1, Nutrition: Mushrooms are saprophytic fungi, and their growth and development depend entirely on the nutrients in the culture medium. The carbon sources that mushrooms can use are glucose, sucrose, maltose, starch, vitamins, hemicellulose and lignin. They must be decomposed into simple carbohydrates by other microorganisms and enzymes secreted by mushroom mycelium before they can be absorbed and utilized. The nitrogen sources that mushrooms can use are urea, ammonium salt, peptone, amino acids and so on. Mushroom growth also needs some mineral elements, such as phosphorus, potassium, calcium and trace elements, such as iron and molybdenum. Therefore, when preparing culture medium, besides manure, urea, ammonium sulfate, calcium superphosphate and other main raw materials, a certain proportion of gypsum and lime should be added to meet the needs of mushroom growth and development.
2. Temperature: The mycelium growth temperature is 5-33℃, and the optimum temperature is 23-25℃. Below 5℃, the mycelium grows slowly. Above 25℃, although it grows fast, it is slender and weak and easy to age. When the temperature exceeds 32℃, the mycelium is easy to decline or turn yellow and upside down, so that it stops growing.
The fruiting body can be formed at 7-22℃, and the optimum temperature is 15- 18℃. In this temperature range, the fruiting period only lasts about 3 months. In the range of 13- 18℃, the fruiting period can reach 6 months. The fruiting body formed at lower temperature is white, thick, round and mushroom-shaped, with thick meat and high yield. In the process of fruiting body formation, especially during the period from young buds to young mushrooms, the temperature can only be maintained at the original temperature and cannot be increased, otherwise a large number of Pleurotus ostreatus or a large number of mushroom buds will shrink and die. Because hyphae are essentially like interconnected "tubes", they intertwine with each other at low temperature to form mushroom buds, and nutrients are transported to the mushroom buds through the flow of protoplasm in hyphae cells for growth and development. If the temperature rises, especially at a high temperature for a long time, the mycelium transports the nutrients in the mushroom buds to the surrounding hyphae for the mycelium to spread and grow, resulting in a large number of mushroom buds dying. The optimum sporulation temperature is 65438 08-20℃. If it exceeds 27℃, it is a fairly mature fruiting body and will not produce spores. The optimum temperature for spore germination is 24-26℃. Too high or too low will prolong the germination time or not germinate.
3. Moisture and humidity: The water needed in the growth of mushrooms comes from the covering of culture materials and the relative humidity of the air in the cultivation place. In the growth stage of mushroom mycelium, the water content of the culture medium is required to be 60-65%. Less than 50% of hyphae grow slowly, and many villous hyphae are slender, which makes it difficult to form fruiting bodies; When the oxygen content in the culture medium is higher than 70%, the growth of mushroom mycelium will also be affected. The humidity of the overburden should be kept at about 18-20%. Excessive drying will affect the development of mycelium and young mushrooms and reduce the quality of mushrooms. During the fruiting period, the relative humidity of the air should be controlled between 85-90%. If it exceeds 95%, water droplets will remain on the bacterial cover for a long time, which is easy to produce various plaques; If it is less than 70%, the surface of the bottle cap will harden or even crack, which is easy to sag; If it is less than 50%, the small mushroom buds will wither and die, and the mushrooms will stop growing.
4. Air: Mushrooms are aerobic fungi, which need a lot of fresh air in both the mycelium growth stage and the fruiting body generation stage. The CO2 concentration during spawning period should be controlled between 0.034-0. 1%. If it exceeds 0. 1% in the fruiting period, the cap is small, the handle is slender, and the umbrella is easy to open; If the concentration of CO2 is higher than 0.5%, it will inhibit the differentiation of fruiting bodies, stop fruiting, and at the same time, the villous hyphae in the culture medium will grow vigorously on the surface covered with soil. Therefore, it is necessary to ventilate in time and provide sufficient fresh air.
