Eucalyptus wood in the processing process will produce a large number of residues such as bark, wood chips and sapwood, etc., the traditional treatment of these residues to the place of abandonment, incineration or landfill, etc., resulting in a huge waste of resources, but also serious pollution of the environment. Grass mushrooms belong to grass rot fungus, hyphae can decompose the cellulose and hemicellulose in the raw materials to make it a nutrient that can be absorbed and utilized, and the traditional grass mushroom cultivation raw materials are waste cotton and cottonseed husks. The use of eucalyptus bark instead of waste cotton or cottonseed shell cultivation of grass mushrooms new technology, the use of this technology not only for the eucalyptus processing residues of the resource utilization and enrichment of grass mushroom cultivation raw materials has great practical significance, but also can reduce production costs, reduce the occurrence of diseases and insect pests, improve quality and biological efficiency. Compared with other raw materials, eucalyptus bark has the advantages of large quantity, easy access and low price.
Eucalyptus bark as the main material cultivation of grass mushroom technology, through the addition of Bacillus subtilis, Gulebiform Bacillus and other microbial agents, promote the degradation of cellulose and hemicellulose in eucalyptus bark into simple sugars that can be directly absorbed and utilized by grass mushrooms, and at the same time make some harmful substances in eucalyptus bark volatilize. By mixing soybean flour evenly into the culture medium, the mushroom hyphae can absorb the nitrogen nutrients required for its growth as soon as possible, ensuring that the cultivation of grass mushrooms can obtain high yields. In addition, the use of secondary fermentation technology not only makes the culture material ripe in one step, but also kills the pests and harmful bacteria in the mushroom room and the culture material, which is conducive to the large-scale reproduction of beneficial microorganisms such as high-temperature actinomycetes, and is more conducive to the growth of grass mushrooms, which is easy to obtain high yields.
Discarded eucalyptus bark (network image)
1. Mushroom room facilities and sterilization treatment
The mushroom room can be surrounded by a layer of foam board, so that the mushroom room can be effectively controlled and adjusted according to the change of temperature, and the temperature required during the mushroom production period is ensured by installing air conditioning in the mushroom room or introducing hot steam from the outside. In addition, it is necessary to reasonably open convection doors and windows to ensure good ventilation performance. The mushroom room can optionally use a mushroom bed with a width of 1.2 meters, a length of 18 meters, a height of 6 layers, the first layer is 20 cm from the ground, each cultivation rack should not be too high, too wide, the layer spacing is 55 cm, each mushroom room can be placed in 2 to 3 columns of mushroom beds, that is, 1 bed frame on both sides of the entrance door and in the middle to facilitate daily mushroom management; the mushroom room should be strictly disinfected before use. That is, the floor and bed frame of the mushroom room are rinsed with clean water, and then disinfected with lime water or Bordeaux liquid with a concentration of 5% to 10%, or sprayed with 0.02% sodium hypochlorite solution for sterilization, and then disinfected with air disinfection products such as chlorine dioxide disinfectant in the mushroom room for 24 hours. After the harvest of the former stubble mushrooms is completed, the waste materials are cleared out of the mushroom room in time, and cleaned, and then disinfected with the above methods.
(Network illustration)
Second, the selection of cultivation seasons
According to the temperature requirements of grass mushrooms, the appropriate cultivation time can be selected according to local conditions. The optimal temperature for mycelium growth of grass mushrooms is 30~35°C; the optimal temperature for growth of fruiting bodies is 28~32°C. Guangxi is mainly cultivated from May to October, and it takes only 2 to 3 weeks from sowing to harvesting.
Third, the proportion of raw materials
There are three main types of raw material ratios.
1. Eucalyptus bark 50%, waste cotton 32%, rice bran 10%, soybean flour 8%.
2. Eucalyptus bark 50%, waste cotton 32%, wheat bran 10%, corn flour 8%.
3. Eucalyptus bark 42%, waste cotton 40%, rice bran 10%, soybean flour 8%.
Fourth, raw material fermentation
1. First fermentation
The eucalyptus bark produced by eucalyptus wood processing is crushed into thin strips that grow 0.2 to 3.0 cm thick and 0.1 to 0.5 cm thick, and are naturally stacked for 2 months. According to the amount of eucalyptus bark and waste cotton, and then the weight of the raw material weight of 0.15% of the heating starter agent added to it, while the water content is adjusted to 60% ~ 65%, with lime powder to adjust the pH value to 9, build a pile fermentation for 3 to 5 days, during which when the stack temperature rises to about 60 ° C when the pile is overturned, the pile can volatilize some harmful substances in the raw materials. Then according to the formula to weigh other excipients, first add rice bran or wheat bran to eucalyptus bark and waste cotton and mix evenly, and then dilute soybean flour or corn flour with water, soybean flour or corn flour: water = 1:20, dilute evenly into the culture medium, and stir evenly. After adding excipients, the water content is re-adjusted to 60% to 65%, the pH value is adjusted to 9, and the fermentation continues for 3 days.
2. Secondary fermentation
The water content of the fermented raw materials is adjusted back to 70% to 75%, the pH value is adjusted to 9, the moisture and pH are adjusted and then moved into the mushroom room while hot, evenly spread on the bed frame and the raw materials are slightly shaken, and the thickness of each layer is 10 to 15 cm. After laying the material, the temperature of the mushroom room is heated to about 65 ° C, maintained for 4 to 8 hours, and then open the doors and windows when the natural cooling reaches 45 ° C.
5. Vaccination
After the end of the secondary fermentation, when the feed temperature drops to 38 ° C, the temperature is sown, the strain is broken into a finger-sized block, to avoid crushing and damaging the hyphae to affect its germination, the strain is evenly sown on the material surface, and the material surface is slightly compacted, the amount of seeds per square meter is 600 grams, and after inoculation, some misty water can be sprayed around the mushroom room to improve the relative humidity of the air in the mushroom room, and then the doors and windows are closed to ensure that the temperature and humidity of the mushroom room are relatively stable.
Sixth, mushroom management
After the 6th day after inoculation, open the doors and windows for ventilation every day, morning, middle and evening ventilation for half an hour, at this time the hyphae have grown full of material surface, about the 8th day began to appear on the surface of the rice grain size white spots, at this time spray out of the mushroom heavy water, spray out mushroom water the next day after the small white dots began to differentiate into the original base, after 3 days for the formation of the original base, remember not to spray water on the mushroom bed, otherwise it will lead to a large number of deaths of the original base, until most of the original base grows into the size of the thumb can be sprayed with some misty water in small quantities. During the mushroom production period, the temperature of the mushroom shed is maintained at 28 ~ 38 ° C, when the temperature is too high, it can be appropriate to spray some misty water around the mushroom room and open the doors and windows to cool down, and when the temperature is low, it is the opposite, that is, less spray water and less ventilation. The relative humidity of the air is maintained at 90% to 95%, and the light is 300 to 350 lux.
During this period, if there is a ghost umbrella or other bacteria on the surface of the material, 10% of the lime water can be used to drench the damaged part to prevent spread.
7. Harvesting
When the fruiting body of the grass mushroom is egg-shaped, and the texture begins to become soft, and the membrane has not yet ruptured, it is harvested in time. When harvesting, press one hand against the surface of the material, and gently twist the base of the mushroom body with the other hand to avoid touching the small mushroom buds next to it.
Author: Wang Canqin, associate researcher of Institute of Microbiology, Guangxi Academy of Agricultural Sciences
Source: Southern Science and Technology News Micro-report