Harmful Symptoms of Trichoderma Infection in Edible Fungi and Control Methods
Harmful Symptoms The main biological characteristic of Trichoderma is that its mycelium maturation period is very short, often reaching physiological maturity within one week, after which it produces a green mold layer, namely its spore layer. When the substrate is infected, the mycelial stage is not easily noticed, and attention is only drawn when the mold layer appears; at first it is only dot-like or patchy, and when conditions are suitable or the edible fungus mycelium is not very robust, it quickly develops into sheets, until the entire fungus bag or bed is contaminated. If measures are not taken in time, the mushroom shed can become a sheet of green in a short time, its spores fly about, and a large number of Trichoderma spores will also attach to the surrounding shed walls, leaving serious hidden dangers for future production.
Occurrence Pattern Trichoderma mainly survives on rotten wood, dead branches and fallen leaves, soil, organic fertilizer, plant residues and in the air. In many old mushroom houses used for cultivation, contaminated mushroom tools and sites are the main primary infection sources, and the conidia produced by already diseased areas can cause repeated infections many times, making them even more frequent. The incidence of Trichoderma is greatly related to environmental conditions. Trichoderma spores have a higher germination rate at 15-30°C, and the mycelium can grow at temperatures of 4-42°C, growing fastest at 25-30°C. Spores germinate fastest at an air relative humidity of 95%, and are more difficult to germinate when the relative humidity is below 85%. Therefore, under high temperature, high humidity, poor ventilation and when the culture substrate is slightly acidic, Trichoderma is very easy to breed. After Trichoderma infects the host, it competes with the host for nutrients and space, and also secretes toxins to damage and kill the host, winding around and cutting off the host's mycelium.
Control Measures:
When preparing spawn or mixing materials for cooked-material cultivation, add 1:1000 Youmeijing in proportion, and strictly sterilize to thoroughly kill its spores.
Scientifically blend the substrate components to make the nutrition comprehensive and balanced, so as to ensure the health and resistance of the edible fungus mycelium, which can form antagonism or inhibition against mold. Practice has proved that adding Tiantian Gu'Erzhuang in proportion during production is sufficient.
During fermentation cultivation, after adding Youmeijing, the substrate still needs to be fermented evenly to kill or inhibit as many of its spores as possible.
Inoculation operations must be strict and standardized, so that mold spores do not fall into the substrate. Research has found that during inoculation, turning on the edible fungus inoculation purification machine for 5 min before operating gives a production effect similar to conventional formaldehyde fumigation, and also eliminates formaldehyde irritation to the human body and avoids the possibility of formaldehyde residues.
During the spawn-running or fungus bag incubation period and the fruiting period, spraying 30-50 times Jinxing disinfectant or 1:1000 Youmeijing on the empty areas of the mushroom shed about every 5 days is currently the most effective preventive method.
After discovering Trichoderma, promptly spray or inject and smear 1:500 Youmeijing on the contaminated areas and fungus bags, with remarkable effect. Seriously contaminated fungus bags should be incinerated or deeply buried in time.