Causes and Control Techniques of the "Cowhide Bag" Disease in Wood Ear Mushroom
The cowhide bag fungus in wood ear mushroom is a disease that appears very easily during the cultivation of wood ear mushroom. Especially during mycelial growth or harvesting, if brown, relatively hard patches are found on the surface of the spawn bag, it is generally this pathogen that has struck. In that case, the wood ear mushroom will fail to produce fruiting bodies and yields will drop, which is a heavy blow for growers. Let us take a look below at the causes of the cowhide bag pathogen in wood ear mushroom and its control techniques.
I. Causes of the cowhide bag pathogen in wood ear mushroom
1. The cowhide bag pathogen in wood ear mushroom often appears on soil, cottonseed hulls, wood chips or the bodies of insects. Therefore, when cultivating spawn bags, if the temperature inside the bag is not well controlled and is relatively high when the mycelium grows to the shoulder of the bag, this contaminating fungus will appear. This is because this contaminating fungus can withstand high temperatures; even if you treat it with high-temperature sterilization, it will not be killed.
2. Another cause of the cowhide bag contaminating fungus in wood ear mushroom may be poorly controlled light. This is because light has an inhibitory effect on the growth of wood ear mushroom. If the light is particularly strong during the spawn bag cultivation period, the mycelium will develop black spots of mycelium-free, gelatinized tissue. As time goes on, the spots will become more and more numerous, and especially at the positions where brown spots grow, wood ear mushroom fruiting bodies can no longer grow.
II. Control techniques for the cowhide bag pathogen in wood ear mushroom
1. Every production step needs to be strictly controlled
Because contaminating fungi can occur at any stage of wood ear mushroom growth, we must strictly follow every step of standardized wood ear mushroom production, especially sterilization work, inoculation work and regular disinfection work. Spawn that carries contaminating fungi must not be used for production either.
2. Pay attention to disinfecting hole-punching tools
The cowhide bag contaminating fungus in wood ear mushroom very likely arises from cross-infection after hole punching, because the hole-punching tools were not disinfected properly. After punching holes in a spawn bag infected with Fusarium solani f. sp. pisi, continuing to punch holes in other uninfected spawn bags causes cross-infection.
III. Differences between wood ear mushroom infected by the cowhide bag pathogen and infected by mites
1. Distinguishing by color
If wood ear mushroom is infected by the cowhide bag pathogen, the color of the spawn bag changes from yellow to dark brown, and it will not be infected by other contaminating fungi.
If wood ear mushroom is infected by mites, the color will only be yellow, and only when it fades to the color of wood chips is there a possibility of infection by other contaminating fungi.
2. Distinguishing by hardness
The places infected by the cowhide bag pathogen in wood ear mushroom will gradually become solid and relatively hard. The places infected by mites will gradually become soft and loose in the spawn bag; this point is very easy to distinguish.
3. Distinguishing by shape
If wood ear mushroom is infected by the cowhide bag fungus, it appears in sheet-like form, and the contaminating fungus grows radially from a point to a surface. If infected by mites, the growth is in multiple points and at multiple positions.