Causes of Mushroom Death During the Cultivation of Agaricus blazei and Their Prevention and Control

Agaricus blazei Murrill, also known as the Brazil mushroom, has seen rapid growth in artificial cultivation over the past 2 years. In the cultivation of Agaricus blazei, the phenomena of small mushrooms shrinking, turning yellow, and finally dying occur, and their causes are mainly the following. By addressing these causes and promptly taking countermeasures, relatively large losses can be avoided.

1 Excessive temperature

When the mushroom shed is above 30°C for several consecutive days, combined with poor ventilation, mushroom death is likely to occur. Prevention and control methods: During the fruiting period, closely monitor temperature changes, regulate the shed temperature according to the temperature, ventilate and exchange air in a timely manner, and strictly prevent high temperatures inside the shed.

2 Poor ventilation

Poor ventilation inside the mushroom shed, insufficient oxygen, and excessively high carbon dioxide concentration can easily suffocate mushroom buds to death; if high temperature then occurs, mushroom death becomes even more serious. Prevention and control methods: In accordance with weather changes, pay attention to ventilation and air exchange, 2 to 3 times per day, and strengthen ventilation when the temperature is high. When ventilating, be careful not to let a large volume of air blow directly onto the mushroom buds.

3 Improper watering

The casing soil layer is not replenished with water in a timely manner (spraying fruiting water); during fruiting, the water sprayed is too cold, or too much water is sprayed during replenishment and moisture retention; in addition, spraying too much water at high temperature, shed humidity reaching above 95%, and poor aeration all easily cause mushroom buds to die. Prevention and control methods: For spraying water to increase humidity, persist in spraying little and frequently, prevent excessive spraying, and strictly prevent water from seeping into the substrate. Water spraying should be combined with temperature regulation and air exchange.

4 Overcrowded fruiting

A substrate that is too thin or on the dry side, casing soil that is too thin, and inadequate water management after the mycelium grows out and is covered with soil all easily lead to abnormal fruiting, weak mycelial vitality, and overcrowded fruiting.

5 Fruiting position too high

Too little casing soil combined with high temperature can cause overcrowded fruiting; when the casing soil is too thin, primordia grow out of the soil surface before they mature, and if fruiting water is not sprayed in a timely manner after casing, the mycelium emerges upward, raising the fruiting position, which can also cause some mushroom death. Prevention and control methods: After casing, temperature should be regulated and suitable humidity maintained in the soil layer.

6 Nutritional imbalance

Simply increasing the nitrogen source or replacing manure with straw material causes the carbon-to-nitrogen ratio to lose balance, resulting in mushroom death; reducing the amount of substrate used leads to insufficient nutrition in the later fruiting stage and causes mushroom death; compost that is over-mature or kept for too long causes insufficient nutrition, or compost that has not been composted long enough does not reach sufficient material temperature, so the nutrients are not fully decomposed and transformed, either of which can cause nutritional imbalance and mushroom death. Prevention and control methods: Prepare the substrate strictly according to the formula requirements, maintain a suitable carbon-to-nitrogen ratio, and carry out composting and fermentation as required.

7 Mycelial aging

Excessive generations of subculturing the mother culture, excessively high temperatures during spawn production, improper preservation, or excessively long preservation time can all cause mycelial aging, and after fruiting the mushrooms are prone to death. Prevention and control measures: Select excellent spawn, create suitable conditions for mycelial growth and development, strictly prevent high-temperature cultivation and preservation, and sow and use it in a timely manner.

8 Damage from diseases and pests

Damage from diseases and pests or improper pesticide use can both cause mushroom death. During fruiting cultivation, some diseases and pests inevitably occur; however, mistakes in using pesticides during disease and pest control can also lead to cultivation failure. During the fruiting period, the control of diseases and pests should use biological control or trapping methods as much as possible, so as to avoid pesticide residues and affect commodity quality. In preventing and controlling diseases and pests, adhere to the principle of prevention being more important than treatment and integrated control, and strive for early detection and early elimination.

9 Mechanical damage

Careless operation when picking mushrooms damages the surrounding young mushrooms, which is also one of the causes of mushroom death. Prevention and control measures: When harvesting, twist gently and pick gently, and try to avoid damaging the surrounding young mushrooms.

In short, after the causes are clearly analyzed, it is hoped that cultivating farmers can seriously learn the lessons, reasonably arrange the production season, carefully choose the cultivation method, reasonably select excellent cultivation materials, carefully select excellent spawn, carefully regulate the fruiting temperature, promote fruiting and primordium formation at the right time, improve management, control diseases and pests, and use pesticides reasonably, so as to achieve high quality and high yield.