Identification and fine mapping of qWBPH11 conferring resistance to whitebacked planthopper ( Sogatella furcifera Horvath) in rice ( Oryza sativa L.)

The whitebacked planthopper (WBPH), Sogatella furcifera Horvath, is one of the most destructive pests in rice ( Oryza sativa L.) production. Host-plant resistance has been considered as an efficient and eco-friendly strategy to reduce yield losses caused by WBPH. In this study, we found that an indica rice cultivar IR54751-2-44-15-24-2 (IR54751) displayed high resistance to WBPH at both seedling and tillering stages. The resistance of IR54751 was mainly contributed by antixenosis and tolerance rather than antibiosis. An F 2 population derived from a cross between IR54751 and a susceptible japonica cultivar 02428 was constructed to detect the quantitative trait loci (QTLs) conferring the resistance to WBPH. In total, four QTLs including qWBPH3.1 , qWBPH3.2 , qWBPH11 , and qWBPH12 were identified and distributed on three different chromosomes. The four QTLs had LOD scores of 3.8, 8.2, 5.8, and 3.9, accounting for 8.2, 21.5, 13.9, and 10.4% of the phenotypic variation, respectively. Except for qWBPH3.1 , the resistance alleles of the other three QTLs were all from IR54751. Further, a secondary population harboring only single qWBPH11 locus was developed from the F 2 population by marker-assisted selection. Finally, qWBPH11 was delimited in a 450-kb region between markers DJ53973 and SNP56. The identification of WBPH resistance QTLs and the fine mapping of qWBPH11 will be helpful for cloning resistance genes and breeding resistant rice cultivars.