水稻单季晚粳播期与灰飞虱虫口密度及条纹叶枯病的关系研究

The relationship between the seedling date and population densities of small brown planthopper and incidence of rice stripe leaf blight in single japonica rice

单季晚粳秧苗期避开灰飞虱迁移高峰期,将会减轻条纹叶枯病发生程度,是一项有效的"绿色防控"技术措施。采用分期播种的方法,研究了单季晚粳播种期对灰飞虱虫口密度、水稻条纹叶枯病发病率影响。结果表明,单季晚粳播种期对灰飞虱虫口密度、水稻条纹叶枯病发病率影响明显,随着播种期从5月中、下旬推迟到6月上、中旬,田间灰飞虱虫口密度明显下降,水稻条纹叶枯病始病期、发病高峰期明显推迟,发病高峰次数减少,发病率显著降低,水稻有效穗数增加、结实率提高,增产效果明显。结合考虑第1代灰飞虱成虫迁移高峰期和水稻安全齐穗期,建议在江淮南部的水稻条纹叶枯病重发区,单季晚粳播种期推迟到6月9～14日。

It will be an effective ＂green prevention＂ measure of reducing the occurrence degree of rice stripe leaf blight by keeping away the seedling stage of the single japonica rice from infection peak period of small brown planthopper. The effects of the seedling date of the single japonica rice on population densities of small brown planthopper and the incidence of rice stripe leaf blight were studied at different sowing dates. The results are as follows. With the delay of seedling time from mid-May or late May to early-June or mid-June, the popula- tion densities of small brown planthopper declined obviously, and the beginning and peak period of rice stripe leaf blight disease was significantly delayed; the number of peak incidence was reduced; the incidence was decreased significantly, and the rice panicles and yield increased. Given the migration peak of the first generation of small brown planthopper adult and rice full panicle stage, the seedling date of single japonica rice should be postponed until June 9-14 in serious area of rice stripe leaf blight disease oecured in southern Jianghuai.