles of continuous lighting, P. ostreatus is triggered into "coral" formation. (See Figure 190). Continuous lighting at optimal levels prevent re-vegetation of developing primordia, a phenomenon occurring with many strains grown in under-exposed settings. Once primordia are well formed, diumal cycles are recommended. As insightful as this research is, strain sensitivity could sway light optima in either direction.

similar effect to that seen under elevated carbon dioxide conditions is induced. When exposed to high light levels, pigmentation of the cap is usually enhanced. Blue strains become blue :. Brown capped strains become a richer brown. Similar results are also seen at lower end temperatures given constant llgThoradand Barron (1984) first noted that P. ostreatus exudes a metabolite toxic to nematodes. As the nematode lies stunned, the mycelium soon invades through one of its orifices, quickly consuming the internal organs. From an evolutionary viewpoint, this is remarkable that a saprophytic mushroom can »ecome predatory to an animal in its quest for new sources of nitrogen. This may well explain why nematodes have never been reported as a pathogen in Oyster mushroom cultivation whereas their occurrence in the cultivation of the Button mushroom {Agaricus brunnescens) is economically devastating and commonplace.

Plate 1. Fruiting culture of Agrocybe aegerita, the Black Poplar Mushroom.

Plate 2. Fruidng culture of Flammulina velutipes Enokitake. (Top right.)

Plate 3. Fruiting culture of Ganoderma lucidum Reishi or Ling Chi. (Middle left.)

Plate 4. Progressive development of the mycelium of Morchella angusticeps, the Black Morel.

Plate 1. Fruiting culture of Agrocybe aegerita, the Black Poplar Mushroom.

Plate 2. Fruidng culture of Flammulina velutipes Enokitake. (Top right.)

Plate 3. Fruiting culture of Ganoderma lucidum Reishi or Ling Chi. (Middle left.)

Plate 4. Progressive development of the mycelium of Morchella angusticeps, the Black Morel.

Pleurotus EunosmusPleurotus EunosmusMorchella Angusticeps

Plate 7. Flammulina velutipes, the Enoki Mushroom fruiting from bottles of supplemented sawdust.

Plate 8. Hypholoma sublateritium, Brick Tops or Kuritake. (Top right.)

Plate 9. Hypholoma sublateritium. Kuritake, fruiting from partially buned logs (Lower right.)

Plate 10. Hypsizygus ulmarius. the Elm Oyster Mushroom or Shirotamogitake.

Pleurotus Eunosmus

Plate 11 Azureus Stamets holding a 5 lb. supplemented sawdust producing a 1 lb sp :imen of Lent inula edodes, the Shiitake mushroom. (Left.)

Plates 12 & 13. Shiitake mushrooms fruiting from blocks of supplemented, alder sawdust. (Above and

Plates 17-20. Pleurotus citrinopilcatus, the Golden Oyster Mushroom, fruiting from columns of pasteurized wheat straw and from »ottles of sterilized sawdust.

Plate 21. Trays of harvested Golden Oyster Mushrooms ready for markei (Right.)

Plate 26. The type collection of M|*fc fflnofibrUlosa fruiting wildly from Douglas fir sawdust, ni ™,«r«Mt nnm. nrov. cultivated outdoors in hardwood chips.

Ladena StametsKreative Ideen Mit Gips

Plate 26. The type collection of M|*fc fflnofibrUlosa fruiting wildly from Douglas fir sawdust, ni ™,«r«Mt nnm. nrov. cultivated outdoors in hardwood chips.

Pleurotus Euosmus

Plate 28. Psilocyoe azurescens nom. prov. ready for harvest.

Plates 29 & 30. Sacrsd mushroom patches of Psilocybe cyanescens sensu lato, sometimes called Fantasi-takes cultivated outdoors

Plate 28. Psilocyoe azurescens nom. prov. ready for harvest.

Plates 29 & 30. Sacrsd mushroom patches of Psilocybe cyanescens sensu lato, sometimes called Fantasi-takes cultivated outdoors

Pleurotus Eunosmus

Plate 31. LaDena Stamets with 5 lb. specimens of Stropharia rugoso-annulata the King Stropharia or Garden Giant Mushroom.

Plate 32. Typicai fruiting.

Plate 33. Young buttons of King Stropharia fruiting from cased, pasteurized wheat straw.

Plate 34. LaDena Stamets with King Stropharia at ideal stage for consumption

Plate 35. 2 lb. specimen of King Stropharia.

Plate 32. Typicai fruiting.

Plate 33. Young buttons of King Stropharia fruiting from cased, pasteurized wheat straw.

Plate 34. LaDena Stamets with King Stropharia at ideal stage for consumption

Plate 35. 2 lb. specimen of King Stropharia.

Pleurotus EuosmusLadena Stamets

Plate 39. Hericium erinaceus Lion s Mane, fruiting from malt extract agar.

