Discussion on the main problems and causes of the cultivation of Pleurotus ostreatus

At present, the cultivation area of Pleurotus ostreatus in our city has exceeded 50 million packets, which is one of the main varieties of edible fungi in our city, and the cultivation prospect and benefit are good. The cultivation of Pleurotus ostreatus can be cultivated year-round through cold storage and low temperature treatment. However, due to season, variety, medium, temperature treatment and improper water control, it often causes the death of mushroom or mushroom bud. Through years of cultivation practice, we explored and summarized the above problems for reference.

1 Variety selection at present, the main varieties in our city are Xiuzhen mushroom series introduced by Luoyuan from Taiwan, such as Xiu 57, Xiuzhen mushroom No. 1, 2, 3 and so on. There are some differences in cultivation characteristics and product quality, so growers should introduce suitable varieties according to the needs of the market. Generally, it is better to choose varieties that are suitable for cold storage treatment of mushrooms, more solitary mushrooms, quick tide change and good quality. At present, it is found that some varieties degenerate after being introduced for many years, showing that the fruiting period is delayed, and the mushroom is uneven or even not after low temperature treatment. Therefore, small-scale trial planting must be carried out after introduction; otherwise, it will easily cause problems such as unmarketable products and even no mushrooms.

(2) the natural climate is generally used in the cultivation season, and the bag-making of Xiuzhen mushroom can be arranged in February-March or September-October. In these two production seasons, the temperature is easy to control, the humidity is not high, and the success rate of bag-making is high. The bag-making in February-March should pay attention to heat preservation, and the bag-making from September to October should pay attention to the cooling. At the same time, the mushroom production period can meet the suitable season for Xiuzhen mushroom cultivation. Because Xiuzhen mushroom is mainly harvested Pleurotus ostreatus, the growth stage of each tide mushroom fruiting body is very short, the nutrient consumption is relatively low, but the tide times are more, but the whole cultivation cycle is longer, up to 6-10 months. When cultivated in a large area, the bag can be made for 1 or 2 seasons in a year. However, when industrial cultivation, there are perfect facilities, such as mushroom room temperature control conditions, cultivation sites with cold storage and other facilities, it can be produced annually. Otherwise, the mushroom period should avoid the high temperature in summer. Otherwise, if the temperature is higher than 28 ℃, it is very easy to cause no mushroom.

(3) the medium of culture material formula generally maintains a certain C / N ratio (20 ∶ 1 to 30 ∶ 1), which can prevent mycelium from growing and produce mushroom earlier, and the suitable medium is not easy to shrink and form lateral mushrooms in the later stage of culture medium. It is better to add proper cottonseed shell to the culture medium. The following formula is for reference: ① sawdust 77%, wheat bran 20%, gypsum 1%, calcium carbonate 1%, sugar 1%; ② cotton seed shell 78%, wheat bran 20%, lime powder 1%, sugar 1%; ③ cotton seed shell 39%, sawdust 39%, wheat bran 20%, sugar 1%, lime 1%.

(4) the main problems in cultivation.

4.1 dead mushroom

4.1.1 there are many and dense fruiting bodies at the initial stage of symptoms, and then wither and yellow to death, or several or all of them die.

4.1.2 causes and prevention of ① moisture: a. The culture medium is short of water and there is no water supply. b. The relative humidity of the air is insufficient and the mushroom body loses water. c. Water accumulated on the surface of hyphae or mushrooms. d. The ventilation lost water too fast. e. If the water is sprayed too hard, the primordium is loose. Preventive measures: before making the bag, the water content of the culture medium should be adjusted to 60%-65%; during mushroom emergence, the air relative humidity should be adjusted to 90%-95%; the water should be sprayed lightly and the mist should be repeated many times to prevent the surface of the bag from accumulating water and the primordium from loosening; when the mushroom is ventilated, we should pay attention to prevent the hot or cold air from blowing the mushroom bud for a long time; when the primordium is just formed, try not to spray water. ② temperature: a. The temperature changes too much, resulting in the return of nutrients and the death of mushrooms. Preventive measures: after the mushroom is formed, the temperature difference should not be too large. Attention should be paid to excessive temperature changes caused by excessive ventilation. b. Continuous high temperature and muggy heat. There is no certain temperature difference, resulting in dead mushrooms or no mushrooms. Under normal conditions, the high temperature lasts more than 28 ℃, and it is difficult to produce mushrooms without low temperature treatment. Preventive measures: the bag must be treated at a low temperature, while the temperature difference should be widened, generally at 10-15 ℃; also pay attention to the ventilation and cooling of the mushroom room, generally not more than 28 ℃. ③ hypoxia: lack of ventilation and hypoxia; different sizes of mushroom rooms can easily lead to different ventilation, resulting in local hypoxia; too high planting density will also cause poor ventilation, high carbon dioxide concentration, easy to form long-stalked mushrooms or dead mushrooms, etc.; poor ventilation is also easy to cause dead mushrooms mildew, thus affecting the normal growth of mushrooms, or even dead mushrooms. Preventive measures: 100 square meters is suitable for a single mushroom room; wall cultivation should not be too high, generally not more than 2m; each layer of bacteria is separated by two bamboo sheets, and each layer is staggered. ④ nutrition: the nutrition of bacterial bag was insufficient in the later stage. It is easy to open the umbrella early, forming thin mushrooms, or even dead mushrooms. Preventive measures: add more cottonseed hull and wheat bran to the culture medium to enhance the stamina. ⑤ pollution: bacteria package surface contamination of miscellaneous bacteria, mainly caused by dead mushroom untreated or stagnant water. Cause no mushrooms to grow or die. Preventive measures: immediately deal with dead mushrooms, scratch bacteria immediately; after immersion treatment, the water should be poured clean.

