Prevention and Control of pests of Edible Fungi in Winter

Recently, there have been many consultations on the problems of edible mushroom pests planted in autumn. through field investigation, it is found that edible mushroom pests have occurred relatively seriously this autumn, and some mushroom sheds have almost become "insect sheds", which have caused a large number of miscellaneous bacteria pollution and serious diseases. Mushroom farmers have suffered heavy losses. According to the results of the investigation, experts are invited to introduce to mushroom farmers about the "prevention" and "treatment" of pests in autumn and winter, in order to reduce the losses of mushroom farmers.

Species and identification of insect pests

1. Mushrooms, mosquitoes, mushrooms and flies: fermentation materials are generally used for cultivation in autumn, such as Pleurotus ostreatus, Coprinus comatus and Pleurotus ostreatus. Adults such as small mushroom mosquitoes, Pleurotus ostreatus mosquitoes, mushroom eye mosquitoes, stinging mosquitoes, heterotypic eye mosquitoes, fecal flies, flea flies and fruit flies can not directly cause harm to adults and eggs. When the temperature is 16 ℃ ~ 30 ℃, the eggs hatch into larvae in about 4 days, and the larvae feed on hyphae or fruiting bodies, and the larvae pupate in 7 ~ 18 days. The pupal period is about 2 ~ 8 days, and then the adults can mate again on the same day or the next day after Eclosion. The general variety body length can be more than 3.5 mm, the maximum can be more than 6 mm, the larva body length is generally about 5 mm, the maximum can be more than 16 mm. The body size of mushroom flies is too small. The adult length of the largest flea fly is only about 1.5 mm and the larva is between 2 mm and 3 mm, but the length of adults and larvae of Drosophila melanogaster is about 5 mm, which is almost the same as that of mushroom mosquitoes.

The adults of the above pests have strong phototaxis and taste (mushroom flavor, material flavor, rotten flavor). When the mushroom shed is treated with closed light, the occurrence probability is low, and the population density decreases greatly. At the initial stage, the larvae move in the surface material and bite the hyphae, and after mushroom comes out, they can drill to the base of the stalk until the cover is covered. After the mushroom body is "hollow", it goes back to the material and continues to do harm until all the hyphae in the base material are nibbled away.

2. Mites: there are many sources of mites, or live in the cracks in the inner corner of the shed, can also survive in column cracks, bamboo and wood cracks, and can also enter the mushroom shed through various tools, and some of them can also be spread through bacteria (mainly third-class species). In short, there are many channels to enter. The main harm of mites is to bite the hyphae, but when the population density is high, they can also bite the mushroom buds and mature fruiting bodies. The main species of mites are acaroid mites, acaroid mites, spike mites and so on. The individual mite is extremely small, but the pest has a social habit, and it moves in clusters on the material table, the edge of the mushroom shed and the ground. when the population density is very high, the material surface is white (dark white) or flesh red or even reddish brown.

The reproduction rate of mites is very fast. It takes about 8 days to complete the first generation at the temperature of 20 ℃ ~ 30 ℃, while it takes only 3 days for some varieties to complete the first generation. Due to different varieties, some mites also have to go through the growth stages of eggs, young mites, nymph mites and adult mites, but some varieties can only be divided into eggs and mites, because their eggs can directly develop into adult mites in the mother, and then break out. When the living conditions are uncomfortable, or aseptic or edible, it can be adsorbed on tools, the human body and even other insects, and take the opportunity to transfer to a suitable place to continue its survival and reproduction.

3. Jumper: it is more harmful than in summer and autumn, can survive under the condition of more than 15 ℃, becomes active gradually when the temperature reaches 22 ℃, and propagates and expands with it. The jumper takes the mycelium and fruiting body as the harmful object, and lurks in the bacterial fold and small crevice, which greatly reduces the value of the product and even scraps it. There are many kinds of jumping insects, and the common ones are horned jumping insects, black horn jumping insects, black flat jumping insects and so on. The lifespan of jumpers is very long, with most species surviving for about half a year and elders up to one year. The main physical feature of the jumper is that it is tiny, usually about 1.5 mm, and the largest is less than 5 mm. The moist environment, dark light, rich hyphae and mushroom nutrition in the mushroom shed provide the best conditions for the reproduction of jumping insects.

