In short, oyster mushroom mycelium eats the substrate.
That is, it uses nutrients from plant materials for the development of mycelium and the formation of fruiting bodies.
All this is necessary for reproduction by spores.
The mushroom grower's task is to pick the oyster mushrooms before the spores begin to form - this is good not only for health, but also for business.
These white threads in the photo are spores that have adhered to the filamentous secondary mycelium.
Oyster mushrooms feed in a very interesting way, through hyphae.
Hyphae are thin “webs” of mycelium with which it grows to obtain water and nutrition.
In the picture below you can see a fluff that radiates away from the center like needles.
In this center there is a grain, the hyphae begin their growth from it.
These filamentous processes grow at the apex. In biology, this tip is called apex, and growth, accordingly, is called apical.
Through the growth tip of these threads, the mycelium releases enzymes.
They are called "exo-enzymes" because they work on the outside of cells. They dissolve nutrients, converting them into a form that oyster mushrooms can absorb. And they suck this solution back into the cells, passing the nutrition, like a relay race, to other cells and increasing biomass.
So that it is suitable for the work of enzymes.
If the mass is not wet enough, the enzymes will not be able to process all the available nutrition.
And if it’s too wet, a whole range of problems will arise, leading to defective mushroom blocks:
Interestingly, the range of humidity from “low” to “excessive” is very small.
If you disinfect the substrate with chemicals (like lime) or hot water, the range of optimal humidity is generally tiny.
66% humidity is still not enough, but 70% may already be a lot. Sometimes blocks even with 71% humidity give good yield. But this is rather an exception to the rule.
For pasteurized substrates, even 72% is not the limit. If the raw materials are properly prepared, the substrate bears fruit well even at 73-74% humidity. But this is also not a standard situation.
And not all types of straw, husks and hay are capable of this. And not all pasteurization modes are designed for this.
In general, it’s better not to take risks, 71% is quite OK.
This, by the way, is the answer to the question: “After collecting the second flush, is it possible to steam this substrate and sow it with new grain spawn.”
It is forbidden!
Everything in this substrate has already been eaten and it is permeated through and through with mycelial hyphae. There is no room for new mycelium there. Would you really like it if 15 more people moved into your apartment? 😆
There seems to be enough space, but you live there alone (or two or three of you)…😉
In sterile technology, tunnel pasteurization and xerothermy, working with plant mixtures gives positive results.
Due to the fact that the addition of one or another component improves the structure of the substrate and enriches it with a variety of nutrients.
Of course, you need to understand why exactly you are adding this raw material. To increase/decrease density, moisture, hardness, wrinkleability, etc.
It happens that batches with sufficient nitrogen yield less yield than batches with modest nitrogen (0.65-0.7).
This is due to the fact that nitrogen is most fully absorbed only in the presence of sufficient amounts of phosphorus and potassium. Therefore, it is important to know not only the amount of nitrogen as such, but also their ratio.
But this does not mean that potassium or phosphorus fertilizers can be poured into the substrate. Oyster mushroom does not absorb substances from inorganic compounds!
Don't forget that mushrooms are not plants!
Yes, he will... Grow! But it will not bear fruit.
Mycelium takes over compost well, because there is a lot of half-eaten straw, from which it is easy to extract food.
But... that's where it all ends.
The mycelium grows very quickly at first, then it lacks nutrition.
After all, the straw along with it continues to be eaten by a whole army of microorganisms, which were specially grown for compost.
Champignons are saprophytes, that is, they feed on organic debris, so they have plenty of food there.
This photo shows that the mycelium has whitened the entire compost, but there is no dense growth. Often, after a while, bare spots of compost appear, as the oyster mushroom mycelium there dies off due to the activity of other organisms.
Oyster mushrooms generally very rarely appear in such experiments. And this happens on the 35-40th day.