What medicine is used to prevent and cure brown spot?

Brown spot is a fungal disease caused by Rhizoctonia solani, which is widely distributed all over the world, and can infect all turfgrasses, especially cold-season lawn grasses, causing lawn plant death, causing lawn to form a large area of bald spots, and greatly destroying the lawn landscape. let's take a look at what drugs are used to control brown spot.

Brown spot of lawn

[symptoms] when the disease begins on the lawn, near-round withered grass spots of different sizes often appear. When the conditions are suitable, the disease develops rapidly, and the diameter of subtilis spot can be extended from a few centimeters to one or two meters. As the diseased plant in the center of the disease spot can be recovered, as a result, the subtilis spot is mostly in the shape of "frog eye", that is, the center is green, and the edge is withered yellow band.

[prevention and control] it is necessary to apply little or no nitrogen fertilizer before or during the high temperature and humidity weather, maintain a certain amount of phosphorus and potassium fertilizer, avoid series irrigation and flood irrigation, especially in the evening. When there are withered spots on the lawn, spit (or dew) should be removed as early as possible in the morning to help alleviate the disease. Do not cut grass too low in summer (usually 5-6 cm), over-dense lawn should be properly punched, combed, withered grass and mowed residual grass should be removed in time, disease-resistant varieties should be planted, and timely and effective chemical control should be carried out.

Red and brown spot

[symptoms] the damaged leaves are small yellow-brown spots at first, and sometimes there are dozens of disease spots on one leaf. The small spot gradually enlarged into a disease spot with a diameter of 1 cm to 2 cm, with a light brown inside and a slightly angular and slightly different thickness of the concentric wheel spot. When the disease is serious, the diameter of the lesion can reach 2cm to 3cm. Grayish white woolly mildew occurred in the dark gray part of the transfer between the sick and healthy.

[prevention and treatment] thoroughly remove the diseased and residual bodies and reduce the source of primary infection. Do a good job in the management of temperature and humidity in the greenhouse, pay attention to ventilation and dehumidification, and improve ventilation and permeability.

Tulip brown spot

[symptoms] the infected leaf buds are malformed and curled, and the leaves that grow up after the tender buds are damaged become curly. If the environment is humid, a large number of gray mold conidia will be produced on the diseased tissue, which will affect the nearby healthy plants and make the leaves susceptible, so the growth of the bulb will be greatly affected. After the flowers are injured, white or light yellowish brown spots begin to appear, then expand rapidly and wither, or turn brown and dry. Banding also appears on the pedicel, and the conidium sometimes occurs above it.

[control] remove the diseased bulbs before planting, and carry out rotation planting. Once a bud or bud showing symptoms of the disease is found, it should be removed immediately to control the development of the disease. Before planting, soak the bulb in 2% formalin solution for 30 minutes, dry and plant, in order to reduce residual bacteria. During the growth period, 50% prohydantoin can be sprayed 1000 times or 50% promethrin 2000 times or 50% carbendazim 1000 times.