Abstract: The annual variation dynamics of brown planthopper (BPH) Nilaparvata lugens (Stal) biotypes was monitored by seedling bulk test, nymph survival rate test in tiUerlng stage and systematic observation in the field from 1979 to 1994. The suitable rice cultivars and resources against the current dominant population and developmental tendency of BPH biotypes were recommended. The results indicated the damage scale of BPH population in Guangzhou on the cultivar IR26 with resistant gene Bphl became higher and higher andreached the level of biotype 2 since 1992. Furthermore, the BPH biotype 2 had become the dominant population in Guangdong Province according to the tests with the population examples collected from 7 ecological localities and the verifying test from 1992 to 1994. The resistance to BPH of IR56 and IR50404 from IRRI as their resistant parent lines PTB33 and Babawee was high and stable according to the resistant tests for years. They have been recommended as the suitable and excellent resistant resources to BPH for further breeding.Twenty-three cultivars including Jing-Xian 89 resistant to the BPH biotype 1 and 2 can beused to take place of the cultivars with resistant gene Bphl in time.

Key words: Nilaparvata lugens (Still), biotype, resistant rice cultivar