I. Growth and living conditions of Lentinus edodes

Lentinus edodes is a kind of wood rot fungus, which was originally wild and domesticated by artificial cultivation. Its growth and living conditions include nutrition, moisture, temperature, air, light, PH value and so on.

1 nutrition

Nutrition is the material basis for the formation and development of fruiting body of Lentinus edodes. The growth of Lentinus edodes mainly depends on hypha secreting various enzymes, decomposing lignin, cellulose and hemicellulose, absorbing carbohydrates and nitrogen-containing compounds, and a small amount of inorganic salts and vitamins. Therefore, the nutrition for the growth of Lentinus edodes includes carbon source, nitrogen source, mineral elements and vitamins.

(1) Carbon source Carbon source is the main nutrient source for the growth and development of Lentinus edodes. The carbon sources for cultivating Lentinus edodes are: sugar, starch, cellulose, hemicellulose, lignin, etc. The sawdust and cottonseed hulls we use to cultivate Lentinus edodes provide carbon sources.

(2) Nitrogen source Nitrogen source is an indispensable nutrient for the synthesis of living substances such as protein and nucleic acid in cells. Mushroom mycelium can absorb and utilize some organic nitrogen, and can directly absorb small molecular nitrogen sources such as amino acids and urea. The wheat bran and rice bran we added mainly provide nitrogen sources.

The ratio of carbon source to nitrogen source (C/N) is an important nutritional index in the growth and development of Lentinus edodes, and it is better to keep the ratio of C/N at 25 ~ 40 ∶1in the vegetative growth stage of mycelium. In the reproductive growth stage, the optimum ratio of carbon to nitrogen is 63~73∶ 1, and too high nitrogen content will inhibit the differentiation of primordia.

(3) Mineral elements

The main mineral elements required by Lentinus edodes are phosphorus, sulfur, calcium, magnesium, potassium, etc., and the trace elements such as iron, copper, zinc, manganese, boron, cobalt and molybdenum are very small, but they are also necessary for the growth and development of Lentinus edodes.

(4) vitamins

Because Lentinus edodes mycelium can synthesize general vitamins, but it can't synthesize vitamin B 1, so it can only be absorbed and utilized from the culture medium.

In substitute cultivation, the nutrient composition of the culture medium should not only meet the needs of mycelium growth, but also meet the needs of fruiting body development in the later stage of cultivation.

2. Moisture

The requirement of water for mushroom growth includes two aspects: one is the water content in the culture medium; The second is the relative humidity of the air in the growing environment. The suitable water content for mycelium growth is 60% ~ 65%, 52% ~ 60% when fruiting, and the relative humidity of the air should not be lower than 85%. However, after the mushroom bud occurs, under the condition of low relative humidity of the air (such as 55% ~ 68%), as long as other conditions are suitable, the flower mushroom with better quality can grow.

3. Temperature

Lentinus edodes is a low-temperature and variable-temperature fruiting fungus. The "temperature" in the production of Lentinus edodes contains three meanings, namely, air temperature, fungus temperature and heap temperature. Air temperature refers to the natural indoor or outdoor temperature. Bacterial temperature refers to the temperature of mycelium activity in the culture medium; Heap temperature refers to the temperature of the small space in the heap when the rods are stacked.

(1) Effect of temperature on mycelium growth

The optimum temperature for the growth of Lentinus edodes mycelium is 5 ~ 32℃, and the optimum temperature is 24 ~ 27℃. At this optimum temperature, Lentinus edodes mycelium grows vigorously, and its color is white and thick. Generally speaking, Lentinus edodes mycelium is resistant to low temperature and not high temperature.

(2) Effect of temperature on primordium differentiation and fruiting body development.

The suitable temperature for differentiation of Lentinus edodes primordium is 8 ~ 21℃, and the optimum temperature for differentiation is10 ~15℃. The optimum temperature for differentiation varies greatly with different Lentinus edodes strains. The temperature for fruiting body development is 5 ~ 24℃, and the optimum temperature is15 ~ 20℃. In the same variety, when the temperature is low within the appropriate temperature range, the fruiting body develops slowly, and it is not easy to open the umbrella, and the quality is good. When the mycelium reaches physiological maturity, it suddenly meets the external low-temperature stimulation for a short time, resulting in temperature difference, which will slow down the growth of the mycelium, promote the centralized transportation of nutrients, and accumulate them into aggregation points, so as to resist the adverse external environment and force the "disc-shaped" tissue to kink, thus forming primordium, and make the fruiting body occur more and orderly.

