Pleurotus djamor

This species encompasses a complex of brilliantly pink Oyster mushrooms. The pink Oyster varieties are the most common occurring wild Pleurotus in pan-tropical climatic zones of the world. Known for its speed to fruiting, ability to flourish on a wide variety of base materials, and high temperature tolerance, this species is so aggressive as to colonize unpasteurized bulk substrates before competitors can flourish. When growing this mushroom en masse, albino clusters sometimes form.

Mycelial Characteristics: White at first, casting a longitudinally linear mycelium, often over-run with long, diverging rhizomorphs, eventually cottony with maturity, and aerial. Most strains soon develop strong pinkish tones, especially as the mycelium matures, at and around the sites of primordia formation. Flaming pink primordia often form as cluster colonies along the inside periphery of the petri dish and/or around the site of inoculation. As grain (rye) matures, pink rhizomorphs and mycelia can predominate. A milky gray metabolic exudate collects at the bottom of the incubation containers.

Microscopic Features: From the same fruiting pink spores are collected from pink mushrooms, and light beige spores from mushrooms that were originally pink but faded to cream beige.

Suggested Agar Culture Media: Malt Yeast Peptone Agar (MYPA), Potato Dextrose Yeast Agar (PDYA), Oatmeal Yeast Agar (OMYA), or Dog Food Agar (DFA)

Spawn Media: Grain spawn for all three generations.

Substrates for Fruiting: Hardwood sawdust, cereal straw, corn waste, coffee residue, cotton waste, banana fronds, palm debris, and sugar cane bagasse. One formula employed be Brazilian growers calls for the proportionate mixing of 100 lbs. sugar cane/ 8 lbs. rice bran/ 3 lbs. rice straw/ 2 lbs calcium carbonate. The mixture is mixed, wetted, and pasteurized at 140* F for 2-4 hours. Bano et al. found that this mushroom (as "P. flabellatus") gave the highest yields when cotton seed powder was added at 132 g. per kg. or dry wheat straw. The total mass of the mushrooms grown was 85% over the yields from unsupplemented wheat straw. Interestingly, the protein content of the dried mushrooms also rose to 38%.

Royse and Zaki found that the dual addition of the commercially available supplements Spawn Mate II and Fast Break at a combined rate of 168 g. per kg. of wheat straw substantially enhanced yields of "P. flabellatus". In these tests, biological efficiency increased from 22% to 77% in a 28 day harvest period. It is suspected that the yields of other Oyster species would be similarly improved.

Yield Potentials: Given good crop management, biological efficiency rated at 75-150%, largely dependent on the age of the fruibody at harvest. Some strains of this species are equally as productive, in terms of biological efficiency, as the most vigorous strains of P. pulmonarous and P. ostreatus.

---Growth Parameters---

Spawn Run:

• Incubation Temperature: 75-85* F (24-30* C)
• Relative Humidity: 95-100%
• Duration: 7-10 days CO2: >5000 ppm
• Fresh Air Exchanges: 0-1 per hour
• Light Requirements: n/a

Primordia Formation:

• Initiation Temperature: 65-75* F (18-25* C)
• Relative Humidity: 95-100%
• Duration: 2-4 days
• CO2: 500-1000 ppm
• Fresh Air Exchanges: 5-8 per hour
• Light Requirements: 750-1500 lux

Fruitbody Development:

• Temperature: 70-85* F (20-30* C)
• Relative Humidity: 85_90%
• Duration: 3-5 days
• CO2: 500-1500 ppm
• Fresh Air Exchanges: 5-8 per hour
• Light Requirements: 750-1500 lux

Cropping Cycle:

• 2 crops, 7-10 days apart

Comments: This complex of Pink Oyster Mushrooms hosts some of the fastest growing stains of mushrooms in the Genus Pleurotus. For those with limited access to pasteurization equipment, and living in a warm climate, strains of P. djamor uniquely fulfill a critical need. Its speed of colonization, short but productive fruiting cycle, and adaptability to diverse substrate materials, make this species affordable to many cultivators, especially those in developing countries.

Zadrazil noted that this mushroom (as :P fabellatus") and Stropharia rugoso-annulata proved to be the best at rendering straw, after fruiting, into a nutritious feed staple for ruminants, especially cattle.

(Information taken from Growing Gourmet and Medicinal Mushrooms, Paul Stamets)