The treatment of seeds with drugs can control the disease of rice evil seedlings.

Evil seedling disease occurred in many places in Tongzhou District of Nantong City last year. The occurrence characteristics, infection ways and control techniques of the disease are introduced as follows.

Evil seedling disease occurred from seedling stage to heading stage, especially at tillering stage. Seed-borne bacteria was the main source of infection, followed by diseased rice straw. Sow germ-carrying rice seeds or cover with diseased straw. When the rice seeds germinate, the pathogen invades from the coleoptile and causes the disease. Although Evil seedling disease can cause re-infection, the pathogen mainly invades in the early stage, that is, the rice coleoptile stage, and the possibility of infecting healthy plants to cause rice seedling disease is very small.

Rice evil seedling disease is mainly caused by seeds carrying bacteria, and the soil does not carry bacteria, so there is no need to treat the diseased soil with pesticides. The treatment of seeds before sowing is the most effective measure to control the disease. At present, the main drugs registered for seed soaking to control evil seedling disease are prochloraz, dithiocyanate, cyanothrin, doxorubicin, etc., among which prochloraz, dithiocyanate and their mixtures are the most commonly used. Due to the use of benzimidazole fungicides and their mixtures represented by carbendazim for many years, rice evil seedling disease bacteria have a high resistance to this kind of drugs, and prochloraz also has a potential risk of drug resistance. In recent years, 25% cyanothrin suspension developed by Jiangsu Pesticide Research Institute Co., Ltd. has been registered for the control of rice evil seedling disease, and the recommended concentration of seed soaking is 83.3 mg / L. The drug has a good control effect on rice evil seedling disease and can effectively kill the pathogen of rice evil seedling disease which has become resistant to carbendazim and other benzimidazole drugs.

In production, the seeds should be dried for 1-3 days, and the seeds should be soaked after seed selection. Generally, the seeds are soaked for 48 hours at normal temperature and 60 hours when the temperature is low. The concentration of rice seeds or susceptible varieties should be appropriately increased when soaking seeds. Lowering the temperature or soaking seeds without accelerating germination and sowing seeds can reduce the occurrence of rice evil seedling disease to a certain extent. Instead of using diseased rice straw as the mulch for seed germination, concentrated high temperature composting or burning of diseased rice straw can reduce the pathogen of rice evil seedling disease.