Quantitative trait loci for seeding root traits and the relationships between root and agronomic traits in common wheat

A completely developed and vigorous root system can provide a stable platform for aboveground plant organs. To identify loci controlling root traits that could be used in wheat (Triticum aestivum L.) breeding, 199 recombinant inbred lines were used to measure and analyze eight root traits. A total of 18 quantitative trait loci (QTL) located on chromosomes 1A, 2A, 2B, 2D, 4B, 4D, 6A, 7A, and 7B were identified. The phenotypic variation explained by these 18 QTL ranged from 3.27% to 11.75%, and the logarithm of odds scores ranged from 2.50 to 6.58. A comparison of physical intervals indicated several new QTL for root traits were identified. In addition, significant correlations between root and agronomic traits were detected and discussed. The results presented in this study, along with those of previous reports, suggest that chromosomes 2 and 7 likely play important roles in the growth and development of wheat roots. Keywords: Triticum aestivum L., recombinant inbred lines, root traits, quantitative trait loci, correlation. Un systeme racinaire bien developpe et vigoureux peut servir d'assise stable aux organes aeriens de la plante. Afin d'identifier des locus contr[delta]lant des caracteres racinaires utiles en amelioration genetique chez le ble (Triticum aestivum L.), 199 lignees recombinantes fixees ont ete employees pour mesurer et analyser huit caracteres racinaires. Au total, 18 QTL, situes sur les chromosomes 1A, 2A, 2B, 2D, 4B, 4D, 6A, 7A et 7B, ont ete identifies. La variation phenotypique expliquee par ces QTL variait entre 3,27 et 11,75%, et les scores LOD variaient entre 2,50 et 6,58. Une comparaison des intervalles physiques a suggere que plusieurs QTL inedits pour des caracteres racinaires ont ete identifies. De plus, des correlations significatives entre des caracteres racinaires et agronomiques ont ete detectees et sont discutees. Les resultats presentes dans cette etude, avec ceux rapportes anterieurement, suggerent que les chromosomes 2 et 7 jouent des roles importants dans la croissance et le developpement des racines chez le ble. [Traduit par la Redaction] Mots-cles: Triticum aestivum L., lignees recombinantes fixees, caracteres racinaires, locus de caracteres quantitatifs, correlation.
Introduction Common wheat (Triticum aestivum L.) is an important food crop planted worldwide (Ray et al. 2013). The development of high-yielding wheat varieties with good quality is essential in wheat [...]