Abnormal mushroom is a relatively common physiological disease in the production of Pleurotus ostreatus, which seriously affects the yield and quality of Pleurotus ostreatus and even completely loses the value of the commodity. This disease is mainly caused by improper management, and a few are caused by strain degradation, mutation, and virus infection. The main types of malformed mushrooms are: 1) The high-yield mushroom has a small cover, poor differentiation, and a long handle. The reason for this is the formation and differentiation of the primordium, the lack of oxygen in the mushroom house, lack of light, and the high temperature, which affects the normal differentiation and development of the cap. Control methods: Strengthen ventilation, adjust light and temperature. 2. The appearance of tumor cap mushroom cap, mainly with many granular protrusions on the edge, light color, mushroom cap stiffness, growth retardation, severe mushroom cap differentiation is poor, irregular shape, because the mushroom body development temperature is too low, continued A longer period of time causes the growth of cells in the inner and outer layers to be disordered. Control methods: Adjust the mushroom house temperature above the minimum temperature of Pleurotus ostreatus growth, and there is a certain temperature difference, promote mushroom growth, development, differentiation. 3, cauliflower mushroom image cauliflower, more branches, the initial primordium were egg-shaped, swelling, uplift, no differentiation. There are more branches in the later period. The reason is that the mushroom bed or mushroom house is sprayed with a high concentration of pesticides before the mushrooming or during the mushrooming period, especially the “dichlorvosâ€. The juvenile mushroom is extremely sensitive to this disease most easily. It may also be that the mushroom house contains other harmful gases such as excessively high carbon dioxide concentration and sulfur dioxide released from coal combustion. Control methods: mushroom pesticides with caution, concentration can not be too high when used. In particular, the use of dichlorvos is absolutely not allowed during the fruiting period, and ventilation, air ventilation, and harmful gases are eliminated. 4, shriveled mushroom body was normal at the beginning, in the swelling period that is yellowing, edema or dry shrinkage, and stop growing, and finally become soft rot. The cause of edema is that the humidity is too large or there is more water directly sprayed on the young mushroom body, making the mushroom tissue absorb water, affecting the respiration and metabolism and stopping the growth and death. Shrinkage is due to the relative humidity of the air is relatively small, ventilation is too strong, the wind blows directly on the mushroom body, so that the mushroom loses water and die. Or the nutrient of the culture medium is imbalanced, after forming a large number of primordia, some of them grow rapidly, and the rest are stagnant due to insufficient nutrient supply. Control measures: Control the humidity between 80 and 85%, do not spray water on the young mushroom body, do not let the wind blow directly on the mushroom body. Reasonable ratio culture ingredients. A small number of shriveled mushrooms are due to degradation of the strains, and the symptoms are that the caps have not grown large enough to rewind, yellow, and shrink. Control methods: use good varieties. 5, coral mushroom primordium differentiation is not normal, loose, many small branches, shaped like corals. The reason is that when the primordium occurs, severe ventilation is bad, the light is extremely weak, and the nitrogen source is lacking. Prevention: Strengthen ventilation and light adjustment of carbon and nitrogen ratios and add nitrogen sources.