Differential Responses of Rathu Heenati Accessions Available in Sri Lanka for Brown Planthopper [Nilaparvata Lugens (Stål)] Resistance

Brown Planthopper, BPH [Nilaparvata lugens (Stål)] is one of the most devastating insect pests reported in rice, which accounts for considerable yield losses in paddy throughout the world. The Sri Lankan traditional rice cultivar Rathu Heenati is known to carry a strong BPH resistance and it is used as a donor parent in rice breeding programmes of many countries. Therefore, this study was carried out to determine the BPH resistance in Rathu Heenati accessions conserved at PGRC using phenotypic and molecular characterization. Cultivar screening was done using Standard Seed box Screening Test (SSST), different morphological characters and gene specific molecular markers at the Rice Research and Development Institute, Batalagoda during 2021/2022 Maha season. Morphological analysis showed that there is high diversity among the tested accessions. Phenotypic screening revealed that accessions 005579 and 004992 showed high resistance, and the accession 003390 showed moderate resistance to BPH. Molecular marker SSR and STS studies showed that the accessions 005579 and 004992 contain Bph2, Bph3, Bph10 and Bph13 resistant genes while 005486, 003888, 002080 identified as susceptible accessions containing different combinations of Bph2, Bph3 and Bph13 genes except Bph10. These information can be utilized for efficient introgression of resistant genes, Bph2, Bph3, Bph10 and Bph13 into elite rice cultivars using marker-assisted selection to generate long lasting and a durable BPH resistance in rice.