In order to enable the majority of growers to better grasp the pathogenesis and prevention methods of common diseases in greenhouse cultivation, the Chinese pesticide network Xiaobian is introduced as follows:
1. Powdery mildew 1. Incidence conditions and symptoms The disease is caused by the fungus of the ascomycete monofilament powdery mildew fungus, which mainly damages the leaves, and the leaf surface is sprinkled with a layer of white powder. Finally, the diseased tissue is brown and necrotic. The germs are spread by airflow and watering. Indoor 10-25 degrees can be onset, high temperature drying and alternating heat are beneficial; when the temperature is above 30 degrees, the conidia quickly lose vitality.
2, prevention and control points indoor disinfection. Fumigation with sulfur powder or chlorothalonil before use. Sulfur powder is 0.24 kg per 100 cubic meters, 0.45 kilograms of sawdust, several places, and smoked in the closed shed for one night. The effect of maintaining indoor temperature is about 20 degrees. 45% chlorothalonil smoke agent is used for 250 grams per 667 square meters, 4-5 points, and sealed for one night after ignition.
Biological control with 2% agricultural anti-120 or 2% Wuyincin water 200 times solution, spray once every 7-10 days.
The physical control uses a 27% high-lipid emulsion 80-100 times solution or a Beijing 2B30-50-fold solution, which is sprayed on the leaves to form a film at the beginning of the disease, thereby preventing the invasion of the bacteria and causing the bacteria to die. Spray once every 5-6 days, even spray 3-4 times.
For pesticide control, 45% chlorothalonil can be used, and 200-250 grams of closed room smoke per 667 square meters. At the beginning of the onset, 20% triadimefon EC 2000 times solution, or 30% Teflon WP 2000-3000 times solution, or 5000 times baking soda solution in the early stage of the disease, once every 3-4 days, Spray even 3-4 times.
Other methods have a certain effect on the disease using a high temperature stagnation method. Also pay attention to the timely removal of sick bodies.
Second, gray mold 1, the incidence of symptoms and symptoms The disease caused by the fungus of the fungus Botrytis cinerea, mainly harmful to flowers, young melons, leaves and stems. More intrusion from the defeated female flower, causing the petals to rot, and then to the young melon. At the beginning, the umbilical part is watery, and then the soft rot is atrophied. When the temperature is high, the dense gray mold layer is formed on the flower and the young melon. The incidence of leaves, often appear nearly round, large lesions, a small amount of gray mold, damage to stems, often cause stem rot, torsion. The pathogens mainly rely on hyphae and conidia on the residue and overwinter on the soil surface. Spread by airflow, dew, watering or farming operations. The onset temperature is 18-23 degrees, and the shed temperature is higher than 31 degrees to inhibit the onset; the humidity is greatly affected.
2, prevention and treatment methods disinfection and sterilization before planting, with 20% speed Keling smoke agent or 20% Tec smoke agent 0.5-1 kg / 667 square meters, smoked 12-24 hours, or with 50% speed Keling Wet powder 600 times solution, 65% mefenoid 400 times solution for fine disinfection of the ground, walls, shed film, etc.
According to the pesticide network , ecological control is carried out by mulching or drip irrigation. In the early stage of growth and after the onset, watering should be controlled and air should be released at the right time. In the evening, if the outdoor temperature is at 16 degrees, the air can be cooled and cooled. Bacteria, raising the temperature to 33 degrees.