Association mapping for root system architecture traits under two nitrogen conditions in germplasm enhancement of maize doubled haploid lines  

作　　者：Langlang Ma Chunyan Qing Ursula Frei Yaou Shen Thomas Lübberstedt 

机构地区：[1]Department of Agronomy,Iowa State University,Ames 50010,USA [2]Key Laboratory of Biology and Genetic Improvement of Maize in Southwest Region,Maize Research Institute,Sichuan Agricultural University,Chengdu 611130,China

出　　处：《The Crop Journal》2020年第2期213-226,共14页作物学报（英文版）

基　　金：China Scholarship Council(CSC)for Langlang Ma’s funding;USDA’s National Institute of Food and Agriculture(IOW04314,IOW01018);Hatch Multistate Project NC-007;the R.F.Baker Center for Plant Breeding at Iowa State University,for supporting this work.

摘　　要：Root system architecture(RSA)contributes to nitrogen(N)uptake and utilization in maize.In this study,a germplasm enhancement of maize double haploid population of 226 lines genotyped with 61,634 SNPs was used to investigate the genetic basis of RSA under two N levels using a genome-wide association study(GWAS).GLM+PCA,FarmCPU,and MLM models were utilized to balance false positives and false negatives.In total,33 and 51 significant SNP-trait associations were detected under high and low N conditions,respectively.Under high N,SNP S9_2483543 was detected by all models.Linkage disequilibrium(LD)regions of some SNPs overlapped with the intervals of QTL for RSA and N response that were detected in previous studies.In particular,several known genes,Rtcs,Rtcl,Rtcl,and Ms44,were located in the LD regions of S1_9992325,S9_151726472,S9_154381179,and S4_197073985,respectively.Among the candidate genes identified by this study,GRMZM2G139811,GRMZM2G314898,GRMZM2G054050,GRMZM2G173682,GRMZM2G470914,GRMZM2G462325,GRMZM2G416184,and GRMZM2G064302 were involved in seedling,seed,and root system development or N metabolism in Arabidopsis or rice.The markers identified in this study can be used for marker-assisted selection of RSA traits to improve nitrogen use efficiency in maize breeding,and the candidate genes will contribute to further understanding of the genetic basis of RSA under diverse N conditions.

关 键 词：GERMPLASM BREEDING SEEDLING 

分 类 号：S513[农业科学—作物学]