4. Nematodes: nematodes mainly harm the mycelium of edible fungi, and there are also many kinds of nematodes, such as mycelium nematodes with oral needles, small rod nematodes without needles and so on. The former inserts the mycelium into the mycelium to absorb the mycelium juice, which hinders the growth of the mycelium, then shrinks and dies, resulting in the phenomenon of "disinfection". The latter quickly agitates the mycelium with its head, making it into very fine mycelium fragments, and then swallowing or sucking, resulting in the same disappearance of hyphae. The nematode is tiny, usually about 1 mm, but its reproduction rate is very fast. Generally, under the condition of 20 ℃ ~ 30 ℃, it can lay eggs about 30 hours after mating, and a female can lay dozens of eggs, up to 140. it only takes more than ten days for eggs to develop to adults and only about 8 days for eggs to develop to adults above 25 ℃. Nematode pests have smooth body surface, like water-stained environment or large water living conditions, and there seems to be a mass of water moving when they move, which is an important method to identify nematodes.

Autumn production also has other pests or small animals can form a certain degree of harm, such as snails, mouse women, mole cricket and so on. The prevention of insect damage is a positive attitude to control pests in the production of edible fungi, and the effect is excellent. The main measures are: base material fermentation stage: first of all, the use of anti-insect net to prevent insects from spawning is an economical, effective and simple measure, and at the same time effectively solve the problem of drug residues. Choose the anti-insect net used in general vegetable breeding, even tiny mushroom flies can not get into it. Secondly, often spray efficient, low-residual drugs on the material surface to ward off insects, but the concentration should be low, the amount of spraying should be less, so as not to produce drug residues. Thirdly, the clinker cultivation method should be adopted as far as possible to control insects and kill miscellaneous bacteria and germs at the same time, killing more than one stone. Finally, in the cultivation of Pleurotus ostreatus and Agaricus blazei Murrill mushrooms, the popularization and application of secondary fermentation technology at a temperature of more than 60 ℃ for about 2 days will kill all living insects, including eggs, larvae and adults. Although the production cost has been slightly increased, it has many effects, such as killing insects, killing (inhibiting) bacteria, uniform maturation of base materials, removing peculiar smell and so on.

Sowing stage: a considerable number of insect pests invaded at this stage, which generally lasted for about 3 ~ 5 weeks. Pleurotus ostreatus, Coprinus comatus and other bacterial bags were bound with micropores, which could completely meet the entry and exit of mushroom mosquitoes and mites without restriction. First of all, the high-density window screen (such as anti-insect net) encapsulates the doors, windows and vents of the bacteria room, and insists on closed light culture to prevent adults from entering. Secondly, always check whether there are adults in the room. Once found, spray pyrethroids with low concentration drugs to kill them. Even if water is simply sprayed on the wings of mushrooms and mosquitoes, the adults can fall to the ground and cannot fly again, and they can also be killed. Finally, when the environment around the culture room is poor, such as close to garbage, stable toilets, dung piles, etc., in addition to cleaning and prevention as much as possible, indoor insecticidal drugs should be often sprayed on the space and walls, which is also a very effective preventive measure. Mushroom management stage: first, mushroom shed doors and windows and vents encapsulate high-density window screen (anti-insect net) to prevent adults from entering. Second, try to reduce the light in the shed. Third, the management of water use adhere to the use of well water or tap water, without the "stagnant water" in ditches, bays and ponds. Fourth, the entrance and exit ground is sprinkled with lime belt 1 ~ 2 meters wide to prevent mites, rat women and other pests and small animals from entering. Finally, during the interval of mushroom emergence, proper spraying of pyrethroids, combined with formaldehyde and bleach, has the dual functions of insect and bacteria prevention, but in the growth of fruiting body, any drug should be prohibited to prevent drug residue from affecting the quality.

