Integrated control techniques of edible fungi diseases and insect pests

Edible fungi belong to large fungi, and the environmental conditions needed for their growth and development are suitable for the occurrence and growth of many diseases and insect pests. If we do not pay attention to the control of ecological environment and do not take necessary preventive measures in the early stage, miscellaneous bacteria and various pests will occur in large numbers. In cultivation, it is very important for high quality and high yield of various edible fungi to follow the comprehensive control policy of mainly agricultural control, reasonable combination of biophysical methods and chemical control as remedial measures, and to give full play to the complementary advantages of various control methods.

1. Common diseases and insect pests in edible fungi production

1.1 Brown rot is also called blister disease, wet blister disease, etc.(Figure 1). It mainly harms mushrooms, straw mushrooms, oyster mushrooms, etc. The disease is caused by the fungus Verrucaria sp. Conidiospores and chlamydospores of verrucaria only infect fruiting bodies, but not mycelium. Fruiting body by mild infection, the stalk swelling into vesicular deformity, so called wet vesicular disease. But the disease is different in different developmental stages of fruiting body. The fruit bodies are infected when they are undifferentiated. Then there is a kind of irregular tissue block such as scleroderma puffball shape, covered with a layer of white velvety hyphae, and gradually become dark brown, often exuding dark black juice drops from the diseased tissue; after the differentiation of the cap and stipe infection, the stipe becomes brown, and there are two kinds of white hyphae growth on the infection fold. Verrucospora is a common soil fungus, which is mainly carried by soil, air, operators, tools, insects, rats and so on to infect bacterial beds and bacteria blocks.

1.2 Fusarium wilt, also known as death blight, is a physiological disease. It mainly harms mushrooms, pleurotus ostreatus, pleurotus ostreatus, mushroom, mushroom and so on. The main characteristics are: after mushroom bud formation, fruit bodies of different sizes can occur this disease. After the disease stops growing, yellowing, gradually shrinking, softening, drying, and finally dying or rotting. The main reasons are that the culture material is too dry after the formation of the primordium, which makes the mushroom bud wither; or the mushroom is too dense; the nutrient supply is insufficient, which makes some small mushrooms die; or the temperature of the mushroom house is too high, the ventilation is not good, and the oxygen is insufficient, which makes the carbon dioxide content in the air excessive; and the small mushroom bud is accidentally injured when picking mushrooms, or the mushroom is excessive, thus causing phytotoxicity.

1.3 Deformity mushroom disease is also a physiological disease. During the formation of fruiting bodies of edible fungi, if they encounter adverse environment and conditions, which make the fruiting bodies unable to develop normally, they will be deformed (Figure 2). The main characteristics are: small and thin cap, slender handle, early opening umbrella. This phenomenon occurs after the first crop of mushroom, while mushroom occurs in the first crop. The main causes are high temperature, insufficient light, lack of nutrition and so on.

1.4 Damping-off disease, also known as blight, is a fungal disease. It is mainly caused by Fusarium oxysporum and Fusarium phaseoli. The main disease is that after the fruit body is infected, the pith of the stalk shrinks and turns brown, and the mushroom body is short and no longer grows. The early stage of this disease and healthy mushrooms are not easy to detect in appearance, but the cap darkens, the mushroom body no longer grows, and finally becomes a stiff mushroom. Route of infection: Because Fusarium can survive in the soil for a long time, soil infection is the main route of infection, and it can also be transmitted through the air and some utensils.

1.5 The main pests of edible fungi are mosquitoes and mites. Mites are not easy to see with naked eyes in the early stage, mainly damaging hyphae, causing hyphae to break and atrophy. Mites can be brought into the pile and cover, causing serious harm. Control methods: mite production and culture materials, covering soil, bacteria, etc., it is necessary to carry out integrated control.

2 Integrated control measures

2.1 agricultural control

2.1.1 Select high-quality disease-resistant varieties. Select suitable for local high-quality strains, hyphae robust non-aging, pure, pollution-free. The mother seed should not be passed through 3 generations, and the cultivated seed should be transferred from the original seed.

2.1.2 Reasonable rotation. Different mushrooms, or different varieties of the same mushroom, can produce metabolites with mutual antagonism, and have certain inhibition and killing effects on diseases, insect pests and miscellaneous bacteria. Reasonable rotation can play a better preventive effect; if conditions permit, mushroom farmers can replace new sheds every year, and the effect of impurity prevention is better.

