Brown planthopper (BPH) is a phloem sap-sucking insect pest of rice, which causes severe yield loss annually. Gayabyeo, a Tongil type rice variety, is known to have broad spectrum resistance to BPH. Before, it was estimated that Gayabyeo has at least two BPH resistance genes. We started a research for mapping resistance genes of Gayabyeo. We did a cross between Taebaekbyeo, a BPH susceptible Tongil type rice variety, and Gayabyeo, We grew F1 plants in winter season of 2014-2015, and planted F2 population in this year. About 100 DNA markers (SSR and InDel markers) showing polymorphism between Gayabyeo and Tabaekbyeo were selected. In addition, we are going to do resequencing Gayabyeo and Taebaekbyeo using Illumina Hiseq2000 to find much more DNA polymorphisms between the two varieties and develop new markers for mapping. The BPH response data will be acquired using F3 plants from the cross between Gayabyeo and Taebaekbyeo next year. In a while, crosses between Gayabyeo and high quality japonica rice varieties are being carried out to introduce BPH resistance genes of Gayabyeo into japonica high quality rice varieties. We expect to develop new DNA markers for BPH resistance genes of Gayabyeo through mapping and produce several japonica high quality rice lines harboring those genes at the end of this project.

• Hyeonso Ji(Department of Agricultural Biotechnology, National Academy of Agricultural Science) Corresponding Author
• Eokkeun Ahn(Department of Central Area, National Institute of Crop Science)
• Seung-Bum Lee(Department of Agricultural Biotechnology, National Academy of Agricultural Science)
• Seok-Chul Suh(Department of Agricultural Biotechnology, National Academy of Agricultural Science)