4. Air

Lentinus edodes belongs to aerobic fungi. Fresh and sufficient air is one of the important environmental conditions to ensure the normal growth and development of Lentinus edodes. When the air is fresh and oxygen is sufficient, complete aerobic respiration can release a lot of energy and ensure the good growth of mycelium. If the air is not circulated and fresh, the growth and reproduction of mycelium and the development of fruiting body will be inhibited, and even lead to death. Under hypoxia, mycelium can temporarily maintain its life through glycolysis, but it needs a lot of nutrients, and mycelium is prone to aging and death.

5. Lighting

Lentinus edodes is a phototactic fungus, and diffuse light with suitable light intensity is a necessary environmental condition for Lentinus edodes to complete its normal life history. Mycelia can grow in complete darkness, but on the contrary, light will inhibit the growth of mycelium. After a long period of light, mycelium will produce brown biofilm, which will make primordium appear early, and the growth rate will slow down with the increase of light intensity. However, under dark conditions, only vegetative growth can be carried out, but fruiting bodies cannot be differentiated. Even if the fruiting body barely grows, the color is poor, the flesh is thin and the stalk is long, and there are many deformed mushrooms. The most suitable light intensity for fruiting body differentiation is 50~ 100 lux, which is only the necessary light intensity for primordial differentiation, but not the suitable light intensity for fruiting body development. At low temperature, stronger scattered light is beneficial to the formation of mushrooms with thick meat, short stalk and dark cover color.

6. pH value

The mycelium growth of Lentinus edodes needs acidic environment, and the pH value can be in the range of 3 ~ 7, with the most suitable pH value of 4.5 ~ 5.5. After the mycelium begins to grow, the pH value decreases due to the production of organic acids such as acetic acid, succinic acid and oxalic acid, so the optimum pH value for primordium formation and fruiting body development is 3.5 ~ 4.5. At least part of the organic acids accumulated during the mycelium growth can promote the fruiting body to occur better through acidified culture medium.

In production practice, these factors should be reasonably coordinated and controlled according to the different requirements of different growth and development stages, and the best growth environment should be created as far as possible to achieve the goal of high quality and high yield.

Second, the cultivation techniques of fresh mushrooms in greenhouse

1, variety selection and seasonal arrangement

Fresh mushrooms are generally cultivated in greenhouses with medium and early maturity varieties. At present, the main varieties used in production are: 939, Qingke 20, 868, etc. The cultivation time is generally from the middle and late July to the end of September, and the inoculation of medium-mature mushrooms should generally be completed before the end of August.

2. Selection of strains

Mushroom strains must be selected with high yield, high quality, strong stress resistance, and the dual characteristics of strong mycelium viability, no miscellaneous bacteria and no pests. The important indicators for identifying a strain are purity, shape, growth, color and uniformity.

(1) Purity: High-quality strains must be pure mycelium culture without any other miscellaneous bacteria.

(2) Growth: The growth of a strain includes the state and speed of mycelium growth. A fast and robust mycelium is regarded as an excellent strain, while a strain with sparse, uneven and slow mycelium growth is regarded as a bad strain.

(3) Color: Excellent Lentinus edodes strains are white in color.

(4) Uniformity: The uniformity of the strain depends on the purity of the strain and the uniformity of the culture medium.

3. Site environment

(1) spawning site

The fungus growing place requires low light, good ventilation, good temperature regulation and moisture discharge, and can be grown in idle houses and courtyards or in mushroom sheds, but the mushroom shed used for fungus growing requires good shade and rain protection; Large-scale production needs to build a special fungus shade shed.

(2) Mushroom growing place

The mushroom farm should be located in a place with sufficient light, good ventilation, near water source, good drainage and flat terrain. The mushroom shed is built in an east-west direction.

As a place for fresh mushroom cultivation, we should choose an area with good ecological environment that is not affected by pollution sources or the content of pollutants is limited within the allowable range, and its water, soil quality and air quality for mushroom production management must meet the corresponding standards.

5. Mushroom shed structure

The cultivation of fresh shiitake mushrooms in greenhouses is generally the rotation of mushrooms and rice. After the mushrooms are produced, the shading objects can be removed for planting rice and other crops. The mushroom greenhouses are generally divided into an inner shed and an outer shed. The outer shed is used for shading, rainproof and moisture preservation, and the inner shed is used for moisture preservation and heat preservation. The mushroom shed is generally 4-6 meters wide and the length should be less than 30 meters to facilitate ventilation. The structures are usually bamboo strips or wooden strips, and the shading objects are generally used with sunshade nets and straw curtains. It is used in greenhouses.