Plates 40 & 41. Classic Lion's Mane fruitbodies.

Plates 42 & 43. Auricularia polytricha, the Wood Ear or Kikurage fruiting from sterilized sawdust.

Plate 39. Hericium erinaceus Lion s Mane, fruiting from malt extract agar.

Plates 40 & 41. Classic Lion's Mane fruitbodies.

Plates 42 & 43. Auricularia polytricha, the Wood Ear or Kikurage fruiting from sterilized sawdust.

Images Stropharia ColoniesLath MartensitePleurotus Eunosmus
blocks of supplemented alder sawdust.
Very Detailed
Plate 50. Outdoor fruitings of Maitake arising from blocks buried into soil
Colonial Era Graveyard Marlboro New York
Plate 53. Wild fruitings of Maitake from a stately oak tree in a colonial graveyard in upstate New York.

Plate 54. Scanning Electron Micrograph (SEM.) of mushroom spore contaminated with bacteria. (Top left.)

Plate 55. S.EM, of mycelium with clamp connections. (Middle left.)

Plates 56 & 57. S.E.M. of emerging basidia. (Top right & lower left.)

Plate 58. S.E.M. of mature basidium about to eject spores. (Lower right.)

Pleurotos pulmonarias (Fries) Quelet

Pleurotus Eunosmus
Figure 286. Culture of P. pulmonarius 3 and 5 days after inoculation onto sterilized malt extract agar media

Introduction: According to studies recently published by Vilgalys et al. (1993), Pleurotus pulmonarius is ^rtually indistinguishable from P. ostreatus, and differs largely in its habitat preference for conifer woods, in the Western U"'ted States, P. pulmonarius is usually found at higher altitudes than P. ostreatus which prefers the lowland nver valleys P. pulmonarius and P. ostreatus grow on a variety of hardwoods, with P. pulmonarius primarily a spring mushroom and P. ostreatus growing most prevalently ; i the summer to fall. The North American collections, show a wider range .. color than the European collections. P. pulmonarius hosts a large complex of varieties, offering cultivators a rich resource for new strains. Most of these strains fruit in culture

Common Names: The Inc': an Oyster

The Phoenix Mushroom

Dhingri (in northern India)

"Pleurotus sa^or-caju^mis-applied by cultivators)

Taxonom. Synonyms & Considerations: This mushroom was first published as Agaricus pulmona'-'us Fr. in 1821. Similar to P. ostreatus (Jacq.:Fr.) Kummer andP. populinus Hilber & Miller, this species can be separated from them by a combination of habitat, macroscopic, and microscopic features. P. pulmona :us and P. populinus both share a preference for aspen and black poplar. P.

pubnonanus is usually more darkly pigmented and has spores generally notTonger than 10, long comoared to the paler P. populinus whose spores often measure up to 15, in length.

Cuklvator-mycologists have mistakenly called a vanety of this mushroom "Pleurotus sajorcm The true Pleurotus sajor-caju (Fr.) Singer has been returned to the ^^^^ ^^ ^

and is now called Lentinus sajor-caju (Fr.) Fries. Pleurotus sajor-caju ( S&h a^nrt^g oersis nt ring on the stem, and mmitic or dimitic hyphae composing the flesh. (P pulmonanusis monomit^c ) I^i light of this new information, Singer's remark in TheAgaricalesin Modem Taxoiwiny ST 78) concerning the similarity of P. sajor-caju and the likelihood of its sharing synonymy ^fallntbws dactybophorus and Le mushroom completely different than the one cultivators grow in United States and Europe and have n^t^sc^or-cc^u"has been mis-applied so frequently that confi ion will Hkely reignfor a considerable time Many of the scientific papers publish ed on the extraordinary yields of P. sajor-cayM on straw cotton wLtes, coffee residues (ad infinitum) are undoubtedly referring toasra.nofR plnonanus. See Hilber (1989), p. 246). Since the name has become namine a new variety, i.e. Pleurotus pulmonarius var. sajor-caju seems like a good compromise. Un til^hen, cdtivalors Should refrain from cal :ng this commercially cultivated Oyster mushroom

"Pleurotus sajor-caju", as it is incorrect.

Description: Cap convex at first, expanding to broadly convex, eventually flat or upturned and often wavy i n age 5 20 cm (+) in diameter. Grayish white to beige to Mac grey to grey-brown sometime with ptikfsh or orangish tones. (At high temperatures, the cap is lighter in ^^^argin conditions under cold conditions, the cap becomes very dark gray to grayish black.) Cap ma smooth to undulating like an Oyster. Color vanes according to the strain, lighting, and temperature con^ns Stems are ty ically eccentrically attached to the cap. Veil absent. Flesh generally fan. Strains of this mushroom rarely form clusters of more than 5 or 6 mushrooms.

Distribution: Widely reported from North America and Europe.

