Screening of Brown Planthopper (Nilaparvata lugens (St˚al)) Resistance in Rathu Heenati Accessions Available in Sri Lanka

Abstract

Brown Planthopper, BPH (Nilaparvata lugens St˚al) is one of the most devastating insect pests reported on the rice crop worldwide. The traditional Sri Lankan rice variety Rathu Heenati has been found to have strong BPH resistance and is widely used as a BPHresistant donor in rice breeding programs in several countries. The current study was conducted to identify BPH resistance in Rathu Heenati accessions available in Sri Lanka through phenotypic and molecular characterization at Rice Research and Development Institute, Batalagoda during the 2021/22 Maha season. Phenotypic characterization for BPH resistance was performed using the standard seedbox screening technique (SSST). Rathu Heenati ’s accessions; 2080, 3888, 4992, 5579, 5486 and 3390 were tested for BPH resistance with BPH resistant var. Ptb33 and susceptible var. Bg380. The molecular markers; RM 589, RM 463, RG457 and AJ096 associated with the BPH resistance genes BPH3, BPH2, BPH10, and BPH13 were used. The results revealed that Rathu Heenati accessions 4992 and 5579 are moderately resistant to BPH. Accession 3390 is moderately resistant/ susceptible to BPH while accessions 2080, 3888, and 5486 are highly susceptible to BPH. The molecular analyzes showed the presence of resistance genes BPH3, BPH2, BPH10, and BPH13 in accessions 4992 and 5579; BPH2 and BPH3 in accession 3390. Therefore, these resistant genes might play an important role in determining some resistance of Rathu Heenati accessions to BPH. Hence Rathu Heenati accessions, especially 4992 and 5579, may be used effectively to develop BPH resistant varieties in rice breeding programs.