中国水稻害虫发生与防治研究进展

<正> 水稻害虫对我国水稻的高产、稳产影响极大,一般年份损失约10％,大发生年达20％。据中国科学院动物研究所报道,全国稻区已知的稻虫种类有250多种,其中严重危害的有二化螟、三化螟、稻纵卷叶螟、褐飞虱、白背飞虱和黑尾叶蝉等6种;某些年份或局部地区危害较重的有大螟、稻苞虫、稻蓟马等31种;其余种类危害较轻或偶而见到。我国稻虫种类虽多,但其中以

STATUS OF RICE INSECTS CONTROL IN CHINA

Rice insects are major constrains to rice production. More than250 insect species that can be found in rice field are identified in China. Ofthese, the striped stem borer (Chilo suppressalis), the yellow stem borer (Trypo-ryza incertulas), the rice leaf folder (Cnaphalocrocis medinalis), the brown pla-nthopper (Nilaparvata lugens), the whitebacked planthopper (Sogatella furcifera)and the green leafhopper (Nephotettix cincticeps) are most important and can ca-use significant economic damage in most rice growing areas. And 31 species ca-use yield losses at given years or in partial regions of this country and other sp-ecies only make a little yield losses occasionally or no yield losses generally.The outbreak regularity, the epidemic forecast and the integrated managementof major rice insect species have been studied for different cultivated forms andfruitful results have been made since the People's Republic of China stood. up.The forecasting stations at a county level and the national forecasting units wereestablished in all provinces or autonomous regious of China in past 40 years. Fo-recast technology developed for the stem borer, the planthoppers and the leaf fo-lder, etc. has already played an important role in managing these pests.Since 1970's, a good advance has been made in studies and in utilization ofthe variety resistant. It has been reported that a total of 56186 rice cultivarsor lines from both domestic and oversea have been evaluated for insect resistanceby five rice growing provinces, Jiangsu, Hunan, Zhejiang, Guangdong and Sichuan. About 6 030.accessions were identified with mediate or high resistance. Some ofimproved rice lines with genetic resistance have been widely used as commercialcrops.A network of screening pesticides was established in the 1980's and hundredsof new insecticides were evaluated for different rice insect species. Some of higheffective, low toxic and little biocidal insecticides such as Applaud, Troben, Mi-pcin and Shachon shuang have been screened for practical use. The network hasplayed an important role in guiding farmers to spray insecticides scientifically.Methods of pesticides application were also improved in the network.A national IPM program was conducted in five growing regions in recent ye-ars. The IPM technology strategy has already been developed. Spreading resista-nt varietes is one of the main tactics and adequate fertilization, scientifically ir-rigation, improved methods of insecticides application and protection of naturalenemies were emphasized in the IPM strategy. It was proved that the infectedplants have the potentiality of compensating themselves by their internal regulati-On, therefore, the economical threshold for the rice leaf folder, the striped stemborer and the rice thrip could be widened to 2--5 times that of the conventionalcontrol index. Today, IPM technology has been implemented at the farmer levelin this country.