Key Production Technology Points for Flat-Bed Cultivation and Successive-Generation Cultivation of the Elm Oyster Mushroom (Pleurotus citrinopileatus)
The elm oyster mushroom (Pleurotus citrinopileatus), due to its strong growth vigor, good stress resistance, ease of cultivation and promotion, and high biological efficiency, has very broad development prospects in Shandong Province. Shandong Province is a major cotton-growing province, and in recent years the cotton planting area has risen sharply, with cottonseed hulls being of high quality and low price. The following is an introduction to the production technology for cultivating the elm oyster mushroom using cottonseed hulls as the main substrate, employing fermented substrate flat-bed cultivation and successive-generation cultivation.
I. Spawn Production
1. Spawn Selection Select strains with strong growth vigor, good stress resistance, high and stable yields, and a broad temperature adaptation range, such as Yuhuang-1 and Yuhuang-2. The mycelial growth temperature is 5-35 degrees, with 20-30 degrees being suitable; the fruiting body differentiation and growth temperature is 10-30 degrees, with the optimum temperature being 8-25 degrees. It is tolerant to carbon dioxide. Under conventional cultivation, the biological yield can reach 150%, and under successive-generation cultivation, the conversion rate can reach 200%. It is an excellent strain suitable for cultivation in Shandong Province.
2. Spawn Preparation
(1) Mother spawn uses an enriched and modified PDA medium: potato (peeled, sliced, boiled for juice) 200 g, wheat bran 50 g, sucrose 20 g, peptone 28, potassium dihydrogen phosphate 3 g, magnesium sulfate 1.5 g, agar 20 g, water 1000 ml. The technical indicators required are: mycelium white and sturdy, abundant aerial mycelium, strong mycelial wall-climbing ability, cultured at a constant temperature of 25 degrees, with the time to fill the tube being less than 7 days. Every year, the mother spawn should be tissue-isolated from fruiting bodies with strong growth vigor and good quality, and after purification, rejuvenation, and fruiting tests, it is expanded for use as production mother spawn.
(2) Stock spawn and cultivation spawn: conventional media include grain medium and cottonseed hull medium. A. Grain medium: @#@245@#@ grains (or sorghum grains) 99%, gypsum 1%. First wash wheat grains (or sorghum grains) with clean water, soak in clean water for 12-24 hours (the soaking time depends on the air temperature), remove, boil for 20 minutes, boil until the wheat grains (sorghum grains) expand and soften, have no white core, and do not split their skins, remove, drain the water, evenly mix in gypsum powder, fill into 500 ml saline bottles or 750 ml wide-mouth bottles, plug with cotton plugs, sterilize at 121 degrees under high temperature and high pressure for 2-2.5 hours, cool and inoculate aseptically, culture at a constant temperature of 25 degrees after inoculation, and the mycelium fills the bottles within 20 days. B. Cottonseed hull medium: cottonseed hulls 90%, wheat bran 10% (or cottonseed hulls 94%, corn flour 5%, gypsum 1%, potassium dihydrogen phosphate 0.2%, magnesium sulfate 0.1%), substrate-to-water ratio 1:1.35. Use 15 cm-17 cm x 33 cm-35 cm polypropylene bags, sterilize under high pressure for 2.5-3.0 hours or under normal pressure for 12 hours, culture at a constant temperature of 25 degrees after aseptic inoculation, and the mycelium fills the bags in less than 28 days.
II. Cultivation Technology
1. Seasonal Arrangement According to the environmental temperature requirements of the elm oyster mushroom, cultivation can generally be arranged in spring and autumn. In spring, the temperature rises quickly and the fruiting period is short, so in Shandong Province, cultivation is generally mainly arranged in autumn. Activated mother spawn (July 1) - stock spawn preparation (July 10) - cultivation spawn preparation (August 5) - fruiting bag preparation (September 1) - fruiting cultivation (October 1) - fruiting and management (October 15 to December 10).
2. Raw Material Selection and Ingredient Treatment The elm oyster mushroom mycelium grows quickly and has strong contamination resistance. There are many raw materials suitable for its growth, such as cottonseed hulls, sawdust, wheat bran, corn cobs, and other agricultural by-product residues and various crop straws. There are many cultivation methods, including raw material, cooked material, semi-cooked material, and fermented material cultivation. Years of experiments have proven that using cottonseed hulls as the main substrate, carrying out fermentation treatment, and adopting flat-bed cultivation and successive-generation soil casing cultivation of the elm oyster mushroom has a simple process, reliable yield, and excellent product quality, and is a high-yield cultivation model worth promoting.
