565 research outputs found

    Comprehensive phenotypic analysis and quantitative trait locus identification for grain mineral concentration, content, and yield in maize (Zea mays L.)

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    Biofortification by enhanced mineral density in maize grain through genetic improvement is one of the efficient ways to solve global mineral malnutrition, in which one key step is to detect the corresponding Quantitative Trait Loci (QTL). In this work, a maize recombinant inbred population (RIL) was grown to maturity in four field environments with two locations × two years. Phenotypic data of mineral nutrition concentration, content and yield were determined for grain copper (Cu), iron (Fe), manganese (Mn), zinc (Zn), magnesium (Mg), potassium (K) and phosphorus (P). Analysis of variance (ANOVA) showed significant effects of genotype, location and year for all investigated traits. Location showed the highest effect for all mineral yields, and Zn and Cu content and concentration, while year had the strongest impact for Mn, K, and P content and concentration. Heritabilities (h2) of different traits varied with higher h2 (72-85%) for mineral concentration and content and lower (48-63%) for nutrient yields. Correlation coefficient analysis revealed significant positive correlations for grain concentration between several minerals. P had the closest correlations to other elements, while Cu had the lowest. When environments were analyzed individually, a total of 28, 25, and 12 QTL were identified for nutrient concentration, content and yield, respectively. Among these QTL, 8 QTL were consistent within traits across different environments. These stable QTL may be most promising for controlling mineral accumulation in maize grain. Co-localization of QTL for different traits was found for 12 chromosome regions, suggesting that common processes might contribute seed nutrient accumulatio

    Measurement of the top quark forward-backward production asymmetry and the anomalous chromoelectric and chromomagnetic moments in pp collisions at √s = 13 TeV

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    Abstract The parton-level top quark (t) forward-backward asymmetry and the anomalous chromoelectric (d̂ t) and chromomagnetic (Ό̂ t) moments have been measured using LHC pp collisions at a center-of-mass energy of 13 TeV, collected in the CMS detector in a data sample corresponding to an integrated luminosity of 35.9 fb−1. The linearized variable AFB(1) is used to approximate the asymmetry. Candidate t t ÂŻ events decaying to a muon or electron and jets in final states with low and high Lorentz boosts are selected and reconstructed using a fit of the kinematic distributions of the decay products to those expected for t t ÂŻ final states. The values found for the parameters are AFB(1)=0.048−0.087+0.095(stat)−0.029+0.020(syst),Ό̂t=−0.024−0.009+0.013(stat)−0.011+0.016(syst), and a limit is placed on the magnitude of | d̂ t| < 0.03 at 95% confidence level. [Figure not available: see fulltext.

    An embedding technique to determine ττ backgrounds in proton-proton collision data