Occurrence and Control of Black-streaked Dwarf Disease in Spring Maize

Black-streaked dwarf disease is a virus disease transmitted by the gray rice lice. The seedling stage is the main susceptible stage. Since 1990s, with the change of planting structure, black-streaked dwarf disease of single cropping rice and spring maize in Chun'an County has been aggravated year by year. Especially since 2000, black-streaked dwarf disease of rice has occurred widely in the whole county, and has been epidemic in some areas. The average cluster incidence rate in serious areas has been above 20%, and the serious fields are nearly 50%. The disease has become a rice, A disastrous disease in spring maize production. It is expected that this year the black stripe dwarf disease is still showing an aggravating trend. All localities should pay attention to it and do a good job in prevention and control scientifically and effectively. 1, agricultural control measures 1, to prevent sporadic sowing, seedling field to contiguous. 2. To prevent early sowing, the sowing time of single cropping rice should be fixed after the last ten days of May, so that the susceptible period of single cropping rice (3-5 leaf stage) can avoid the peak period of emergence and migration of the first generation of gray rice planthopper--about 20 May. II. Pest control and disease prevention Black-streaked dwarf disease is transmitted by whitefly, so control of whitefly can effectively prevent black-streaked dwarf disease. 1. Imidacloprid seed soaking: soak seeds for 48 hours according to the conventional method. After picking up dry water, mix 10g of 10% imidacloprid wettable powder evenly in 1 kg (measured by dry seeds), and then germinate normally. 2. In the serious occurrence area, the second and third times of control of gray rice lice were continuously carried out in the seedling stage of spring corn and single-season rice, and once more in the early stage of the field, spraying 10% imidacloprid WP 15g/mu mixed with 45kg water. Imidacloprid seed soaking and spraying can also effectively control rice thrips and other insects.