Source of pests: in the cultivation and production of edible fungi, most pests enter the base material in the form of eggs, a small part of which lay eggs in the base material and then sow, while most of them lay eggs after sowing. It is less likely to enter the sowing stage with live larvae (or live insects) through the strain. The hatching of eggs is carried out synchronously with the bacteria in the base material, and it is generally impossible to detect or identify them with the naked eye. At first, the individual population of larvae is small, and the amount of mycelium eaten is very small, so it is not easy to attract attention. when the larvae continue to grow, and with the expansion of the population, the harm to the hyphae is serious, it has reached the first tide to produce mushrooms or enter the peak stage of mushrooms, and it is difficult to detect until the second tide of mushrooms is difficult, or even no longer produce mushrooms, and when the mycelium on the surface of the substrate disappears and turns brown, it is found that it is caused by pests. A considerable number of producers found pests at this stage. Another characteristic of pests in autumn and winter is that with the gradual decrease of air temperature, insects are also looking for warm shelter, which is more suitable in the base material, and the temperature in the culture room and cultivation shed is also more suitable. After finding a suitable "place to live", it propagates rapidly, causing the population of pests to expand rapidly.

Harmful symptoms: the pests on edible fungi live by biting mycelium in the early stage, and "eat all" with the fruiting body in the later stage. When the occurrence is serious, the surface of the substrate changes from white to yellow, brown, or even black. The surface and even the interior are densely covered with pest excreta, and the base of the fruiting body until the whole stalk is bitten into a sponge, and even there are wormholes on the lid. On the other hand, pests can cause some diseases or miscellaneous bacteria to spread. Such as the disappearance of hyphae on the surface of the substrate and the spread of insect excreta. After causing decay, miscellaneous bacteria such as Trichoderma and Rhizopus take advantage of the opportunity to enter, which is easy to produce diseases; insect bites on the fruiting body lead to the death and decay of young mushrooms (mushroom buds), and it is also easy to attract external adults to enter, with a number of bacteria or fungi on the insect body. while increasing the density of pests (insect population), it also brings a large number of germs to the already damaged edible mushroom production.

The method of killing pests: timely find insect pests and take measures to kill them, we should strictly select drug varieties, not only pay attention to the problem of drug residues, but also prevent drug damage. If the initial pest density is very small, it can be killed by using pyrethroids with high efficiency and low residue, air or material surface covered with soil spray.

When the occurrence is moderate, part of the eggs will be laid in the material, and the fruiting body can be lighted at one time, and the mushroom mosquitoes and jumping insects will be sprayed with 800x DDV on the material surface and the soil layer, and the film will be covered for 3 hours to 5 hours; for mites, 1000 times of acaricides, such as acaricide, acaryl alcohol, etc., will also be covered for several hours; for nematodes, 0.5% formaldehyde solution will be re-sprayed, and the film shall also be covered for 2 hours to 4 hours.

When there are brown patches on the material surface and moth on the fungal stalk, it has occurred seriously. At this time, the larvae are mostly in the material, spraying drugs are generally ineffective, and aluminum phosphide "through killing" measures can be used to kill all at once. The method is as follows: the fruiting body is all lighted, and when the bacterial wall is cultivated, the bacterial wall is covered with plastic film, a piece of aluminum phosphide is placed on both sides at an interval of 1 meter, and the plastic film is quickly compacted with soil for about 8 hours to 10 hours. For the insecticidal methods of fungus bed cultivation, refer to the above. Points for attention: the operation should be fast; the film should be compacted; when removing the film, the doors, windows and vents of the mushroom shed should be opened first. Then lift the plastic film, wait for 1 hour to 2 hours later, and then move the plastic film out of the shed, carefully pick up the aluminum phosphide waste, bury it deeply, and do not throw it away.