Analysis of Selenium-Enriched Black Fungus Production Technology

Compared with conventional cultivation methods, selenium-enriched black fungus production technology can increase yields by 10%–20%, generating additional income of RMB 10,000–20,000 per 10,000 bags. The quality of the product is enhanced to meet selenium-enrichment standards (selenium content in black fungus fruit bodies ≥ 0.5 mg/kg), allowing a price increase that can generate an additional RMB 30,000 per 10,000 bags. Additionally, resistance is improved, reducing pesticide usage and saving approximately RMB 300 per 10,000 bags. With promising market prospects and significant economic benefits, this article summarizes key points of selenium-enriched black fungus production technology to guide and assist growers.

1. Cultivation Seasons: Spring Cultivation and Autumn Cultivation.

2. Selenium-Enriched Black Fungus Production Process
   (1) Substrate Selenium-Enrichment Process: Raw Material Processing → Mixing (Adding Exogenous Selenium) → Bagging → Sterilization → Cooling → Inoculation → Mycelial Cultivation → Bag Opening & Sprouting → Ear Growth Management → Harvesting & Drying.
   (2) Spraying Selenium-Enrichment Process: Raw Material Processing → Mixing → Bagging → Sterilization → Cooling → Inoculation → Mycelial Cultivation → Bag Opening & Sprouting → Ear Growth Management (Spraying Exogenous Selenium) → Harvesting & Drying.

3. Cultivation Techniques
   (1) Cultivation Materials: Choose fresh, unspoiled, pest-free raw materials for the cultivation substrate.
   (2) Reference Formulas: Formula 1: Sawdust 88%, Bran 11%, Gypsum 1%. Formula 2: Sawdust 86.5%, Bran (or Rice Husk) 10%, Soybean Meal 2%, Gypsum 1%, Lime 0.5%. Maintain moisture content at 55%–58%, and adjust pH to 6.5–7.0.
   (3) Raw Material Processing: Properly process the raw materials before use.
   (4) Mixing: Measure and mix all ingredients according to the formula. For selenium-enriched substrates, add exogenous selenium during mixing, maintaining a selenium content of 2–4 mg/kg (based on pure selenium).
   (5) Bagging and Sterilization: Atmospheric Sterilization: Maintain 100°C for 10–12 hours. High-Pressure Sterilization: Maintain 121°C–125°C for 2.5–3 hours.
   (6) Cooling and Inoculation: Inoculate when the bag temperature drops to 25°C–30°C.
   (7) Mycelial Cultivation: Incubate in darkness at 22°C–28°C, ensure ventilation, and regularly inspect for contamination.

4. Cultivation Management
   (1) Bag Opening: Use mechanical tools to open the bags.
   (2) Sprouting: Choose outdoor or indoor sprouting methods based on the cultivation model and season.
   (3) Ear Growth Management: For Substrate Selenium-Enrichment: Follow standard ear growth management, controlling relative humidity at 80%–90% and temperature at 15°C–28°C. For Spraying Selenium-Enrichment: Dilute 0.2–1.1 g of pure selenium in 30 liters of water, and evenly spray onto 4,000–5,000 bags. First Spray: When the first crop reaches 0.3–0.5 cm. Second Spray: When the first crop reaches 0.8–1.0 cm. Third Spray: When the second crop reaches 0.3–0.5 cm. Fourth Spray: When the second crop reaches 0.8–1.0 cm. Control relative humidity at 80%–90% and temperature at 15°C–28°C.

5. Harvesting and Subsequent Crop Management: Stop watering 2–3 days before harvesting, and prioritize harvesting larger ears while leaving smaller ones to grow. For sprayed selenium-enrichment, stop spraying selenium 10 days before harvest. Drying: Use natural sunlight or mechanical drying. Post-Harvest Management: Stop watering, dry the bags for 3–5 days to allow mycelium recovery, and then rehydrate the bags for the next crop.

6. Conclusion: The application of selenium-enriched black fungus production technology improves yield, quality, and resistance. The selenium-rich fruit bodies enhance the nutritional profile and value of black fungus, creating a new economic growth point for the industry. This method demonstrates significant economic and social benefits.