Quantitative Trait Loci for Seed Protein and Oil Concentration, and Seed Size in Soybean

Abstract

to increase the concentration of one at the expense of the other. Soybean [Glycine max (L.) Merr.] is an important crop becauseHardiness, brittleness, and gumminess are important of its high oil and protein concentration. However, there is an inverse relationship between seed protein and oil concentration, making it physical properties, which determine the overall quality difficult to improve both traits simultaneously. Molecular breeding of tofu. Protein concentration, particularly glycinin, demay be helpful to facilitate a balanced accumulation of desirable termines these properties in tofu, whereas seed size dealleles. The objective of this study was to identify quantitative trait termines the quality of soy sprouts (Liu, 1997). Small loci (QTL) governing soybean protein, oil and seed size. To achieve seeded soybeans are generally desired for high quality this objective, 101 F 6 -derived recombinant inbred lines (RIL) from soy sprouts and natto production, and combining higher a population developed from a cross of N87-984-16 ϫ TN93-99 were protein with large seed size is desirable for tofu producused. Heritability estimates on an entry mean basis for protein and tion. Genomic regions for seed size along with protein oil concentrations, and seed size were 0.66, 0.54, and 0.71, respectively. and oil QTL could be used in marker-assisted selection A total of 585 simple sequence repeat (SSR) molecular genetic mark-(MAS) for desired soybean types for soy food appliers were screened and 94 were polymorphic in the RIL. Single factor ANOVA was used to identify candidate QTL, which were then con-cations. firmed by composite interval mapping. One novel molecular marker Despite moderately high heritabilities (Burton, 1987), (Satt570) on molecular linkage group (MLG) G associated with a it is difficult to improve seed traits, particularly protein protein QTL was detected. Novel molecular markers (Satt274, Satt420, and oil concentration, simultaneously. MAS might be useand Satt479) located on MLG D1b, O, and O respectively and a ful in achieving specific goals if genomic regions controlpreviously reported marker (Satt317) located on MLG H were associling protein and oil concentration and seed size could be ated with oil QTL in this study. Molecular markers Satt002 (MLG D2) identified to improve selection indices more precisely. and Satt184 (MLG D1a) associated with seed size QTL were verified Several researchers have paved the way toward this whereas Satt147 (MLG D1a) was novel. The individual QTL explained goal (Brummer et al., 1997; Chung et al., 2003; Diers et 20.2, 9.4-15, and 10 to 16.5% of the phenotypic variation for protein al., 1992;Lee et al., 2001; Lee et al., 1996c). Qiu et al. and oil concentrations, and seed size, respectively. Thus, we identified major loci for improving soybean seed quality.

QTL mapping for protein content in soybean cultivated in two tropical environments

“…According to the Soybase (2008), 76 QTL have been identified and reported as related to protein content. However, little consistency has been observed for QTL expressed in different environments or different populations (Brummer et al, 1997;Fasoula et al, 2004;Panthee et al, 2005). In the present study, this fact might be explained by the high genotype vs. environment interaction observed and by the fact that these QTL can be considered environmentally sensitive (Brummer et al, 1997).…”

“…Mapping and QTL detection studies for protein content in seeds have been reported extensively in literature (Chung et al, 2003;Fasoula et al, 2004;Hyten et al, 2004;Panthee et al, 2005). However, many reported QTL have still to be confirmed and their consistency validated (Fasoula et al, 2004).…”

“…However, many reported QTL have still to be confirmed and their consistency validated (Fasoula et al, 2004). According to Panthee et al (2005), the QTL reported with greatest consistency for protein content in soybean is located in the MLG I linkage group, close to the Satt292 microsatellite marker. The same study showed the difficulty for validating previously detected QTL, considering the need to carry out experiments in distinct environments, with different population structures and for different genetic backgrounds.…”

Genome-wide association for mapping QTLs linked to protein and oil contents in soybean

“…Csanádi et al (2001) identified QTLs for oil content on chromosomes 14, 9, and 20. Panthee et al (2005) reported QTLs on chromosomes 2, 10, and 18. The QTL of chromosome 2 was also detected by Zhang et al (2004).…”

Associação de marcadores microssatélites com teores de óleo e proteína em soja

“…Vários marcadores de locos de caracteres quantitativos (QTL) foram relatados para teores de óleo e proteína em soja (Sebolt et al, 2000;Csanádi et al, 2001;Specht et al, 2001;Chung et al, 2003;Chapman et al, 2003;Tajuddin et al, 2003;Fasoula et al, 2004;Hyten et al, 2004;Zhang et al, 2004;Panthee et al, Pesq. agropec.…”