| Abstract: | An interspecific hybrid line pf9279 was obtained by protoplast fusion between 02428(japonica, with a wide compatibility gene) and CNW240 (O. officinalis, from Malaysia) at CNRRI in 1992. Possible introgression of planthopper resistance from O.officinalis into pf9279 was investigated by field and laboratory experiments during 1998-1999 at CNRRI. Thirty-day-old seedlings of pf9279 and other rice varieties were individually transplanted with a spacing of 18× 24 cm in each plot (ca 7× 20 m) on Jun 15, 1999. Population trends of brown planthopper(BPH), Nilaparvata lugens, and whitebacked planthopper(WBPH),Sogatella furcifera were examined weekly by visual counting of adult females on 50-100 hills for each variety. |
