title: Quantitative trait loci controlling sulfur containing amino acids, methionine and cysteine, in soybean seeds.
abstract: Soybean [Glycine max (L.) Merr.] is the single largest source of protein in animal feed. However, a major limitation of soy proteins is their deficiency in sulfur-containing amino acids, methionine (Met) and cysteine (Cys). The objective of this study was to identify quantitative trait loci (QTL) associated with Met and Cys concentration in soybean seed. To achieve this objective, 101 F(6)-derived recombinant inbred lines (RIL) from a population developed from a cross of N87-984-16 x TN93-99 were used. Ground soybean seed samples were analyzed for Met and Cys concentration using a near infrared spectroscopy instrument. Data were analyzed using SAS software and QTL Cartographer. RIL differed (P<0.01) in Met and Cys concentrations, with a range of 5.1-7.3 (g kg(-1) seed dry weight) for Cys and 4.4-8.8 (g kg(-1) seed dry weight) for Met. Heritability estimates on an entry mean basis were 0.14 and 0.57 for Cys and Met, respectively. A total of 94 polymorphic simple sequence repeat molecular genetic markers were screened in the RIL. Single factor ANOVA was used to identify candidate QTL, which were confirmed by composite interval mapping using QTL Cartographer. Four QTL linked to molecular markers Satt235, Satt252, Satt427 and Satt436 distributed on three molecular linkage groups (MLG) D1a, F and G were associated with Cys and three QTL linked to molecular markers Satt252, Satt564 and Satt590 distributed on MLG F, G and M were associated with Met concentration in soybean seed. QTL associated with Met and Cys in soybean seed will provide important information to breeders targeting improvements in the nutritional quality of soybean.
authors.affiliation: Department of Plant Sciences, University of Tennessee, 2431 Joe Johnson Dr, 252 Ellington Plant Sciences Bldg, Knoxville, TN 37996, USA.
authors.forename: D R
authors.initials: DR
authors.lastname: Panthee
authors.forename: V R
authors.initials: VR
authors.lastname: Pantalone
authors.forename: C E
authors.initials: CE
authors.lastname: Sams
authors.forename: A M
authors.initials: AM
authors.lastname: Saxton
authors.forename: D R
authors.initials: DR
authors.lastname: West
authors.forename: J H
authors.initials: JH
authors.lastname: Orf
authors.forename: A S
authors.initials: AS
authors.lastname: Killam
mesh_terms: D000596:Amino Acids / Q000032:analysis / Q000737:chemistry; D000704:Analysis of Variance; D002874:Chromosome Mapping; D032461:Chromosomes, Plant; D003433:Crosses, Genetic; D003545:Cysteine / Q000032:analysis* / Q000737:chemistry; D018744:DNA, Plant; D008040:Genetic Linkage; D005819:Genetic Markers; D014644:Genetic Variation; D008126:Lod Score; D008715:Methionine / Q000032:analysis* / Q000737:chemistry; D018895:Microsatellite Repeats; D011110:Polymorphism, Genetic; D040641:Quantitative Trait Loci; D011995:Recombination, Genetic; D012639:Seeds / Q000737:chemistry / Q000235:genetics*; D013025:Glycine max / Q000235:genetics*; D019265:Spectroscopy, Near-Infrared
chemical_list: D000596:Amino Acids; D018744:DNA, Plant; D005819:Genetic Markers; D008715:Methionine; D003545:Cysteine