Comprehensive Control Methods for Diseases, Pests, and Contaminant Organisms in Edible Fungi

Comprehensive control of diseases, pests, and contaminant organisms in edible fungi refers to the coordinated application of ecological, biological, physical, chemical, and other factors to control diseases, pests, and contaminant organisms. Its basic guiding principle is prevention first, that is, without damaging the ecological environment, by rationally arranging the production layout for mushrooms, selecting superior varieties, adopting scientific cultivation and management measures, and choosing economically effective control methods, an integrated organic control system is formed to achieve the goals of reducing damage and improving benefits. The main measures for comprehensive control of diseases, pests, and contaminant organisms in edible fungi are introduced below.

I. Rationally arrange the production layout. Implementing rotational cultivation of different mushroom types has a certain effect on reducing the occurrence of some diseases. In areas where grain-mushroom or vegetable-mushroom rotation is practiced, it is best to change the site every year to reduce the residual amount of diseases, pests, and contaminant organisms at the cultivation site and lessen the damage.

II. Select superior spawn. Varieties suitable for the local climate conditions and with strong resistance should be selected for cultivation. Inoculate with spawn that is pure in strain characteristics, has robust mycelial growth, carries no fungal viruses, and is free from contamination by contaminant organisms and pests.

III. Prepare high-quality culture material. The raw materials used for growing mushrooms (or wood ear fungi) must be fresh, free from rot and mold, and fully dried. After log sections are cut, some branches and leaves may first be retained, and the bark should be protected as much as possible; the cut ends and other wounds should be coated with lime water to reduce bacterial contamination. Before composting substitute materials for cultivation, they should be sun-dried for 1-3 days to kill some harmful microorganisms and pests in the material.

IV. Improve sanitary conditions. Composting and cultivation sites should be far from pollution sources such as fermentation yards and livestock sheds, and should be disinfected regularly. At the entrance of mushroom houses (sheds), a disinfectant solution trough or lime pit should be provided for foot disinfection. Workers should wear work clothes when entering. Work clothes and all tools should be disinfected regularly. Before bringing in materials, the walls, bed frames, and floor inside the mushroom house should be thoroughly disinfected with 1:800 carbendazim solution and 0.5% dichlorvos solution to kill latent pathogenic contaminants and pests. Where conditions permit, filtration devices can be installed at ventilation openings to reduce the content of pathogenic and contaminant spores in the air of the mushroom house.

V. Ensure proper sterilization of culture materials and casing soil

Culture materials for raw material cultivation are best subjected to secondary fermentation: the first fermentation is carried out outdoors for 10-20 days, during which the pile is turned 3 times; the second is carried out indoors on bed frames, requiring doors and windows to be closed tightly and heating with steam or a coal stove so that the indoor temperature remains within the range of 60-70°C for 30 minutes. Culture materials for sterilized substrate cultivation must be thoroughly sterilized; if atmospheric pressure sterilization is used, it requires more than 8 hours, and high-pressure sterilization requires more than 2 hours, while ensuring uniform heating. Casing soil materials should be treated with agents such as carbendazim and formalin; or when materials are brought in, they may be placed indoors and pasteurized using the high temperature during secondary fermentation.

VI. Sow at the proper time and appropriately increase the inoculation amount. Except for straw mushrooms, in general, sowing should be chosen as much as possible when the temperature is relatively low, and inoculation can be arranged at night. The inoculation amount should be appropriately increased so that the mycelium quickly covers the culture material, thereby reducing opportunities for contamination by competitive contaminant organisms.

VII. Strengthen management of the cultivation site. Improve environmental conditions, meet the growth requirements of mushrooms as much as possible, and enhance their ability to resist pathogenic bacteria and contaminant organisms. The cultivation site should be frequently ventilated to keep the air fresh, and temperature and humidity should be adjusted well according to the requirements of different mushroom types. During the cultivation period, spray or sprinkle daily with 0.2% soapy water, 3%-4% lime water, or 5% formaldehyde solution; pay attention to inspecting cultivation bed frames or log sections, and promptly dig out and destroy diseased mushrooms or contaminant organisms when found, and disinfect the dug openings with lime water or similar.

VIII. Use physical methods for pest control. Insect-proof mesh screens should be installed on doors, windows, and ventilation openings of cultivation facilities such as mushroom houses, mushroom sheds, and air-raid shelters; indoors, black light lamps can be used to trap insects, but care should be taken to turn off the lamps when opening doors to prevent attracting insects from outdoors.

IX. Use chemical agents appropriately. In cultivation sites and old production areas with severe disease and pest problems, pesticides with high efficiency, low toxicity, and no adverse effects on the growth of edible fungi may be selected for control. Commonly used agents include: (1) mix 50% carbendazim 1000-fold solution into materials, into casing soil materials, or spray the surface after casing to kill many harmful fungi; (2) spray 65% zineb 1000-fold solution on mushroom beds (may contact the mushroom bodies) to kill many pathogens and contaminant organisms; (3) use 1000-fold derris extract solution for indoor spraying to control shell insects, mushroom flies, springtails, and others; (4) use 1000-fold tetradifon solution for spraying in mushroom houses or soaking log sections to effectively control mites; (5) mix 30 g of 10% fenamiphos granules per ton of culture material to kill nematodes; (6) add 1.5-3 kg of metaldehyde to every 50 kg of soybean cake bait to make poisoned bait and place it indoors to trap and kill snails and slugs; (7) spraying the ground of the cultivation site in the evening with 5%-20% salt water can also kill snails and slugs.