RESUMO
Rhus aromatica inhabits humid oak and oakpine forests in the State of Michoacán (Mexico). The fruit of R. aromatica is edible and is traditionally used in the preparation of soft drinks, ice pops, ice creams and 'atole'. The objective of the present investigation was to carry out a physical and chemical characterization and analysis of the antioxidant capacity of fruit. For the physical characterization, the equatorial and longitudinal diameter, weight and percentage of pulp were determined. In the chemical characterization, a proximal analysis was carried out, quantification of polyphenols and flavonoids was performed, and the antioxidant capacity was determined. The results showed that the fruit had a longitudinal diameter of 6.58 ± 1.02 mm, an equatorial diameter of 7.17 ± 0.66, a weight of 55.22 ± 5.47 mg, and a 40 % pulp proportion. The chemical characterization analysis indicated 8.7 % moisture, 30.6 % lipids, 8.7 % proteins, 29.4 % total sugars, 3.8 % ashes and 18.7 % crude fibre, 3.1 °Brix, pH 3.1, 1.92 % acidity total and a caloric intake of 4.27 kcal/g. The polyphenol content was higher in 60 % ethanol extracts with 88.6 ± 50.89 mg EAG/g; for flavonoids from extracts with 100 % acetone, it was 26.52 ± 0.65 mg EQ/g, and the total carotenoid content was 46.37 mg/100 g. The total antioxidant activity was higher in extracts with 80 % acetone, with 87.17 % inhibition of the DPPH radical and 90 % inhibition of ABTS without showing a significant difference with the different solvents used. The lowest IC50 values were presented in 100 % ethanol and 60 % methanol extracts for the DPPH radical and for the ABTS radical were the 80 % ethanol and 60 % methanol extracts. The lipid, protein, carotenoid, and polyphenol contents and antioxidant capacity of the fruit of R. aromatica were as high as those of other fruits consumed in the human diet.
RESUMO
Yellow rust (YR) or stripe rust, caused by Puccinia striformis f. sp tritici Eriks (Pst), is a major challenge to resistance breeding in wheat. A genome wide association study (GWAS) was performed using 22,415 single nucleotide polymorphism (SNP) markers and 591 haplotypes to identify genomic regions associated with resistance to YR in a subset panel of 419 pre-breeding lines (PBLs) developed at International Center for Maize and Wheat Improvement (CIMMYT). The 419 PBLs were derived from an initial set of 984 PBLs generated by a three-way crossing scheme (exotic/elite1//elite2) among 25 best elites and 244 exotics (synthetics, landraces) from CIMMYT's germplasm bank. For the study, 419 PBLs were characterized with 22,415 high-quality DArTseq-SNPs and phenotyped for severity of YR disease at five locations in Mexico. A population structure was evident in the panel with three distinct subpopulations, and a genome-wide linkage disequilibrium (LD) decay of 2.5 cM was obtained. Across all five locations, 14 SNPs and 7 haplotype blocks were significantly (P < 0.001) associated with the disease severity explaining 6.0 to 14.1% and 7.9 to 19.9% of variation, respectively. Based on average LD decay of 2.5 cM, identified 14 SNP-trait associations were delimited to seven quantitative trait loci in total. Seven SNPs were part of the two haplotype blocks on chromosome 2A identified in haplotypes-based GWAS. In silico analysis of the identified SNPs showed hits with interesting candidate genes, which are related to pathogenic process or known to regulate induction of genes related to pathogenesis such as those coding for glunolactone oxidase, quinate O-hydroxycinnamoyl transferase, or two-component histidine kinase. The two-component histidine kinase, for example, acts as a sensor in the perception of phytohormones ethylene and cytokinin. Ethylene plays a very important role in regulation of multiple metabolic processes of plants, including induction of defense mechanisms mediated by jasmonate. The SNPs linked to the promising genes identified in the study can be used for marker-assisted selection.