Symptoms and control points of mushroom verrucosporium disease

Mushroom verrucosporium disease is also known as wet rot, vesicle disease, white rot and so on. It is a common disease in the world. The pathogen is harmful verrucous mildew, also known as condyloma mildew, which belongs to the genus Alternaria, Cercosporaceae, Cercospora. When the mushroom hyphae begins to twist into small mushroom buds, the mushroom buds are most susceptible to infection. The infected mushroom buds become tumor-like interweaving growth of mushroom hyphae and pathogenic hyphae, and the appearance is like a horse. Mushrooms are called mushroom blister, which is generally 3-4 days earlier than normal mushrooms. The symptoms and control points of mushroom verrucosporium disease are as follows:

1. Symptoms of mushroom verrucosporium disease

After long-term study, it was found that the pathogen only infected the fruiting body but not the mycelium. It takes at least 11 days for mushrooms to be infected to the initial symptoms, and the growing hyphae can accelerate the germination of conidia of verrucosporium. In the first crop of mushrooms, the source of infection is usually covered with soil and old mushroom shelves. The disease of the next few crops of mushrooms is caused by water, tools and human operation.

If it is infected during the period of mushroom bud formation, it is shown that the normal mushroom bud has not yet appeared, but the diseased mushroom grows in large quantities and forms a kind of abnormality of puffy tissue, and the diseased mushroom generally produces mushroom 3-4 days earlier than the normal mushroom. If the pathogen is infected in the young bud growth period, although the diseased mushroom can continue to grow, the development of the mushroom cover is abnormal or stops, the stalk is inflated and distorted, and the interior of the diseased mushroom is hollow in the later stage. the junction between the cap and the stalk and the base of the stalk grow white and fluffy hyphae, then turn dark brown, and the surface oozes brown water droplets and rot, and gives off a foul smell.

2. Key points of prevention and control of mushroom verrucosporium disease

1. Soil mulching is the main transmission medium of verrucosporium, so disinfection and soil mulching is the key to control the occurrence of verrucosporium. The soil covering material should be less than 15cm from the surface, so as to avoid bringing diseases and insect pests into the mushroom house. In the areas where verrucosporosis is serious, there are more verrucosporidium spores in river mud and pond mud, which is not suitable for use. After the soil covering material is taken back, it is exposed to the dry state in the hot sun, and 1/1000 formaldehyde aqueous solution is used to evenly adjust the water. About industrial formaldehyde 2Kg is needed for each cubic meter of covered soil, which is adjusted to a moist state, then covered with thin film for one day, and then spread out to dry for one day, so that formaldehyde can be used after volatilization. If the covering soil is disinfected with steam, it can be kept at 65 ℃ for 1 hour.

2. Mushroom house treatment. Mushroom houses should be located away from garbage dumps, pig and cow sheds and other places with more diseases and insect pests. If the culture material carries out secondary fermentation in the mushroom room, it can be sterilized by steam combined with pasteurization. If the secondary fermentation is not carried out in the mushroom room, it can be disinfected with formaldehyde and fumigated for 12 hours according to the amount of 10ml formaldehyde and 2g potassium permanganate per cubic meter. Or fumigate for more than 2 hours with an aerosol disinfection box of 2-4 grams per cubic meter.

3. After mushroom is covered with soil, before mushroom emergence, benzimidazole pesticides are evenly sprayed in the mushroom room and its surrounding environment, which can effectively prevent the occurrence of verrucosporium. The commonly used pesticides are carbendazim, thiophanate-methyl, terketol, decay, verrucine, etc., with a concentration of 500-1000 times. In recent years, the "high efficiency fungicide" developed by Fujian Mushroom strain Research and Promotion Station has been widely used in the province, and the effect is good.

4. Treatment of diseased mushroom bed. If verrucosporosis occurs in a large area, you should immediately stop spraying water and dig up the diseased mushroom and verrucosporium mycelium on the mushroom bed. The mushroom room is fumigated with formaldehyde or aerosol disinfection box for 1 hour, the dosage is the same as above, be careful not to fumigate for too long. Immediately ventilate for 2-3 days after fumigation, wait for the surface of the mushroom bed to dry, and then evenly spray the above benzimidazole pesticides with the same concentration as above. Pay attention to be sure to spray wet spray evenly cover the soil, the surrounding environment should also be evenly sprayed, so that after adjusting the water, you can still produce mushrooms normally. If verrucosporidiosis occurs in a small amount, the mycelia of diseased mushrooms and verrucosporium should be removed in time, and benzimidazole pesticides should be sprayed evenly at the affected site.

5. Strengthen the management of mushroom house, pay attention to ventilation during high temperature and humidity, and dispose of the diseased mushrooms in time.