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Black pericarp sorghum has notable value due to the biosynthesis of 3-deoxyanthocyanidins (3-DOAs), a rare class of bioactive polyphenols valued as antioxidant food additives and as bioactive compounds with cytotoxicity to human cancer cells. A metabolic and transcriptomic study was conducted to ascertain the cellular events leading to the activation of 3-DOA biosynthesis in black sorghum pericarp. Prolonged exposure of pericarp during grain maturation to high-fluence ultraviolet (UV) light resulted in elevated levels of reactive oxygen species (ROS) and the activation of 3-DOA biosynthesis in pericarp tissues. In conjunction with 3-DOA biosynthesis was the transcriptional activation of specific family members of early and late flavonoid biosynthesis pathway genes as well as the downstream activation of defense-related pathways. Promoter analysis of genes highly correlated with 3-DOA biosynthesis in black pericarp were enriched in MYB and HHO5/ARR-B motifs. Light microscopy studies of black pericarp tissues suggest that 3-DOAs are predominantly localized in the epicarp and are associated with the cell wall. A working model of UV-induced 3-DOA biosynthesis in black pericarp is proposed that shares features of plant immunity associated with pathogen attack or mechanical wounding. The present model depicts ROS accumulation, the transcriptional activation of receptor kinases and transcription factors (TFs) including NAC, WRKY, bHLH, AP2, and C2H2 Zinc finger domain. This study identified key biosynthetic and regulatory genes of 3-DOA accumulation in black pericarp and provided a deeper understanding of the gene networks and cellular events controlling this tissueand genotype-specific trait. [ABSTRACT FROM AUTHOR]

The USDA‐ARS and North Dakota State University Agricultural Experiment Station jointly released the Fusarium head blight (FHB)‐resistant spring wheat (Triticum aestivum L.) germplasm WGC002 (Reg. no. GP‐1089, PI 702949) in May 2023. WGC002 is a wheat‐Thinopyrum elongatum 7B‐7E translocation line, designated 7BS·7BL‐7EL, with the wheat chromosome 7BL terminal region replaced by the homoeologous counterpart of the Th. elongatum chromosome 7EL that contains the novel FHB resistance gene Fhb7The2. WGC002 was developed from the Chinese Spring (CS) wheat‐Th. elongatum disomic substitution line DS 7E(7B) using our genomics‐enabled chromosome engineering pipeline. The pedigree of WGC002 is DS 7E(7B)/2*CS ph1b mutant//DS 7E(7B). WGC002 has consistently exhibited resistance to FHB in inoculations of greenhouse grown plants. WGC002 does not contain the yellow flour pigment gene in the Fhb7The2 haplotype present on the terminal 7EL segment of the 7BS·7BL‐7EL translocation and has not exhibited any obvious linkage drag on the 7EL segment. Therefore, WGC002 is ready for immediate use in wheat breeding. One sequence‐tagged site (STS) and two polymerase chain reaction allelic competitive extension markers were developed specifically for Fhb7The2 and validated in different wheat genotypes. They are highly diagnostic for Fhb7The2 and extremely useful in marker‐assisted introgression of Fhb7The2 in wheat breeding. In summary, WGC002 is a new wild grass‐derived FHB‐resistant spring wheat germplasm with diagnostic DNA markers available to conduct marker‐assisted selection of Fhb7The2, that will enhance and diversify FHB resistance of wheat. Core Ideas: We developed an FHB‐resistant wheat germplasm, WGC002, which contains the wild grass‐derived resistance gene Fhb7The2.Fhb7The2 was incorporated into wheat through a 7B‐7E translocation by chromosome engineering. The chromosome 7E segment containing Fhb7The2 does not carry the gene for yellow flour pigment in WGC002.We developed the STS and PACE markers specific for Fhb7The2. [ABSTRACT FROM AUTHOR]

Hard red spring wheat (HRSW; Triticum aestivum L). production in South Dakota has decreased by nearly 50% over a recent 10‐year timespan due to grower preferences for producing corn (Zea mays L.) and soybean [Glycine max (L.) Merr.]. End‐users of HRSW are concerned with grain protein concentration (GPC). Among growers that still produce HRSW, cultivar selection decisions are heavily based on grain yield potential, and they become most concerned with GPC only when it is low enough to result in sales price discounts. It is important that HRSW breeding programs release new cultivars that balance the needs of both end‐users and growers. The objective of this research was to release a HRSW cultivar possessing both high grain yield potential and GPC for South Dakota and regional producers. 'Ascend‐SD' (Reg. no. CV‐1204, PI 700966) was developed by the SDSU‐HRSW breeding program and released by the South Dakota Agricultural Experiment Station to certified seed producers in early 2022. The cross MN10261‐1/SD4389 was completed during fall 2013, and the resulting population was advanced via an early‐generation bulk‐testing program, where F4:7 seed was included in the 2018 preliminary yield trial and designated as SD4873. Prior to release, SD4873 also was tested in the advanced yield trial from 2019 through 2021 as well as crop performance testing trials in 2020 and 2021. Ascend‐SD was released for its competitive combination of high grain yield potential and GPC. Core Ideas: Ascend‐SD is a new hard red spring wheat cultivar adapted to the upper Great Plains.Agronomic performance of Ascend‐SD is very competitive.Ascend‐SD has good resistance to FHB and BLS. [ABSTRACT FROM AUTHOR]

