Detailed Explanation of Prevention and Control Techniques for Major Diseases of Edible Fungi

There are already more than 100 species of contaminating microorganisms in edible fungi, and the most common and seriously harmful ones mainly include more than 20 kinds such as Trichoderma, Neurospora, Mucor, Aspergillus, Penicillium, and bacteria. The symptoms and prevention and control measures of several major diseases are briefly described below:

I. Trichoderma

Trichoderma, commonly known as green mold, can harm almost all edible fungi. Its harm to edible fungi is shown as follows: it contaminates the substrate and competes with edible fungi for nutrients and space; it secretes toxins that injure and kill the host; when Trichoderma hyphae contact the host hyphae, they entangle and cut off the host hyphae. The prevention and control methods adopted are:

1. The culture room and cultivation site should maintain a low temperature, with relative air humidity controlled at around 85%, and should remain clean and hygienic with good ventilation.

2. Once Trichoderma damage occurs, ventilation should be carried out immediately to reduce humidity. In the early stage of infection of the fungus logs, injection with 2% aldehyde solution or 3-5% carbolic acid can be used to inhibit the expansion of Trichoderma. For some infected mature fungus logs, the contaminated parts can be dug out, and lime powder, lime-sulfur mixture, or Bordeaux mixture, etc., can be spread on the treated areas. Fungicides such as carbendazim, prochloraz, and thiophanate-methyl can also be used for prevention and control. For example, mixing 1000 parts of 50% carbendazim into the substrate can prevent the occurrence of Trichoderma, but carbendazim should not be used on lion's mane mushroom, wood ear, or silver ear.

II. Neurospora

Neurospora, commonly known as pink mold disease or red bread mold disease, is a common contaminating microorganism in edible fungi production. It can contaminate all edible fungi and is a tenacious, fast-growing aerial mold. After the substrate is contaminated, it rapidly forms an orange-red or pink mold layer on the surface of the substrate. The prevention and control measures adopted are: try as much as possible to avoid production during the hot, stuffy, and humid high-temperature summer period, and pay attention to good environmental sanitation. Once orange-red block-like conidial masses appear, carefully wrap them with a damp cloth or damp paper and remove them, then immerse them in medicinal solution or bury them deeply. Never spray fungicide directly on the pathogen with a sprayer, so as to avoid scattering the spores; appropriate amounts of formaldehyde, kerosene, or diesel can also be dripped on in time, and then wrapped with plastic film, which can cause the mold to rot and die. If damage occurs in the later stage of mycelial growth, the affected fungus bags can be buried in soil with poor air permeability at a depth of 30-40 cm. After 10-20 days of oxygen-deficient treatment, the disease can be reduced and mushrooms can still be produced. Fungicides such as carbendazim and prochloraz can control the growth of Neurospora.

III. Aspergillus and Penicillium

Aspergillus is commonly known as yellow mold, green mold, black mold, etc. There are many species of Aspergillus. The colony of Aspergillus niger is black, loose, and granular; Aspergillus flavus is yellow or yellow-green, and finally brownish-green; Aspergillus glaucus is initially white and later grayish-green; Penicillium has many species, and its colonies appear as grayish-green, yellow-green, or blue powdery mold layers. Aspergillus and Penicillium are both common contaminating microorganisms. They compete with edible fungi for nutrients and moisture, and secrete toxins that inhibit the growth of edible fungi. The prevention and control measures adopted are: strengthen ventilation in the culture room, lower the temperature, and reduce relative air humidity. For localized occurrence, 5-10% lime water can be used for washing. For other prevention and control methods, refer to the prevention and control of Trichoderma.