How to prevent and control edible mushroom diseases? Five-step control method for flower gray mold

Pest and disease control for flowers and trees: Gray mold is an important disease of greenhouse flowers, mainly harming the flowers, fruits and leaves. It often occurs along with the flower growing season, especially during the winter and spring greenhouse growing period. If management is neglected, it is even more conducive to the occurrence and spread of the disease, and in severe cases it can cause a large number of fallen flowers and leaves, affect plant flowering, and reduce ornamental value.

Pathogen and conditions for occurrence: Gray mold is caused by Botrytis cinerea of the Deuteromycotina. The pathogen overwinters as mycelium or conidia and sclerotia attached to diseased plant residues, or left in the soil. The suitable temperature for the development of this fungus is 10°C to 32°C, with a minimum of 4°C, and the relative humidity must remain above 90%. Because the spring temperature is suitable and the humidity inside the greenhouse is high, failure to ventilate in time is the main reason for the relatively severe occurrence of the disease. Main symptoms of the disease: The pathogen invades through the stomata or wounds of the calyx hairs and flower stalks, spreads upward to the fruit stalk, and the fruit skin becomes grayish-white, water-soaked and soft-rotted. When humidity is high, a large amount of gray mold develops on the fruit surface. Diseased flowers falling onto the leaf surface easily cause leaf disease, forming large round spots covered with gray mold. Rotten flowers and rotten fruits falling onto the stems cause stem rot, and in severe cases the plant dies. When chrysanthemum leaves are affected, the leaf edges show brown spots, the surface is slightly wrinkled in concentric rings, the petiole and flower stalk soften first, and then the outer surface rots. When fuchsia leaves are affected, water-soaked spots appear on the diseased leaves and gradually turn dark brown, and then rot. In addition, Gerbera and cyclamen are also susceptible to damage.

Pest and disease control for flowers and trees:

1. Seed disinfection. To kill fungi attached to the surface of flower seeds, the seeds can be soaked in 10% trisodium phosphate solution for 20 minutes, rinsed under running water for 40 minutes, and then used. They can also be soaked in warm water at 52°C for 30 minutes, then dried and set aside;

2. Foreign soil planting. The pathogen mainly overwinters in the soil, therefore, whether for garden planting or pot planting, the soil is required to be disease-free new soil, and the pot soil, flower pots and bulbs must be disinfected;

3. Reasonable fertilization. Apply decomposed organic fertilizer as much as possible, increase the application of phosphorus and potassium fertilizers, improve the disease resistance of the plants, and at the same time pay attention to controlling the amount of nitrogen fertilizer to prevent excessive growth and worsen the disease;

4. Greenhouse management. Remove diseased leaves, diseased flowers and fruits, and yellow leaves in time, keep the greenhouse clean, and ensure good ventilation and light transmission. High-temperature sealing of the greenhouse inhibits the bacteria. In the early growth stage and after the onset of disease, appropriately control watering and ventilate later at the proper time. Raise the greenhouse temperature to 33°C, which is unfavorable for the production and differentiation of spores. Reduce humidity to decrease condensation on the greenhouse roof and leaf surfaces;

5. Chemical control. In the early stage of disease, 45% chlorothalonil smoke agent can be used, or 15% procymidone fumigation for 3 to 4 hours (250 grams per mu of greenhouse). It can also be dusted in the evening with 5% chlorothalonil dust (1 kilogram per mu of greenhouse). For spraying, 65% zineb wettable powder at 500 times dilution can be used, spraying once every 10 days, for 2 to 4 consecutive sprays (interval 7 to 10 days). In the early stage of disease, 50% procymidone at 1000 times dilution, or 50% duomeiling at 1000 times dilution can also be sprayed, used alternately every 7 days, for 2 to 3 consecutive times, all of which can effectively control the occurrence of gray mold.