6, rod production and management procedures

(1) ingredients

① Formula of culture medium:

Conventional formula: sawdust 78%, wheat bran 20%, brown sugar 1%, gypsum 1%, water content 58 ~ 60%.

② raw material requirements: strictly control the quality of raw materials, and prevent the use of adulterated and shoddy raw materials, especially those containing harmful substances. Miscellaneous sawdust is required to be made of high-quality broad-leaved trees, with fineness below 5mm, fresh color, no mildew, no caking, no odor, no oil pollution, water content14% ~ 60%, pH value around 8.0, and total nitrogen content around 0.3. Wheat bran should be high quality, fresh and dry, without caking, mildew, moth-eaten and adulteration;

③ Mixing: to achieve "three uniformities", that is, raw materials and auxiliary materials are evenly mixed, wet and dry stirred, and the pH value is even. Mixing with half-baked materials has special requirements.

(2) bagging

After the preparation of culture materials, they should be put into fashion bags, and the time interval from mixing to bagging should not exceed 6 hours. The materials should be mixed on the same day, bagged and sterilized on the same day, and it is not allowed to pile up overnight. The wet materials in each bag are about 1.8 kg. The bag mouth should be cleaned and tied tightly.

(3) sterilization and cooling

Keep10 ~12 hours when the feed temperature reaches 98 ~100℃, and then cool it to normal temperature in a clean place before inoculation.

(4) Inoculation

Inoculation is the most critical step in the production of bacterial sticks. The whole inoculation process must be carried out strictly according to the requirements of aseptic operation, strictly and quickly, so as to reduce the pollution of miscellaneous bacteria. Inoculation can be completed in inoculation box, inoculation room or tent plastic shed, including disinfection, constructio n inoculation and bagging.

① Disinfection

Disinfectants mainly include 75% ~ 78% alcohol, aerosol disinfection box, etc. Aerosol disinfection box is used for space disinfection of inoculation room and inoculation box, and disinfection time is 20 ~ 30 minutes. Inoculation utensils, strain surface treatment, inoculation utensils and hands of vaccinators are mostly scrubbed and disinfected with 75% ~ 78% alcohol.

② constructio n inoculation and sealing (outer bag)

Inoculate each rod with 3 holes early and 5-6 holes later. The diameter of the inoculation hole is about1.5cm. constructio n should cooperate with inoculation, punch a hole and connect a hole with strains. Inoculation should be quick and capable, and the seeds should be inserted into the inoculation hole by hand. The seeds should be compacted tightly without leaving gaps, so that the strains can be slightly raised to accelerate the germination and sealing of hyphae and avoid the infection of miscellaneous bacteria. Attention should be paid to it.

(5), culture management

After inoculation, the fungus sticks should be moved to a culture place with proper temperature, ventilation and light-proof, and the work of turning over the pile and checking the fungus growth, piercing ventilation, temperature control, ventilation and cooling should be done well.

(1) pile, pile and fungus inspection.

Turning over the pile and adjusting the stacking mode of fungus sticks are important measures to adjust the temperature and improve the ventilation conditions. They should be stacked in the shape of a "well" or a triangle, and the stacking amount per square meter should not exceed 50 fungus sticks at high temperature. If pollution is found, it should be removed and treated in time.

② Puncture ventilation

If the medium-ripe Lentinus edodes is selected, it is generally necessary to carry out puncture ventilation twice during the cultivation process, and the early-maturing variety can carry out puncture ventilation once. The time and method of puncture ventilation: when the hyphae at the inoculation port grow to a diameter of 6-8 cm, the first puncture ventilation is carried out, and the puncture method is to use an iron nail or bamboo stick with a length of about 5 cm (1.5 inch) to puncture a hole within 2 cm of the mycelium growth end of each inoculation hole. The total number of piercing holes in the whole stalk is about 20. The second piercing is usually carried out 5-7 days after the mycelium is full of bags. A nail-rake-shaped piercing device is used to pierce holes, and 15 and * * * four rows can be pierced on the stalk at one time. Early-maturing varieties are only ventilated for the second piercing.