(1) Substrate formula: cottonseed hulls 86%, wheat bran 10%, lime 3%, potassium dihydrogen phosphate 0.5%, urea 0.5%, Gushusus 5 ml/50 kg, Gule 125 ml/50 kg, Enfei 5 ml/50 kg, substrate-to-water ratio 1:1.25-1.3.
(2) Pile fermentation: Select fresh cottonseed hulls from the current year, and spread the cottonseed hulls out to sun-dry for 2-3 days before fermentation for later use. Weigh the required main and auxiliary materials according to the formula, evenly sprinkle the wheat bran and lime powder onto the cottonseed hulls, put potassium dihydrogen phosphate, urea, and trace element additives into water, dissolve and stir evenly, splash into the substrate, stirring while splashing, then turn the material with an iron shovel, mix the material evenly with a mixer, and begin pile fermentation. If there is little material, it can be made into a round pile; if there is more material, it can be piled into a long strip pile with a bottom width of 1.2-1.5 m, a height of 0.8 m, and unlimited length. Use wooden sticks with a diameter of 3-5 cm to make holes in the pile every 0.5 m square, reaching straight to the bottom of the pile. Cover the surface of the pile with woven bags or plastic film, and lift the film once every 4-6 hours for ventilation. When the material temperature rises to about 60 degrees, carry out the first turning. The turning should be careful and even, so that the low-temperature dry layer on the upper layer, the anaerobic fermentation layer on the lower layer, and the high-temperature fermentation layer in the middle exchange positions. If the bottommost layer turns black and smells bad, a small amount of quicklime powder can be added. Keep the material temperature stable above 55 degrees, turn the pile once every 36 hours, for a total of 3-4 turnings, about 7 days. When the last turning is completed, a large amount of white actinomycetes appears at the highest temperature spot in the material layer, the substrate is brown, and there is no sour, foul, or other off-odor, fermentation can be terminated, and the material should be spread out in batches to cool down. When the material temperature drops below 30 degrees, begin bagging and inoculation.
3. Bagging and Inoculation Select 43-45 cm x 26-28 cm x 0.0025 cm high-density low-pressure polyethylene plastic bags. Use a sewing machine needle to poke 3 rows of needle holes at both ends and the middle of the bag to facilitate ventilation and oxygen supply and speed up mycelial growth. When bagging, first tie one end of the plastic bag tightly with string, sprinkle in a handful of spawn blocks (spawn blocks from small jujube to egg size), fill in the fermented substrate, compact while filling, and when half-filled, sprinkle another layer of spawn, then continue filling the substrate, and when 6-7 cm from the bag opening, sprinkle another layer of spawn, level and compact, so that the spawn and substrate are in close contact, then tie the bag opening tightly with string. The key to inoculation is to inoculate more at both ends of the bag opening, with the inoculation amount accounting for 3/4 of the total spawn used, so that the elm oyster mushroom mycelium grows preferentially and occupies the substrate surface, inhibiting the breeding of foreign contaminants. The inoculation amount is 13-15% of the dry substrate weight.
4. Bag Arrangement for Mycelial Growth Choose a wind-sheltered, sunny, high, dry, and flat open-air shade net or under tree shade with convenient drainage and a clean surrounding environment, or choose a clean idle house as the mycelial growth room, and sprinkle a layer of lime powder on the ground to dehumidify and disinfect. (1) Bag arrangement: According to the air temperature at the time, determine the number of layers for arranging the bags. When the air temperature is above 20 degrees, arrange the bags in a single layer in a single row under tree shade or a shade net; when the air temperature is 15-18 degrees, arrange the bags in 1-3 layers in a single row; when the air temperature is about 10 degrees, arrange the bags in 3-4 layers in a single row; when the air temperature is 0-5 degrees, arrange the bags in 4-5 layers in double rows. Throughout the mycelial growth process, the bag temperature should always be controlled below 28 degrees. (2) Turning and sorting: Begin checking for contamination 5 days after inoculation, carry out the first turning after 7-8 days, and then turn once every 7 days thereafter. During each turning, check and remove contaminated bags, and handle them promptly.
5. Mushroom Bed Preparation and Filler Fermentation In the fruiting shed, dig mushroom beds running north-south with a depth of 20 cm and a width of 110-120 cm, leaving a 40-50 cm working path between beds. Sprinkle a small amount of quicklime powder in the beds, mix evenly with the topsoil, and water thoroughly.
Filler preparation: Cut various crop straws (corn stalks, soybean stalks, etc.) into 2-3 cm small segments, pre-wet them without adding any additives, mix only with 30% fertile soil, build a pile and ferment for 4-5 days, and reserve as filler for successive-generation soil casing cultivation.