2.1.3 Keep away from infectious sources and do a good job in environmental sanitation. Before production every year, mushroom farms are thoroughly cleaned to eliminate pest breeding sites. The cleaning scope includes mushroom houses and courtyards. The waste mushroom bags, straw piles, compost and all organic wastes of the previous year shall be collectively burned or transported away, and weeds and peat soil shall be eradicated. 40kg water was sprayed with 80% dichlorvos 15ml and 1.8% azithromycin 5ml in the evening. After an interval of 1 week, apply it again. Whitewash mushroom houses with bleaching powder and lime paste, sprinkle dry lime powder in the courtyard.

2.1.4 Reasonably adjust the relationship between temperature, humidity and gas. Temperature, humidity and oxygen are important environmental factors affecting the quality and yield of various edible fungi. During the mushroom growing period, under the appropriate temperature, such as Coprinus comatus 16-24℃, Agaricus bisporus 14-16℃, the number of fruiting bodies is the most, the yield is the highest; the moisture content of the material is 60%-70%, the relative humidity of the air is controlled at 75%-80% during the mycelium growth period, and the fruiting body stage is 85%-90%. When it is lower than 60%, it is easy to roll back, and when it is higher than 95%, it is easy to cause disease. Edible fungi belong to aerobic microorganisms and need fresh air throughout their development, especially during the formation of fruiting bodies. Mushrooms with poor ventilation, too damp and too high temperature are easy to breed miscellaneous bacteria and pests.

2.1.5 Physical control. The armyworm can be smeared with 40% polypropylene viscose in strong light, or sweet and sour liquid to trap and kill edible fungi mites; the fungus midges can be caught manually; the fungus bags with gall midges can be exposed to sunlight for 1-2 hours or sprinkled with lime powder. Water immersion method can also be used to control pests. Water can be injected into bottles and bags for bottle cultivation and bag cultivation. For block cultivation, the cultivation blocks can be immersed in water and pressed with heavy objects for 2-3 hours. After soaking, the bottles and bags can be drained and placed in the same place. Mosquitoes and moths can be trapped by black light or energy-saving lamps.

2.2 chemical control

2.2.1 Control of Aspergillus spp. Timely waste removal is key to controlling Aspergillus (Figure 3). The seed bottle should not be overfilled, and the material should not contact with the tampon. After bottling, wash the bottle mouth to remove organic matter and keep the tampon clean. Carbendazim at 5mg/kg inhibited the growth of Aspergillus niger and Aspergillus flavus, but only after mushroom harvest.

2.2.2 Control of Trichoderma spp. Trichoderma spp.(Figure 4) has no ideal radical drug up to now. It is called cancer of edible fungi. Commonly used fungicides (carbendazim, chlorfenapyr, thiophanate-methyl, etc.) can only inhibit Trichoderma spp., but cannot kill Trichoderma spp. fundamentally. Increasing the dosage will kill Trichoderma spp. and Pleurotus ostreatus hyphae at the same time. Therefore, it is the fundamental measure to control the harm by creating the growth conditions suitable for mycelium growth but unfavorable for Trichoderma reproduction. Once Trichoderma harm occurs, ventilation and cooling should be carried out immediately. Plant ash should be used to cover the place where mold is produced to prevent mold spores from scattering so as to inhibit the expansion of pathogenic bacteria. After the culture material in the stage of bacteria infection, the method of locally smearing liquid medicine can be used to inhibit the expansion of Trichoderma. The commonly used liquid medicine includes 5% carbendazim, 2% formaldehyde, 50% carbendazim diluted 200 times or 75% thiophane methyl and 10% lime water. In addition, lime powder should be sprinkled on the contaminated place. The control effect is also very good.

2.2.3 Control of green mold. Reduce the temperature and humidity of mushroom house, increase ventilation, cover mold place with plant ash, cut off mold spore flying transmission. Take 9 parts of quicklime, 1 part of carbendazim, and an appropriate amount of water to brush the mold. When cultivated uncooked, adding 100g Clomid per 100kg dry material can completely prevent and eradicate mold breeding. After sprinkling potassium permanganate particles on the mold, spray water on the periphery of the mold. Soak mold in 5% lime water, remove lime water after mold disappears, add new material; also soak mold in water directly. Brush 95% alcohol or kerosene on the mold, ignite and burn it, then dig it out and fill it. The culture medium should be sterilized thoroughly, and the temperature, pressure and time should meet the requirements; after the culture medium is done, put it in an incubator at 30℃ for 1 day before use to ensure no bacterial infection. If there is infection, it can be sterilized again. The mother bacteria or stock must be free from bacterial contamination. Antibiotics can be added to the culture medium, generally containing 100-200 units per ml.