Background and objectives: Little data have been reported on protein molecular weight distribution (MWD) for waxy (amylose‐free) wheat (Triticum aestivum L.) despite their importance in quality. This research aimed to investigate variations of protein MWD parameters and their associations with gluten strength in winter waxy wheat. Findings: Winter waxy wheat genotypes varied significantly (p < 0.001) for most protein MWD parameters including SDS‐extractable polymeric protein (EPP) and unextractable polymeric protein (UPP) fractions, which are major components of gluten proteins. Allelic variation of HMW glutenin subunits had significant influence on variations of EPP and UPP in waxy genotypes. Negative correlations for EPP and positive correlations for UPP were observed with mixograph peak time and gluten index for wheat genotypes. In particular, highly significant (p < 0.001) correlations were observed between mixograph peak time and the proportion of EPP in total protein for waxy genotypes. Conclusions: Winter waxy wheat genotypes showed significant variations for EPP and UPP parameters, which were associated with variation of gluten strength. Significance and novelty: This research identified variation of protein MWD parameters and their associations with gluten strength. The information should be valuable in segregating winter waxy wheat genotypes that have favorable gluten quality as well as unique waxy starch. [ABSTRACT FROM AUTHOR]

End-use and processing traits in wheat (Triticum aestivum L.) are crucial for varietal development but are often evaluated only in the advanced stages of the breeding program due to the amount of grain needed and the labor-intensive phenotyping assays. Advances in genomic resources have provided new tools to address the selection for these complex traits earlier in the breeding process. We used association mapping to identify key variants underlying various end-use quality traits and evaluate the usefulness of genomic prediction for these traits in hard red spring wheat from the Northern United States. A panel of 383 advanced breeding lines and cultivars representing the diversity of the University of Minnesota wheat breeding program was genotyped using the Illumina 90K single nucleotide polymorphism array and evaluated in multilocation trials using standard assessments of end-use quality. Sixty-three associations for grain or flour characteristics, mixograph, farinograph, and baking traits were identified. The majority of these associations were mapped in the vicinity of glutenin/gliadin or other known loci. In addition, a putative novel multi-trait association was identified on chromosome 6AL, and candidate gene analysis revealed eight genes of interest. Further, genomic prediction had a high predictive ability (PA) for mixograph and farinograph traits, with PA up to 0.62 and 0.50 in cross-validation and forward prediction, respectively. The deployment of 46 markers from GWAS to predict dough-rheology traits yielded low to moderate PA for various traits. The results of this study suggest that genomic prediction for end-use traits in early generations can be effective for mixograph and farinograph assays but not baking assays., (© 2024 The Author(s). The Plant Genome published by Wiley Periodicals LLC on behalf of Crop Science Society of America.)

Sorghum contains a wide array of phytochemicals and their levels are affected by the genotype. Phytochemicals identified in sorghum include phenolic acids, flavonoids, condensed tannins, polycosanols, phytosterols, stilbenes, and phenolamides. Most of these phytochemicals are concentrated in the bran fraction and have been shown to have several potential health benefits, which include antidiabetic, cholesterol-lowering, anti-inflammatory, and anticancer properties. This chapter gives an overview of sorghum genetics relevant to phytochemicals, phytochemicals identified in sorghum grain, and their potential health benefits.

Sorghum (Sorghum bicolor (L.) Moench) contains a wide variety of phenolic compounds and their levels and types depend on the genotype. Sorghums with a pigmented testa contain condensed tannins, which are concentrated in the pigmented testa. In this chapter, three methods of tannin analysis are described: (1) Chlorox bleach test; (2) modified vanillin-HCl assay; and (3) normal-phase high-performance liquid chromatography (NP-HPLC) with fluorescence detection. The Chlorox bleach test is a rapid and inexpensive method that identifies non-tannin and tannin sorghums. The modified vanillin-HCl assay is a colorimetric assay that provides relative tannin values among sorghum samples. The normal-phase HPLC with fluorescence detection separates and quantifies condensed tannins according to their degree of polymerization and confirms the presence or absence of tannins.