6. Bag Removal and Bed Placement
(1) Flat-bed cultivation: Remove the outer film from the bags fully colonized by mycelium, arrange them in the beds at a spacing of 2-3 cm, and fill the middle and top with 2-3 cm of fertile soil. Soil casing preparation method: Take soil from below 10 cm of the surface layer of a vegetable garden, disinfect with 2% lime water or 0.1% carbendazim aqueous solution. The soil moisture should be such that it forms a ball when squeezed in the hand and breaks apart when dropped on the ground.
(2) Successive-generation soil casing cultivation: Remove the outer bags from the fruiting bags of the oyster mushroom after four stages of mycelial growth, place them upright in the beds at a spacing of 10 cm, and fill with fermented straw filler to increase the amount of mycelium and the nutrient absorption area of the mycelium, thereby achieving the goal of increasing yield and benefits. Research has shown that the cultivation characteristics of the elm oyster mushroom are similar to those of the common oyster mushroom, so successive-generation cultivation can also be adopted.
7. Fruiting Management After 5-6 days of casing, when the mycelium emerges from the soil and forms a continuous sheet, spray a heavy watering once, control the environmental temperature at 10-15 degrees, carry out low-temperature stimulation for 3-5 days, and at the same time provide an appropriate amount of scattered light. When light yellow elm oyster mushroom primordia form on the bed surface, raise the relative air humidity to 85-95%, with a temperature of 18-25 degrees, and pay attention to ventilation and insect prevention.
8. Harvesting and Later Management After the elm oyster mushroom primordia appear, under normal conditions they mature in 7-10 days. Harvest when the edge of the fruiting body cap shows a wavy shape and a small amount of spores are being discharged. Stop watering 1 day before harvesting. When harvesting, press the substrate surface with one hand, insert the other hand under the fruiting body and twist left and right to pick it off, or cut the fruiting body at the base of the stipe with a knife. After harvesting the fruiting bodies, stop watering for 2-3 days, remove mushroom roots and deformed mushrooms from the substrate surface, loosen the aged mycelium, and fill in new soil. If the substrate is short of water, make holes to supplement water. In the middle and late fruiting stages, supplementary nutrient solution can be added to the substrate along with water supplementation. Trace element fertilizers such as Gule, Gushusus, and amino acid multi-element micro-fertilizers can also be sprayed.
III. Pest and Disease Control The elm oyster mushroom has a relatively short cultivation history in Shandong and a relatively small promotion area. During the experimental and pilot testing periods, no infectious diseases were found, and the incidence of physiological diseases was also lower than that of conventional cultivated varieties such as the oyster mushroom. Therefore, we only investigated and controlled insect pests of the elm oyster mushroom.
The elm oyster mushroom has the characteristic of fruiting at high temperatures, and its color is bright yellow, making it relatively prone to insect pests. Through systematic multi-point surveys in mushroom houses, there are mainly four types of insect pests in elm oyster mushroom sheds, namely the eye gnat, the louse fly, the Pyemotes mite, and the gall midge. The eye gnat is the dominant species, accounting for 90% of the pest population.
The eye gnat, also known as the dark-winged fungus gnat, occurs commonly in Shandong. It has multiple generations per year in mushroom houses, with overlapping generations. The first adults appear in early March, and the peak of infestation is from late March to mid-June. Adults are active, mostly hiding during the day between bags or in dark places under mushroom bodies, and after being disturbed they fly a short distance and then hide again. They also often fly to wall corners, doors and windows, and are most active in the evening, with obvious phototaxis and mushroom-taxis (they like yellow). Adults have a short lifespan, generally about 3 d. After adults die, they mostly stick to the back or front of mushroom bodies, affecting commercial quality. Larvae like to live in groups in the substrate, move about and feed, and damage mycelium, primordia, and young mushrooms. Bags that fruit again in spring are severely damaged.
Control methods: The occurrence period of the eye gnat is often during the fruiting period. Chemical insecticides have good insecticidal effects, but are prone to causing phytotoxicity, so comprehensive
First, do a good job of mushroom shed sanitation and environmental sanitation to reduce insect sources.
Second, before early March, seal the mushroom shed doors and ventilation openings with fine gauze to reduce external insect sources.
Third, after mid-March, reduce the temperature in the greenhouse as much as possible, controlling the greenhouse temperature at 15-20 degrees.
Fourth, chemical control.
(1) Fumigation with 80% DDV stock solution: dip cotton in the stock solution (at a dosage of 0.5 ml per cubic meter), hang it at doors, windows, ventilation openings, and inside the shed for fumigation.
(2) Spray with low-concentration pyrethroid pesticides, but attention must be paid to a safety interval of 5-7 days.