After 4-8 days of puncture ventilation, hyphae will grow vigorously, breathing will be significantly enhanced, and a lot of heat will be released, which will obviously increase the temperature of the pile and the room temperature. Therefore, it is necessary to disperse the pile in time after each puncture ventilation, and strengthen ventilation and heat dissipation to avoid burning the pile.

③ Ventilation and cooling.

During the incubation period, due to the respiration of hyphae, a great deal of heat will be released, and the stacking temperature of fungus sticks is generally 3 ~ 5℃ higher than that of room temperature, especially after each puncture ventilation. Therefore, with the increase of mycelium growth and the increase of outside temperature, we should pay great attention to ventilation and reduce the storage of mushroom wood in each incubation room. Generally, ventilation1~ 2 times a day is required, and the temperature is 25℃.

(7) color change

Color-changing is a normal physiological phenomenon for substitute cultivation of Lentinus edodes. When the hyphae are full of bags, they have a certain maturity. Under certain conditions of air, light, temperature and humidity, the aerial hyphae on the surface begin to turn upside down, secrete pigments, spit out yellow water, and the color turns from white to brown. Finally, a film with moisturizing, heat preservation, light protection and anti-microbial effects is formed. This process is called color-changing.

Medium-mature varieties, generally faster color change, should promote the color change of fungus sticks in the bag, early-maturing varieties should generally be forced to change color after unpacking.

7, mushroom management technology

(1) selection of bag removal period

For the standardized greenhouse cultivation of fresh Lentinus edodes, the suitable bagging period is generally when the highest temperature in the mushroom shed drops below 25℃, which is generally from the end of1October to the middle of1month, and can be advanced to1middle of October in high altitude areas.

(2) bag removal and color change

Bagging should be done in sunny morning or cloudy day, and the temperature difference in rainy days is small. After bagging, the mushroom wood is susceptible to rain and infected with miscellaneous bacteria. It is not advisable to take off the bag. When taking off the bag, gently cut the plastic bag with a sharp knife and peel it off. It should be noted that the bag should be scratched lightly, as long as the plastic bag is cut, and the mushroom skin must not be cut, otherwise it will easily cause mold pollution.

For early-maturing varieties, after bag removal, the film should be covered and kept moist for 3 days to promote the growth of aerial hyphae. Then, the aerial hyphae should be ventilated and dehumidified to make them lodging and turn into brown fungus skins.

(3) autumn mushroom management

According to the characteristics of autumn climate and the influence of greenhouse mushroom bed on light, temperature, humidity and air, autumn management should focus on temperature control, moisture preservation and mildew prevention.

In autumn, the temperature is high, the highest temperature is close to 30℃, sometimes the temperature in the shed is over 30℃, and the relative humidity of the air is low. We should prevent high temperature and moisture, and do a good job in color change management. After color change is completed, we should adopt the method of temperature difference stimulation to promote buds. The specific method is to close the shed film during the day, cover the bed with a small film in the shed to raise the temperature, and open the shed door in the evening to ventilate1. After mushroom buds are formed, it is necessary to maintain a relatively stable temperature and humidity and do a good job of ventilation. Specifically, water can be sprayed on mushroom wood 1 time in the morning or evening, and the shed film is opened for ventilation, and the film is covered after the free water of mushroom wood evaporates.

If the temperature exceeds 23℃, the shed door film can be lifted at one end of the greenhouse during the day to reduce the greenhouse temperature. In the evening, the shed door films at both ends are opened, and the mushroom wood is sprayed with water 1 time, and then ventilated for 30 minutes. After the free water on the surface of the mushroom wood evaporates, the film is covered, which not only reduces the temperature, ventilates, increases oxygen, but also maintains a high humidity. The amount of water sprayed depends on the water retention performance of the mushroom farm.

The first batch of mushrooms should be picked in time when they grow to 7-8 minutes. If the water content of the mushroom wood is high after picking the first tide mushroom, the film should be lifted and ventilated for 8-12 hours every day, so that the mycelium can rest for about 7 days to accumulate nutrients, and then the temperature difference and humidity difference are still widened. After 6-8 days, the second tide mushroom can occur. If the mushroom wood is light after picking the first tide mushroom (the original weight) The water content of mushroom wood can reach 58% ~ 62%, and the intuitive standard can be mastered until light yellow water drops gush out on the surface of mushroom wood. After 6 ~ 8 days of moisturizing management, the second tide mushroom will be formed.

