The Study Of Chemical Control Techniques Of South Rice Black-streaked Dwarf Virus

Southern rice black-streaked dwarf disease was a new kind of rice virus disease in recent years, the disease was increasing in China, part of the region was outbreaking, resulted in serious economic losses to rice production. At present, it was not entirely clear of the outbreak reasons and epidemic regularity to southern rice black-streaked dwarf disease, at the same time, lack of effective measures for prevention and intervention. Therefore, to confrount the status of southern rice black-streaked dwarf disease in large area, it was important to figure out prevention and control technology on southern rice black-streaked dwarf disease.This paper studied the seed coating agent for the safety of rice growth and the6control efficacy to Sogatella furcifera Horvath、seed coating agent and virus inhibitors、 seed coating agent and the toxticity to kill Sogatella furcifera Horvath in the field、insect nets and toxticity to Sogatella furcifera Horvath, to prevent and control efficacy of southern rice black-streaked dwarf disease, finally, form the Hunan province of southern rice black-streaked dwarf disease chemical control scheme. The results showed that:Using60%imidacloprid FS,70%thiamethoxam FS,25%pymetrozine SC, seed coating agent at different doses to the germination of rice seed, the indoor and outside test results showed that:it could promote root growth, the lengths were16.18cm,16.46cm,15.44cm, longer than that of CK (14.42cm); increase fresh weight at0.446g,0.436g,0.445g, heavier than that of CK (0.398g); inhibited the plant height slightly:33.53cm,34.67cm,34.52cm, higher than that of CK (36.78cm) on rice seed; rice seeding rate was not affected. through the use of60%imidacloprid FS (Youban)1g a.i./kg dry seeds,2g a.i./kg dry seeds,4g a.i./kg dry seeds,8g a.i./kg dry seeds showed that seed treatment of rice field experiment, performanced safety on rice seeding period.With60%imidacloprid FS,70%thiamethoxam FS,25%pymetrozine SC, and other3kinds of seed dressing agent, it could effectively control Sogatella furcifera Horvath occurrence on rice seeding period, control efficacy were82.53%,82.21%,68.75%. Treatmented rice seeds germination of60%imidacloprid FS (Youban) and10%imidacloprid WP2g a.i./kg dry rice seed, the effective ingredients of imidacloprid in leaf sheath’s residual period was not the same,7days after sowing respectively were0.1074mg/kg and0.0733mg/kg;21days after sowing,10%imidacloprid WP has not detected the content, and the60%imidacloprid FS has the content of0.0147mg/kg. The control efficacy of Sogatella furcifera Horvath was not the same, After sowing imidacloprid60%FS28days, the control efficacy was above80%, and the control efficacy of10%imidacloprid WP decreased over time, sowing after28days was11.54%.Control efficacy of southern rice black-streaked dwarf disease:With the control efficacy of60%imidacloprid seed dressing agent dressing only58.97%, or in the seeding stage25%pymetrozine kill Sogatella furcifera Horvath control efficacy was only62.07%, or control efficacy of spraying harpin virus inhibitors was only51.73%, therefore, they were not good control southern rice black-streaked dwarf disease.Use seed dressing agent of imidacloprid and spray to kill planthopper chemicals in the seeding stage on southern rice black-streaked dwarf disease,the control efficacy was only51.63%-72.13%, can not effectively control southern rice black-streaked dwarf disease.By seed dressing agent, spray to kill Sogatella furcifera Horvath and antiviral agents30%Dufuin、0.5%high sensitive protein、1%mushrooms polysaccharide、8%ningnanmycin in the seeding stage, control efficacy were88.05%、86.83%、86.40%、85.40%, all were as high as85%,therefore,it can effectively control southern rice black-streaked dwarf disease occurrence.Large area demonstration tests showed that:the technology of using60%imidacloprid FS (Youban) dressing+spray8%ningnanmycin in the seedling period+spray25%pymetrozine before transplanting and spray8%ningnanmycin early after transplanting+25%pymetrozine, it can achieve better control efficacy in the investigation of the seeding stage, the incidence of demonstration area only2.30%, and the incidence rate of11.20%farmers from the area.