Natural Habitat: In the eastern United States, this mushroom primarily decompose hardwoods while in e western regions, the species can b , found at nuddle elevations (1200-3000 meters) on conifers {Abies and Picea). Common in the spring and summer.

Microscopic Features: Spores white to yellowish to lavender grey when dense, more or less cylindrical 7 5-11x3-4, Clamp connections present. Hyphal system monomitic.

Available Strains: Plentiful, available from most all culture

;llei "Pleurotus sajor-cajuA nearly sporeless strain, known as 3300 INRA-Somyce pro. uces about l/100th of the spore load of normal strains, but is less productive. (See Imbernon & Houdeau, 1991). The development for high yieldi g. low sporOJatmg strains of Pleurotus is essential to limit the impact spores have on the health of workers.

Mycelial Characteristics: White, linear, becoming cottony, and eventually forming a thick, peel-able, mycelial mat. If cultures on agar media or on grain are not transferred in a timely fashion (i.e.

Figure 287. P. pulmonarius fruiting from jar of sterilized sawdust

within two weeks), the mycelium becomes so dense as to make inoculations cumbersome and messy. Over-incubated cultures can not be cut, even with the sharpest, surgical grade scalpel, but aretorn from the surface of the agar media

Fragrance Signature: Grain spawn sweet, pleasant, and distinctly "Oyster-esque".

Natural Method of Cultivation: When the first log with fruiting Oyster mushrooms was brought from the forest into the camp of humans, probably during the paleolithic epoch, Oyster mushroom cultivation began. This mushroom is exceedingly easy to cultivate and il especially aggressive on alder, cottonwood, poplar, oak, maple, elm, aspen and some conifers. Other materials used for natural culture include wheat, rice or cotton straw, com cobs and sugar cane bagasse.

Since this mushroom grows wildly on conifers (Abies (firs) & Picea (spruce)), cultivators would be wise to develop strains that could help recycle the millions of acres of stumps that characterize the western forests of North America, il not the world.

Recommended Courses for Expansion of Mycelial Mass to Achieve Fruiting: Liquid inoculated gra ■ spawn sown dñectly into pasteurized straw or sterilized sawdust. This mushroom is more economically grown on pasteurized substrates, especially the cereal straws, than on wood-based substrates

Suggested Agar Culture Media: MYPA PDYA. OMYA and/or DFA. 1st, 2nd & 3rd Generation Spawn Media: Grain spawn throughout.

Figure 288. P. pulmonarius fruiting from 25 lb. bag of wheat straw

Substrates for Fruiting: Broadly adaptive, producing mushrooms on a great array of organic debris. The substrate materials proven to result in the greatest yields are the cereal (wheat, rice) straws, hardwood sawdusts, corn stalks, sugar cane bagasse., coffee waste (Martinez et al„ 1985), pulp mill sludge (1.dueller & Gawley, 1983), cotton waste and numerous other agricultural and forest waste by-products. Royse & Bahler (1988) found that the addition of 20% alfalfa hay to wheat straw increased yields substantially. In their studies, yields peeked when a comb: lation of wheat straw, aifalfa, and delayed release nutrients were employed. (The effect of delayed release nutrients on Oyster mushroom yield 's c i cussed in detail by Royse & Schisler, 1987a, 1987b.) Alfalfa hay, as any compost lakei knows, is considered "hot" because of its e1 evated nitrogen component. Although yields

, the li elih od of competitor molds increases directly as nitrogen levels are elevated.) For more information, consult ZadrazJ (1980).

Recommended Containers for Fruiting: Perforated plastic bags, columns, bags, trays, vertical racks, and bottles.

Field Potentials: Biological efficiency 100-200%, greatly affected by the size of the fruitbody at the t ae of harvest and whether or not a fourth or fifth flush is achieved.

Harvest Hints: Because this mushroom grows so quickly, the timing of harvest is critical to the quality of theoverall -op .shrooms more often form individually, in twos or threes, but rarely mo e^ Ne Mushrooms oftei form where the old mushrooms have been cut, a trait not generally seen w h Xrtorotuspecies.If mu .roomsar picked at full maturity, they are quick to rot, especially if kepfwithdn a container where gas exchange is limited Inder lese conditions, bacteria proliferate.

id hundreds of primordia form directly on the rotting fruitbodies. See Figure Form of Product Sold to Market: Mostly fresh. Some products, especially soup mixes, feature dried, powdered mushrooms.

Nutritional Content: Crude Protein (N x 4.38): 14-27%; fat:2%;

carbohydrates' 51% (on a dry weight basis). The variation in the reported protein composition of P. ^Ztan its close relatives is liscusse, 1 yRaietll (1988). ?or additional information on the

Was this article helpful?

0 0
Organic Gardeners Composting

Organic Gardeners Composting

Have you always wanted to grow your own vegetables but didn't know what to do? Here are the best tips on how to become a true and envied organic gardner.

Get My Free Ebook


Post a comment