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.

Identification of new QTLs for seed mineral, cysteine, and methionine concentrations in soybean [Glycine max (L.) Merr.]

“…Seed Met concentration had a significant positive association with total N in two populations. However, seed Cys was not correlated with total N, supporting a previous study (Panthee et al 2006a). A striking negative association of N:S ratio with most of the macroand micronutrients across populations suggests that N:S ratio is an indicator of concentrations of several minerals in soybean seeds.…”

“…It is logical that the genomic regions that affect glycinin will affect seed Cys + Met concentrations. Two QTLs that affected Cys also affected Cys + Met concentration, possibly because Cys is an intermediate product in Met biosynthesis (Panthee et al 2006a). …”

“…Studies on understanding genes and processes to improve seed nutritional composition by identifying quantitative trait loci (QTLs) were limited to a few minerals or nutrients in soybean (Jegadeesan et al 2010;King et al 2013;Panthee et al 2006a;Zhang et al 2009). Four QTLs for seed Ca concentration were detected, one of which accounted for up to 16.3% of variation (Zhang et al 2009).…”

Integration of Major QTLs of Important Agronomic Traits in Soybean

“…For the QTL information of amino acid content, only 3 researches involved (Panthee, 2006b(Panthee, , 2006cBingchang Zhuang, 2000). In total, 111 QTLs were mapped with RIL population.…”

Soybean Seed Amino Acid Content QTL Detected Using the Uni - versal Soy Linkage Panel 1.0 with 1,536 SNPs

“…The only QTL for amino acids on SoyBase are from Panthee et al (2006a) and(2006b) (Grant et al, 2010; http://soybase.org/). In both studies 101 F 6 -derieved recombinant inbred lines (RILs) developed from a cross of 'N87-984-16' x 'TN93-99' were screened using a total of 94 polymorphic simple sequence repeat (SSR) molecular genetic markers.…”