西北早粳稻核心种质资源粒形GWAS分析及基因候选OA

[Objective]The study aims to identify candidate genes associated with rice grain shape traits through genome-wide association study(GWAS),with the goal of providing effective genetic improvement targets for enhancing yield and improving quality.[Method]139 germplasm resource materials were planted in Ningxia and Hainan in 2023 and 2024,and the grain length(GL),grain width(GW),grain thickness(GT)and length-to-width ratio(LWR)of each germplasm were determined after harvest.255 501 high-quality single nucleotide polymorphism SNPs were used for marking,and GWAS analysis was performed in combination with general linear model GLM.The range of candidate genes was determined by linkage disequilibrium LD attenuation distance,and the candidate genes related to grain shape were screened in combination with functional annotation and haplotype analysis.[Result]Forty significantly related SNP loci were detected under the conditions of grain length,grain width and grain thickness threshold-log10(p)≥5.41 and aspect ratio threshold-log10(p)≥8.99,and five candidate genes were identified near these SNP loci.Among the candidate genes,LOC_Os06g43920 was the B-type response regula-tor gene ORR5,and the others were all expressed proteins.[Conclusion]LOC_Os04g47030,LOC_OS05G10560,LOC_Os05g10625,LOC_Os06g34810 and LOC_Os06g43920 are identified as candidate genes for the regulation of rice grain shape.