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Key message: One hundred and fifty-five QTL for trace element concentrations in foxtail millet were identified using a genome-wide association study, and a candidate gene associated with Ni–Co–Cr concentrations was detected. Foxtail millet (Setaria italica) is an important regional crop known for its rich mineral nutrient content, which has beneficial effects on human health. We assessed the concentrations of ten trace elements (Ba, Co, Cr, Cu, Fe, Mn, Ni, Pb, Sr, and Zn) in the grain of 408 foxtail millet accessions. Significant differences in the concentrations of five elements (Ba, Co, Ni, Sr, and Zn) were observed between two subpopulations of spring- and summer-sown foxtail millet varieties. Moreover, 84.4% of the element pairs exhibited significant correlations. To identify the genetic factors influencing trace element accumulation, a comprehensive genome-wide association study was conducted, identifying 155 quantitative trait locus (QTL) for the ten trace elements across three different environments. Among them, ten QTL were consistently detected in multiple environments, including qZn2.1, qZn4.4, qCr4.1, qFe6.3, qFe6.5, qCo6.1, qPb7.3, qPb7.5, qBa9.1, and qNi9.1. Thirteen QTL clusters were detected for multiple elements, which partially explained the correlations between elements. Additionally, the different concentrations of five elements between foxtail millet subpopulations were caused by the different frequencies of high-concentration alleles associated with important marker-trait associations. Haplotype analysis identified a candidate gene SETIT_036676mg associated with Ni accumulation, with the GG haplotype significantly increasing Ni–Co–Cr concentrations in foxtail millet. A cleaved amplified polymorphic sequence marker (cNi6676) based on the two haplotypes of SETIT_036676mg was developed and validated. Results of this study provide valuable reference information for the genetic research and improvement of trace element content in foxtail millet. [ABSTRACT FROM AUTHOR]

Eating quality (EQ) of rice is mainly determined by sensory evaluation using tasting, which is affected by the taster's geographic residential area, gender, and age. The sensory evaluation protocol also requires rice samples (usually > 500 g) larger than the amount harvested from the early generations of breeding in many cases, thereby hindering the sensory tasting practices. The characteristics of rice starch have a significant impact on EQ; however, information on starch assisted-selection of EQ is insufficient. In this study, the recombinant inbred lines and backcross recombinant inbred lines constructed by the hybridization of japonica (O. sativa L. ssp. japonica) rice (cv. Toyonishiki) and indica (O. sativa L. ssp. indica) rice (cv. Qishanzhan) were used as test materials to analyze and explore the relationships between the amylose content (AC), rapid visco analyzer (RVA) profile characteristics, and the EQ score obtained from sensory tasting assessment. We provided a feasible solution to use rice starch properties to assist in selection of EQ. The results indicated that AC and RVA profile characteristics including trough viscosity (TV), final viscosity (FV), breakdown (BD), and setback (SB) were closely related to the EQ values. Furthermore, an integrated indicator—i.e., starch properties quality (SPQ)—that represented a more comprehensive characterization of rice starch, was derived based on the EQ evaluation hierarchy and weighted AC, TV, FV, BD, and SB values. The correlation between SPQ and EQ was significant (p < 0.001), and was significantly higher compared with using individual indicators. Moreover, the SPQ method requires less rice samples (i.e., 3 g of milled rice flour) and can be applied to assisted-selection for EQ in early generations of breeding. This study provid esessential technical support for the rapid and accurate identification of the EQ of progeny of indica–japonica hybrids. [ABSTRACT FROM AUTHOR]

Two intraspecific peach breeding populations have been used to conduct a quantitative trait locus (QTL) analysis of fruit quality traits: an F from the cross Bolero (B) x OroA (O) and an F from the cross Contender (C) x Ambra (A). A total of 344 Prunus simple sequence repeats (SSRs) were analyzed in B, O, C, A parents and CxA F hybrid. Eight SSR were mapped for the first time in peach. A multiplex-ready polymerase chain reaction (PCR) protocol has allowed considerable time and cost saving during genotyping steps. Two maps ( B map and O map) were produced for BxO population following the pseudo-test cross strategy and one for CxA. No marker could be mapped on G6 for the B map, on G4 and G8 for the O map and on G5 for the CxA map. Both populations were phenotyped over 2 years for maturity date (MD), fruit weight, external fruit skin overcolor, juice total soluble solids (SSC, Brix degree), juice titrable acidity and juice pH. Data for blooming time and flower type were scored only for BxO in 2007. All traits had a normal distribution, except for MD which was bimodal in BxO and trimodal in CxA, where it was scored as a co-dominant trait. Up to two QTLs per trait were detected in each population, and most of them were located in the same region forming clusters of QTLs, especially on G4. This is likely due to a major pleiotropic effect of MD masking the identification of other QTLs for different traits. [ABSTRACT FROM AUTHOR]

The antinutritional factors found in soybean, lectin (SBL) and Kunitz trypsin inhibitor (SKTI), are usually inactivated by heat treatment. However, residual activity of these factors can be found in several types of soy-derived products. Heat treatment does not completely eliminate these factors, and in addition it may considerably decrease protein solubility. The genetic elimination of these antinutritional factors could be an alternative to the heat treatment. This study aimed to develop soybean lines devoid of SKTI and SBL in their seeds. The population under study was obtained by crossing the normal cv. Monarca with a soybean line lacking SKTI and SBL. Specific DNA primers were designed for the identification of the recessive alleles that condition the absence of SKTI and SBL. F2 seeds presenting the DNA markers that identify the recessive alleles were selected and the corresponding F2 plants were backcrossed with the recurrent parent (‘Monarca’), producing the BC1F1 generation. The F2 generation was analyzed by SDS-PAGE in order to confirm the genotypes of the F2 selected. The segregation tests confirmed that these traits are governed by two genes that segregate independently. [ABSTRACT FROM AUTHOR]