5, lighting: mushroom growth does not need light, the whole process can be carried out in a completely dark environment. The fruiting bodies grown in dark environment are white in color, round in shape and good in quality. However, when the fruiting body is generated, it is best to stimulate it with scattered light. The light in the mushroom room should not be too bright at this time. If the light is too strong, the surface of the mushroom body is easy to dry and turn yellow, and the quality decreases.
6.PH value: Mushroom mycelium can grow at PH value of 5.8-8.0, and the most suitable PH value is about 7. Because the mycelium will produce carbonic acid and oxalic acid in the growth process, the accumulation of these organic acids in the culture medium and covering soil layer will gradually make the living environment of mycelium sour and the PH value decrease. Therefore, when sowing, the PH value of the culture material should be adjusted to 7.8-8.0; Adjusting the PH value of soil particles to about 8.0 is beneficial to the growth of mycelium and can inhibit the occurrence of mold.
The preparation method of Agaricus bisporus culture medium is introduced below.
Process: preparing materials → pre-wetting → building piles → turning piles → making beds → entering sheds → sowing → fruiting management → covering soil → fruiting management → harvesting.
(1) Formula of culture medium and requirements for various materials (calculated by 500m2)
1. Formula: 6000kg of wheat straw, 6000kg of dried cow dung, 80kg of urea, 50kg of ammonium bicarbonate, 200kg of calcium superphosphate 150kg of lime, 200kg of cake fertilizer and 6kg of Gymboree beneficial bacteria. Total 12680kg, every 25.4mkg.
2. Preparation of culture medium: (1) The wheat straw should be fresh, yellow and mildew-free, and dried in the sun. All moldy and rain-soaked straws can't be used. The purity of pulverized dry cow dung should be above 80%. If there is more soil, the amount of cow dung should be increased appropriately.
3. The ratio of manure to grass is generally 4:6 or 5:5, and cake fertilizer should be added when manure is less than grass.
In the preparation of culture materials, there are more manure and less grass, and the permeability of culture materials is poor; However, there is more grass and less manure, and the culture medium has good air permeability, but poor nutrients. Therefore, when composting, in addition to dung and grass, cake fertilizer and chemical fertilizer should be added to supplement nutrients and increase looseness.
(2) Treatment methods before composting.
1. Fermentation time: It takes 7- 15 days to ferment with straw and cow dung.
2. Prewetting the culture material: firstly, cut the straw into 2-3 cm long, soak it in 5% lime water for 4 hours and take it out.
3. Pre-stacking: the soaked wheat straw, cow dung, cake fertilizer, calcium superphosphate, gypsum and calcium carbonate are crushed and mixed evenly to prepare stacking.
(3) Stacking and overturning
1. Preparation before pile construction: Before pile construction, calcium superphosphate, urea, gypsum and calcium carbonate are crushed and evenly mixed, and then fully mixed with pre-wetted cow dung and cake fertilizer to make a mixture, and urea water is sprayed to keep the water content of the material at 60%-65%. The pile foundation is 2m wide and 1.5m long.
2, build a heap:
(1) After three days of pre-piling, the temperature rises to 65-80 degrees, and the pile is turned over for three days. (2) turning over the pile for the second time: turning over the outside pile inside, continuing to ferment for three days, keeping the temperature above 65-80 degrees for three days, and then turning over the pile for fermentation until all the materials are brown, odorless and earthy.
(four) the quality standard of compost fermentation before entering the shed
1, and the medium is brown.
2. Wheat straw is soft and elastic, and raw materials such as straw and cow dung are evenly mixed.
3. The water content of the material is 65%, and there is a watermark between the finger of the material and 1-2 drops of water.
4, PH7.5 or so.
5, no pests and bacteria, no abnormal smell such as fecal odor, sour taste, ammonia smell, etc. , with the unique fragrance of mushrooms.
At this point, the whole culture medium has been successfully configured.