What are the shiitake mushroom cultivation methods? Analysis of the log cultivation technique

Common shiitake mushroom cultivation methods include log cultivation and substitute substrate cultivation. Substitute substrate cultivation is further divided into mycelial brick block cultivation, shiitake mushroom bag cultivation, shiitake mushroom soil-covering cultivation and many other methods. Next, let us take a look at thelog cultivation technique for shiitake mushrooms.

In many parts of our country, shiitake mushroom production mostly uses the log cultivation method, that is, after trees are felled and properly dried, pure cultured spawn is inoculated onto the logs so that the mycelium becomes established in the logs and grows and develops shiitake mushroom fruiting bodies.

The production steps for log cultivation of shiitake mushrooms are as follows:

1. Choosing the mushroom yard For log cultivation of shiitake mushrooms, a site can be selected near where the mushroom logs are felled. Generally, choose a sunny spot in the middle of a large mountain and close to a water source, or build a shade shed on open ground as the mushroom yard. A two-yard system is generally used, that is, separating the “spawn running yard” and the “fruiting yard”. The spawn running stage is long and management can be relaxed, so the site is chosen facing east and south; the northwest direction has insufficient sunlight and is prone to cold wind. The selection of the fruiting yard should, according to the biological characteristics of shiitake mushrooms, create environmental conditions suitable for their growth and development, and provide control measures for temperature, humidity, light and so on during the fruiting period.

2. Preparing logs The trees selected for log cultivation are preferably birch, poplar and willow. Pine, cypress and similar trees contain phenolic substances and give off a pungent odor, so they are usually not used. When selecting logs, generally choose wood with many burls, more bark cracks, solid wood, more sapwood, less heartwood, and thicker bark that does not easily fall off; this kind of tree stores nutrients well. The diameter should be about 10-15CM.

3. Inoculation The inoculation period should be earlier rather than later, because when inoculating earlier the temperature is low, contaminating microorganisms have weak vitality and do not easily invade the logs, and the mycelium grows in the logs for a longer time, which is conducive to fully decomposing the logs, absorbing nutrients, maturing earlier and fruiting earlier. The spawn logs used for inoculation must be fresh and vigorous, and the interior must already be fully colonized; sawdust spawn is required to be fresh, not aged, free of contaminating microorganisms, and of appropriate spawn age.

Commonly used tools for shiitake mushrooms:

(1) Hole-punching machine The tool is generally an electric drill or a hole puncher. The drill bit diameter is generally about 1.2-1.3CM. If the holes are small, inoculation is difficult, the amount of spawn sown is small, and growth is slow; if the holes are large, the bark is easily damaged and split. Use is laborious and efficiency is low.

(2) Sealing materials Bark, paraffin, gypsum, or yellow mud without organic matter can be used.

(3) Other tools Such as the support frame used when punching holes, bark-scraping knife, inoculation tweezers and so on. These tools should be soaked in advance in 0.1% potassium permanganate.

Before inoculation, the moisture content of the logs should first be measured. When the measured moisture content is about 50%, inoculation can begin. The inoculation steps are as follows: ① Punching holes: first use an electric drill to punch holes in the logs. Generally, the hole depth is more than 2CM, and it should at least go 1CM into the xylem. Punch holes in a quincunx pattern vertically and horizontally all over the logs, with a longitudinal row spacing of 7-9CM and a transverse row spacing of 5-7CM. ② Inoculation: after punching the holes, take a small piece of spawn and insert it into the hole. The amount loaded should not be too much; fill the hole as the limit. Never tamp it in with a wooden stick or similar object. ③ Sealing: after the spawn is loaded, immediately cover the hole with bark and tap it firmly with a hammer, so that the bark is preferably level with the log surface. In actual operation, another hole puncher with a slightly smaller diameter is often used to cut covers separately so that they are firmly attached. The hole covers should be neither protruding nor sunken: sunken ones easily accumulate water and rot, while protruding ones are easily knocked off, causing the spawn to dry out or be eaten by insects. To ensure the bark covers are firm, paraffin can also be used to seal the openings. The formula for the paraffin sealing material is: paraffin 75%, rosin 20%, lard 5%, heated and melted together; after it cools, use a writing brush to dip and apply it to the cover openings; after cooling it adheres firmly.

During inoculation, try to make hole punching, inoculation and sealing all continuous operations. After inoculating one hole, punch the next hole, so as to avoid the hole walls drying out or becoming contaminated and affecting spawn running. Then carry out spawn running and fruiting management.