The greenhouse mushroom bed has the advantages of rapid warming and good moisture retention, and the temperature is high in autumn, which is easy to cause green mold pollution in a high temperature and high humidity environment, leading to local mildew of mushroom wood. If the quantity is not large, it can be prevented by manual weeding combined with drugs. First, the moldy part can be cleaned with a knife or bamboo stick to expose the normal part of mushroom wood, leaving no moldy things, and then it can be scrubbed or smeared with 50% carbendazim 200 ~ 300 times, which is effective.

(4) Mushroom management

In winter, the temperature is low, the metabolic activity of mycelium is weak, the nutrient accumulation is slow, and the process of primordium differentiation and fruiting body formation is slow. In sunny days, the greenhouse temperature rises rapidly, and the effects of heat preservation and moisture retention are good. Another effective measure to improve the yield of mushroom is to choose a reasonable method to accelerate the bud formation, shorten the time of mushroom bud formation, increase the number of mushroom bud formation, and grow as many tide mushrooms as possible. Because of the low temperature and low metabolic intensity of mycelium, the conventional film mulching in the daytime and film lifting in the evening will widen the temperature difference.

The key to the management of mushroom production in winter is to try to increase the greenhouse temperature, and the following operation methods can be selected: (1) exchange the sunshade net with the greenhouse film inside and outside to make more sunlight penetrate into the greenhouse to increase the greenhouse temperature; (2) When the temperature is low, remove the sunshade net, move it into the greenhouse and directly cover it on the small arch membrane; ⑶ Close the sunshade net on sunny days to increase the light transmission and raise the temperature of the shed, and open the closed sunshade net at night to increase the heat preservation effect. In management, combine mushroom picking and ventilation once a day for 30 minutes at noon when the temperature is high. Before ventilation, spray water to keep the humidity in the shed, and cover the film after the water drops on the surface of the mushroom wood are dried.

(5) Spring mushroom management

In spring, the temperature rises gradually, the temperature difference is large, and there is a lot of rainfall. The key points of management are to control the humidity, do a good job of ventilation and mildew prevention, replenish water in time, grasp the tide management, strive for more mushrooms, and add appropriate nutrients in combination with water supplement in the later stage to improve the yield.

In the early stage, the temperature was not high, so the main task was to replenish water to the mushroom wood. After the winter mushroom was harvested, the mushroom wood should be replenished in time after 6-8 days of recuperation and rejuvenation to promote the occurrence of mushroom buds. After the mushroom was harvested, the position of the sunshade net should be restored to its original position in time, with ventilation of 1 time every day for 30 minutes, and the amount of water spray should be determined according to the weather conditions until harvesting. After harvesting, the mushroom should be cultivated in time to replenish water and accelerate the buds. In the later stage, the temperature is high and humidity is high, (2) spraying water outside the greenhouse to cool down; (3) Open the door membrane at one end of the shed to reduce the daytime shed temperature; (4) Spray water once in the morning and once in the evening, each time for 30 minutes, so as to achieve the functions of cooling, increasing oxygen and keeping moisture. After harvesting, open the plastic film doors at both ends to cultivate bacteria for 6-8 days, and add 0. 1% urea and 0.3% calcium superphosphate, triacontanol10.5 ppm or 0.2% potassium dihydrogen phosphate into the make-up water.

8, pest control:

Environmental sanitation: the mushroom should be kept clean and ventilated.

② Trichoderma control: high temperature and high humidity should be prevented during mycelium culture, color change and fruiting, so as to create a ventilated and dry ecological environment. In non-fruiting, the high-efficiency and low-toxicity pesticide Tobuzin should be used for control, with the concentration of1:500.

③ Streptomyces: The temperature of the culture site is 23-25℃ and the relative humidity of the air is 60-70%. Isolate the infection in time, wrap it in wet newspaper and take it out for landfill treatment.

④ Comprehensive prevention and control of rotten tubes: choose the place where the highest temperature in summer does not exceed 30℃ as the most suitable cultivation place; It shall have a culture place for fungus segments corresponding to the number of cultivation, and be equipped with ventilation equipment. Yellow water shall be drained in time to prevent the rotten tube from being caused by accumulated water.

⑤ Pest control: the cultivation field is isolated with plastic nets to prevent mosquitoes and flies from entering; Stick a cloth with pesticides in the space of the cultivation field to drive them away, and do not spray pesticides directly on the mushroom body. The use of pesticides shall be carried out according to GB4285.