Precautions for Topdressing Edible Mushrooms and Disease Control Methods

In the late stage of mushroom fruiting, in order to enhance the follow-up fruiting capacity, growers often add nutrient solution for topdressing. However, only when the correct method is used can the expected goal be achieved; otherwise, it will backfire and bring losses to producers. Attention must be paid to the application method. There are usually 3 methods for adding nutrient solution: spraying, soaking and hole irrigation.

1. Spraying method: The time for spraying nutrient solution is best when the fruiting bodies appear in large numbers. When spraying, care should be taken that the nozzle is not pointed directly at the fruiting bodies, and attention should also be paid to the "four no-spray" rules: first, do not spray on young small mushroom buds, so as to avoid their "swelling to death." Second, do not spray on places where mushrooms have just been picked or where mushroom remnants remain, so as to avoid causing bacterial diseases. Third, do not spray when air humidity is too high. Fourth, do not spray when pests and diseases are severe inside the mushroom shed (room).

2. Soaking method: It is mainly used for bag-cultivated edible mushrooms. After harvesting 1 to 2 flushes of mushrooms, if the cultivation bags are in a state of severe water shortage, they can be placed in a prepared nutrient solution to soak until they recover or approach their original weight. When using the soaking method to add nutrient solution, it is only necessary to place a heavy object on the fungus bags after they are immersed in the nutrient solution, but the soaking time should not be too long. If the fungus bags have lost too much water, they can be soaked several times in separate batches.

3. Hole irrigation method: It is mainly used on mushroom beds, and this method can be adopted when the mushroom bed produces many mushrooms and water and nutrients are consumed too much. The specific method is: punch holes in the mushroom bed at a hole spacing of 10 cm, flood the mushroom bed with the prepared nutrient solution, and cover with soil after adding the nutrient solution. The concentration must be appropriate. When the nutrient solution concentration is too high, not only is it difficult for the mycelium to absorb it, but it will also hinder and even damage the mycelium. When the concentration is too low, the effect is not obvious and the goal of high yield cannot be achieved. The concentration of the nutrient solution should also be determined according to the water content of the culture material. If the water content of the culture material is relatively high, the concentration of the nutrient solution should be increased, the amount of water used should be reduced, and after adding the nutrient solution, ventilation should be increased. Conversely, the concentration of the nutrient solution should be reduced and the amount of water used should be increased. The nutrients in the nutrient solution should be comprehensive. Several kinds of nutrient solutions should often be used alternately, so that the nutrients obtained by the fruiting bodies are both comprehensive and reasonable. If hormones are used to stimulate the growth of edible mushrooms, they should be used only after the nutrient solution has been supplemented. Attention should be paid to changes in the environment. When the temperature reaches 20°C or above, it is difficult for the mycelium to form high-quality fruiting bodies (except for high-temperature edible mushroom varieties), so nutrient solution may not be added. If the culture material has already been contaminated by miscellaneous fungi, the miscellaneous fungi must first be removed before adding the nutrient solution. In order to prevent contamination by miscellaneous fungi, a certain amount of bacteriostatic agent can also be added while adding the nutrient solution, so as to prevent the breeding and spread of miscellaneous fungi.