An introgression line RBPH660, derived from wild rice Oryza rufipogon, showed stable resistance to brown planthopper (BPH). Segregation analysis indicated BPH resistance of RBPH660 was controlled by multiple genes/QTLs. By using the bulked segregant analysis (BSA)-seq method, two genomic regions harboring QTLs resistance to BPH were identified from 1.20 to 16.70 Mb on chromosome 4 and from 10.20 to 12.60 Mb on chromosome 9 in RBPH660, respectively. A major resistance locus, designated as Bph35 accounting for 51.27% of the phenotypic variation with a LOD score of 42.51, was mapped to the candidate region of chromosome 4 between InDel (insertion-deletion) markers PSM16 and R4M13. For fine mapping of Bph35, one simple sequence repeat and three newly developed InDel markers were used to screen the recombinants. Finally, the Bph35 locus was delimited in the region from 6.28 to 6.93 Mb and there were 18 predicted protein-encoding genes with a total of 114 non-synonymous single nucleotide polymorphism (SNP) variant sites between the resistant and susceptible parents. Out of these genes, Os04g0193950, encoding a putative NB-ARC (nucleotide- binding adaptor shared by APAF-1, R proteins and CED-4) and LRR (leucine-rich repeat) domain protein with nine non-synonymous SNP substitutions in its coding sequence regions, might be the candidate gene for Bph35. These findings would facilitate the map-based cloning of the Bph35 gene and development of resistant varieties against BPH in rice.

源自野生稻米红麦的渗入系RBPH660表现出对褐飞虱（BPH）的稳定抗性。分离分析表明RBPH660的BPH抗性由多个基因/ QTL控制。通过使用批量隔离分析（BSA）-seq方法，分别在RBPH660的4号染色体上从1.20至16.70 Mb和在9号染色体的10.20至12.60 Mb鉴定了两个具有BTL QTL抗性的基因组区域。一个主要的抗性基因座，被指定为Bph35，占表型变异的51.27％，LOD得分为42.51，被定位到InDel（插入-缺失）标记PSM16和R4M13之间的4号染色体候选区域。用于Bph35的精细映射，使用一个简单的序列重复序列和三个新开发的InDel标记物筛选重组子。最后，Bph35基因座在6.28至6.93 Mb范围内被分隔，并且在抗性和易感亲本之间共有18个预测的蛋白质编码基因，共有114个非同义单核苷酸多态性（SNP）变异位点。在这些基因中，Os04g0193950编码一个假定的NB-ARC（APAF-1，R蛋白和CED-4共有的核苷酸结合衔接子）和LRR（富含亮氨酸的重复序列）结构域蛋白，在其9个非同义SNP取代中编码序列区域，可能是Bph35的候选基因。这些发现将有助于Bph35的基于图的克隆 水稻BPH抗性基因的遗传与开发