4.2 uneven mushroom production

4.2.1 symptoms some mushrooms grow in the same batch of mushrooms, some do not grow mushrooms, or after immersion in water and temperature difference stimulation in the same batch, the growth is different.

4.2.2 causes and preventive measures ① mycelium is too thick, which affects the formation of primordium: it may be due to excessive humidity and good ventilation during postharvest culture, resulting in the rapid growth of hyphae and the formation of mycelium. Or cultivation-based nutrition C ∶ N disorder. Precautions: peel or scratch the skin (may prolong the mushroom period by nearly 1 tide), or dig holes or cut bags behind to produce mushrooms. Try not to spray water during sterilization. However, the surface layer of the bacterial package can not be made too dry, otherwise, it will reduce the mycelium vitality and affect the amount of primordium occurrence. Generally speaking, the content of wheat bran in the medium should not exceed 30%. ② water distribution is uneven: water absorption is not uniform in the process of soaking, resulting in different mushroom production. Precautions: when making bags, try to make holes in the middle, so that water absorption can be faster and more uniform. ③ nutrition distribution is uneven: the mixing time is not long enough, resulting in uneven nutrition distribution and uneven mushroom production. Preventive measures: the ingredients of the culture medium should be fresh and the ingredients should be fully mixed. ④ temperature difference stimulation is uneven: the bacterial bag is stacked too tightly in the cold storage, resulting in uneven middle and edge treatment, or low temperature treatment time is not long enough, resulting in uneven mushroom production. Preventive measures: in the process of low temperature treatment, the bacterial bag should not be accumulated too tight, and the low temperature treatment time can be extended appropriately.

4.3 Lateral mushroom appeared around the cultivation package.

The reason: this is because the culture material is not pressed, the gap between the wall materials is easy to appear, and the soft culture material is more obvious; when the mycelium is physiologically mature, there will be a larger gap after cooling, and the oxygen supply is relatively good at this time. Lateral mushrooms are easy to appear under the induction of low temperature and light conditions, or lateral mushrooms appear when the mycelia become soft in the later stage of cultivation.

Preventive measures: packing is important, mix materials evenly; add more cottonseed shells appropriately; choose bacteria bags that are not easy to deform.

4.4 clump mushrooms and solitary mushrooms are cut, there are more tufted mushrooms; there are more single mushrooms; different varieties of single clump mushrooms have different characteristics; the surface of mushroom is flat, and there are more single mushrooms; the culture medium with high N content is also easy to form tufted mushrooms. Generally, tufted mushrooms or solitary mushrooms can be controlled as needed.

4.5 No mushroom Xiuzhen mushroom can be cultivated annually by low temperature treatment in cold storage. However, in the natural season, it is not easy to produce mushrooms at high temperature in summer, and the low temperature treatment time is too short or the temperature difference is not enough. Variety degradation is also easy to cause no mushroom. The bacterial bag was contaminated by bacteria, which showed that the mycelium growth was normal in the initial stage, and the bacterial bag was soft in the later stage, resulting in no mushroom.

Preventive measures: control the temperature of mushroom room not more than 28 ℃, prolong the time of low temperature treatment, select suitable varieties, sterilize bacteria thoroughly, and inoculate under aseptic conditions.

4.6 harvest immediately, leaving no mushroom stalk, scratching mushroom noodles immediately; mushroom noodles without stagnant water. Otherwise, mold pollution is easy to occur.

Postharvest management: cool the mycelium for 10 to 15 days to re-accumulate the mycelium nutrition and restore the vitality. At the same time, appropriate water should be sprayed during the culture period to prevent the surface mycelium from being too dry and affect the vitality. Then soak in water-absorb water-low temperature treatment (6: 9 ℃, or temperature difference more than 10: 15 ℃, more than 24 hours)-pour water-enter the mushroom room to manage-harvest again.